SNR Climate Corner

May 2013, Lincoln, NE, Climate Summary

noreply@blogger.com (Ken Dewey) — Sun, 02 Jun 2013 15:39:00 +0000

May 2013 Lincoln, NE, Climate Summary

May 2013 was the 7th wettest May on record for Lincoln, NE, with 127 years of data (1887-2013). Temperatures in May were slightly below normal and there were three record events.

Lincoln Top Ten Wettest Mays
Precipitation in inches

Wettest      Amount    Rank

1903          10.72      1
2001          10.16      2
1896          10.11      3
1996          10.09      4
1892           9.55      5
1959           8.91      6
2013           8.44      7 
2007           8.13      8
1984           7.97      9

1951           6.71     10

Here are the summary statistics for May 2013 with a graph below the statistics.

May 2013 Temperature Statistics
Average High Temperature 72.7 F (1.5 degrees BELOW Normal)
Average Low Temperature 50.2 F (0.3 degrees BELOW Normal)
Mean Temperature 61.5 F (0.8 degrees BELOW Normal)
Note: Mean temperature = the average of all the highs and lows
Number of days ABOVE Normal = 15
Number of Days BELOW Normal = 14
Number of Days exactly Normal = 2
Highest temperature 100 F on May 14 (new record high for the date)
Lowest temperature 31 F on May 12 (a new record low for the date)

May 2013 Precipitation Statistics
Total all precipitation 8.44 inches (4.15 inches ABOVE Normal)
Note: All precipitation = rain plus melted snow water equivalent
Total Snowfall 2.7 inches (Normal is zero, i.e. no snow in May)
Heaviest precipitation 3.32 inches on May 27 (a new record for the date)

VERY RARE May 2013 Snowfall
A total of 2.7 inches of snow was officially recorded in Lincoln, NE on May 1-2, 2013.
This was the first measured snowfall in Lincoln since 1967.
LINK: >>>MAY 2013 Snowfall Story Report

These are the only May snowfalls of record in Lincoln:

May 3, 1907: 2.2 inches
May 3-4, 1967: 3.0 inches

May 1-2, 2013: 2.7 inches

LINK>>> May 2013 Lincoln Data Page

LINK>>> May 2013 Photo Gallery

The following graph shows the Lincoln, NE, May 2013 daily high and low temperatures compared to normal daily highs and lows. NOTE: Two maps are located below the graph.

The RED line is the normal high and the BLUE line is the normal low.
The top of each vertical bar is the high for the day and the bottom of each vertical bar is the low for the day.

All data in this graph are from the National Weather Service and HPRCC data archives.

The next two maps show the precipitation departure ffrom normal and temperature departure from normal for the month of May 2013 for the High Plains Regions so that the May 2013 climate of Lincoln, NE can be compared to the surrounding region.

A Very Wet Week in Nebraska and the Great Plains

noreply@blogger.com (Ken Dewey) — Fri, 31 May 2013 14:35:00 +0000

It has been exceptionally wet in Nebraska and in the Great Plains during the past 7 days.

The two maps below show the radar estimated precipitation for the conterminous U.S. as well as for the Nebraska region for the time period May 4 -May 31, 2013.

It is a little difficult to see the Nebraska locations in the second map but look carefully and you will be able to find LNK for Lincoln, LBF for Scottsbluff and VTN for Valentine.

Estimated rainfall totals during this one week time period range from 1-4 inches of rain in Western Nebraska, 4 to 8 inches of rain in Central Nebraska and more than 8 inches of rain in Eastern Nebraska.

Here in Lincoln, NE, we received an official measured total of 5.99 inches during this one-week time period. The total May 2013 measured precipitation for Lincoln (through May 30) is 8.14 inches which is the 7th greatest monthly total for May with 127 years of data (1887-2013). Here is a link to the monthly precipitation records for Lincoln, NE, >>> Top Ten Wettest/Driest Months.

May 29, 2013: Nebraska's "Tornado Drought" Ends

noreply@blogger.com (Ken Dewey) — Thu, 30 May 2013 16:52:00 +0000

The following map shows the storm reports submitted to the Storm Prediction Center in Norman, OK.

There were a total of 23 tornadoes reported to the SPC for May 29, 2013. The term "filtered" means they have attempted to filter out any potential duplicate reports. Duplicate reports occur when the same tornado is seen by multiple observers. For example an observer might report seeing a tornado and they are 4 miles west of the tornado and another observer sees the same tornado but they are 5 miles east of the tornado. The 9 mile distance at first might make it seem like they saw two different tornadoes , yet in fact it was the same tornado. At the end of the year all of the tornado reports are analyzed to make sure that as best as possible any and all duplicate reports are eliminated.

The total of 16 tornadoes in Nebraska may ultimately be lowered by a few but it still remains as the most active day for tornadoes in Nebraska in over a year.

Here are some photos of the York, Nebraska May 29, 2013 tornado:

Here is a listing of the tornado reports for May 29, 2013:
Note all times are UTC (CDST is UTC - 5 hours) so 1956 UTC = 1456 or 2:56 pm CDST,

Time	Location	County	State	Lat	Lon	Comments

1956	3 N CLAY CENTER	CLAY	NE	4057	9805	MULTIPLE REPORTS OF A TORNADO NORTH OF CLAY CENTER. (GID)
2045	6 N SUTTON	CLAY	NE	4069	9786	(GID)
2120	7 W YORK	YORK	NE	4087	9773	ROPE TORNADO BRIEFLY ON GROUND. HAS LIFTED. (GID)
2121	2 N CLAY CENTER	CLAY	NE	4055	9805	TORNADO ON GROUND AT PRESENT TIME. (GID)
2127	4 N CLAY CENTER	CLAY	NE	4058	9805	RAIN WRAPPED TORNADO STILL ON GROUND NEAR HIGHWAY 6 AND ROAD P. (GID)
2133	6 SW STOCKHAM	CLAY	NE	4066	9802	OUT BUILDING REPORTED DESTROYED ALONG WITH TREE DAMAGE NEAR ROAD P AND 318. TORNADO REPORTED ON GROUND APPROACHING STOCKHAM. (GID)
2136	3 NW YORK	YORK	NE	4090	9764	(GID)
2146	1 W COMSTOCK	CUSTER	NE	4156	9926	TORNADO ON THE GROUND ONE HALF MILE WEST OF COMSTOCK. (LBF)
2151	3 S YORK	YORK	NE	4083	9760	BRIEF TOUCHDOWN AND SINCE LIFTED. (GID)
2157	1 SE YORK	YORK	NE	4086	9758	DAMAGE REPORTED TO A FARMSTEAD LOCATED NEAR THE INTERSECTION OF ROAD 12 AND ROAD N. MINOR DAMAGE TO HOME BUT SIGNIFICANT DAMAGE TO OUTBUILDINGS. (GID)
2200	2 SSE YORK	YORK	NE	4084	9758	REPORT OF RAIN WRAPPED TORNADO DIFFICULT TO SEE WITH OCASSIONAL DEBRIS PUFFS. (GID)
2200	2 NW BENEDICT	YORK	NE	4103	9763	ONGROUND CONE TORNADO. (GID)
2247	6 SE UTICA	SEWARD	NE	4083	9726	SPOTTER REPORTED TORNADO ON THE GROUND. (OAX)
2300	3 NE RISING CITY	BUTLER	NE	4123	9726	(OAX)
2305	6 NE ASHTON	HOWARD	NE	4131	9871	(GID)
2308	3 SW BARTLETT	WHEELER	NE	4185	9859	(LBF)

Nebraska and EF5 (F5) Tornadoes

noreply@blogger.com (Ken Dewey) — Tue, 21 May 2013 18:27:00 +0000

The tornado that occurred yesterday, May 21, 2013 in Moore, OK was rated as an EF5 (or F5 on the old Fujita scale).

Has Nebraska ever had a tornado of this magnitude?

The answer is yes, during the evening of May 5, 1964.

An F5 tornado touched down in central Nebraska with a path extending from Adams County to the NW corner of Butler County (near Hastings, NE to Columbus, NE).

This tornado occurred at 0030 UTC May 6, 1964. However, UTC (Universal Time Coordinates) is 5 hours later than CDST, so the actual time in our time zone was 7:30 pm CDST, May 5, 1964.

There were 4 deaths and 50 injuries as a result of this tornado.
The path length of this tornado was 79.7 miles.

The following map shows the location of the F5 tornado in Nebraska.

We have had three other tornadoes in Nebraska that were just under the magnitude of an F5 tornado, the F4 tornado in Omaha on May 3, 1975; the Locust Street June 3, 1980 tornado in Grand Island and the F4 Hallam tornado on May 22, 2004. There is also the March 1913 Omaha tornado which is unrated but has destruction rivaling what we have seen this year in Moore, OK.

Using Radar to Estimate Precipitation

noreply@blogger.com (Ken Dewey) — Tue, 21 May 2013 17:16:00 +0000

Did you know that we can estimate precipitation totals without a rain gauge? Meteorologists have the ability to analyze radar data and estimate the accumulated precipitation totals.

The following map shows the radar estimated precipitation for the Nebraska Region.
Time period: 12Z (7am CDST) May 18, 2013 to 12Z (7am CDST) May 19, 2013.
Nebraska is in the center of the map with portions of the surrounding states. Look carefully to see the state outline and county outlines. Right to left: LNK is Lincoln, BBW Broken Bow,
LBF is North Platte, & CYS is Cheyenne, WY.

The following map shows the radar estimated precipitation for the Conterminous U.S.
Time period: 12Z (7am CDST) May 18, 2013 to 12Z (7am CDST) May 19, 2013.

The following map shows the radar estimated precipitation for the Nebraska Region.
Time period: 12Z (7am CDST) May 19, 2013 to 12Z (7am CDST) May 20, 2013.

The following map shows the radar estimated precipitation for the Conterminous U.S.
Time period: 12Z (7am CDST) May 19, 2013 to 12Z (7am CDST) May 20, 2013.

Although the most accurate precipitation measurement procedure is to use rain gauges, this process of estimating the rainfall using radar data is quite useful, especially for areas without a dense observational network of rain gauges.

May14, 2013, Nebraska: Hottest for so early in the Season

noreply@blogger.com (Ken Dewey) — Wed, 15 May 2013 03:51:00 +0000

May 14, 2013: Record Breaking Heat in Nebraska

Lincoln set a record high today of 100F breaking the old record of 96F set in 1915. This was the earliest in the season that Lincoln has seen 100F or higher with 127 years of data (1887-2013). This is in sharp contrast to Lincoln's record low of 31F just two days earlier. The previous earliest 100F or higher was May 24 (1967).

Omaha set a record high today of 101F breaking the old record of 96F set in 1915. This was the earliest in the season that Omaha has seen 100F or higher with 143 years of data (1871-2013). The previous earliest 100F or higher was May 29 (1934).

Grand Island set a record high today of 102F breaking the old record of 99F set in 1941. This was the earliest in the season that Grand Island has seen 100F or higher with 119 years of data (1895-2013). The previous earliest 100F or higher was May 20 (1925).

However, these were not the warmest locations in the state. The highest temperature observed today was the 108F in Tekahma, Nebraska. Wahoo, NE, hit 104F, Wayne, NE and York, NE hit 103F; Grand Island, NE and Columbus, NE hit 102 F.

Was the 108F in Tekamah a state record for the warmest ever observed temperature for the month of May? No, the warmest ever Nebraska May temperature was 110F in Broken Bow in 1895.

There is a listing of high temperatures for today below the three maps.

Map of NWS Observed High Temperatures for May 14, 2013.
Note Lincoln, NE is not plotted on this map

Observed High Temperatures (in deg. F) in Nebraska on May 14, 2013:

BVN : ALBION AIRPORT : 100

AUH : AURORA AIRPORT : 102

BIE : BEATRICE AIRPORT : 96

BTA : BLAIR AIRPORT : 102

BBW : BROKEN BOW AIRPORT: 97

OLU : COLUMBUS AIRPORT : 102

FET : FREMONT AIRPORT : 101

GRI : GRAND ISLAND ARPT : 102

HSI : HASTINGS AIRPORT : 96

HJH : HEBRON AIRPORT : 98

HDE : HOLDREGE AIRPORT : 99

IML : IMPERIAL AIRPORT : 98

EAR : KEARNEY AIRPORT : 99

LXN : LEXINGTON AIRPORT : 99

LNK : LINCOLN AIRPORT : 100

MCK : MCCOOK AIRPORT : 100

OFK : NORFOLK AIRPORT : 103

LBF : NORTH PLATTE ARPT : 97

OFF : OFFUTT AFB : 99

OGA : OGALLALA AIRPORT : 96

OMA : OMAHA/EPPLEY : 101

MLE : OMAHA/MILLARD : 100

ONL : O`NEILL AIRPORT : 94

ODX : ORD AIRPORT : 100

PMV : PLATTSMOUTH ARPT : 100

TQE : TEKAMAH AIRPORT : 108

OAX : VALLEY NWS OFFICE : 100

AHQ : WAHOO AIRPORT : 104

LCG : WAYNE AIRPORT : 103

JYR : YORK AIRPORT : 102

Lincoln, NE, Latest Spring Freezes 1887-2013

noreply@blogger.com (Ken Dewey) — Sun, 12 May 2013 16:15:00 +0000

Headline: "May 12, 2013 saw a Record Low of 31 F in Lincoln, Nebraska"

This breaks the old breaking the record of 32 F set in 1946.
There are 127 years of data (1887-2013).

This is the 6th latest freeze in Spring for Lincoln, NE.

This record low raises the question of "What are the latest days in Spring with
freezing temperatures in Lincoln, NE"?

Here is a listing of the days with 32F or colder starting with today, May 12, 2013.

May 12, 2013: 31 F
May 13, 1997: 27 F
May 14, 1907: 32 F
May 15, 1907: 31 F
May 16, 1940: 31 F
May 29, 1947: 32 F

LINK to all the Lincoln, NE, daily records

The following map shows the May 12, 2013 low temperatures for our region. Lincoln, NE is not plotted on the map but Omaha, NE, is plotted.

Year 2013 Nebraska Tornado Totals as of May 5, 2013

noreply@blogger.com (Ken Dewey) — Mon, 06 May 2013 18:47:00 +0000

Nebraska Tornadoes Year to date as of May 5, 2013:

March 19, 2013: A land spout tornado report near Shelton, NE.
March 29, 2013: Two tornado reports (10:57 & 10:59pm) near Sutherland, NE
(may be the same tornado, i.e. one instead of two tornadoes)
April 8, 2013: One tornado report near Benkleman, NE.

Here is a graph of the normal monthly frequency of tornadoes in Nebraska.
The 2013, 2012, and 2011 data compared to the normals are below the graph.

Year 2012 Obs.; Norm.
February 2; 0

March 6; 1

April 25; 3

May 6; 12

June 1; 15

July 2; 6

August 1; 3

September 1; 1

October 0; 1

Total 44; 42

Year 2011 Obs.; Norm.
February 0; 0

March 1; 1

April 0; 3

May 13; 12

June 25; 15

July 3; 6

August 13; 3

September 0; 1

October 0; 1

Total 55; 42

Obs. = Observed; Norm. = Normal

The May 27-29, 1947 Nebraska Snowstorm

noreply@blogger.com (Ken Dewey) — Fri, 03 May 2013 14:17:00 +0000

May 2, 2013 An unusual May snowfall blankets Lincoln, NE. Photo by Ken Dewey

On May 1-2, 2013 Lincoln, NE received 2.7 inches of snowfall (LINK: May 1-2, 2013 Lincoln Snowfall). This was only the 3rd time that there has been measureable snowfall in the Capitol city since 1900. The latest recorded snowfall in Lincoln was on May 3-4, 1967 with a total of 3.0 inches.

May 1947 Snow Storm:
In late May1947 a major snowstorm spread from Nebraska into the Great Lakes region. Although this snowstorm missed Lincoln, NE, it buried central and northern Nebraska with almost a foot of snowfall.

Here is a report with a snowfall map produced by Jeff Boyne, NWS, LaCrosse, WI.

Check it out and imagine what it must have been like with trees in full leaf, gardens planted, etc. and then this major winter-like snowstorm hits much of Nebraska just a few days before June!

The Nearly Forgotten Snow Storm of May 27-29, 1947
Jeff Boyne, NWS La Crosse Climate Services Focal Point

Through the years, this late season snow storm has been purged from memories of many people in northeast Iowa, southeast Minnesota, and western Wisconsin. Maybe it is that people do not want to think about snow in late May or that the snow quickly melted, but very few remember this storm. If it was not for this author stumbling upon a 9 inch snow amount in Viroqua, Wisconsin this reminder that snow storms can occur this late in the spring in the Upper Mississippi Valley may have never been written.
On the morning of May 27, 1947, a developing low pressure system was located over central Nevada. It was this low which would be responsible for the snow storm over the Central Plains, Upper Mississippi Valley, and Upper Michigan from May 27th through May 29th. A strong arctic high pressure system was located over the Mackenzie Basin in northwest Canada. This high would provide the cold air needed for a winter storm to develop. A mixture of rain and snow developed over Colorado and Wyoming during the day on May 27th and changed to all snow during the night as the low deepened and moved slowly east through southern Colorado.

On the morning of the 28th, the high pressure center had moved rapidly south to southern Saskatchewan. This high pressure area brought unprecedented cold for late May to North Dakota. Temperatures fell to as low as 15 degrees at Eckman, which is located near the Canadian border. In addition, the mercury fell to 23 degrees at Bismarck which is the lowest ever recorded there after May 20th. Meanwhile, below freezing temperatures were found across Montana, Wyoming, northeastern Colorado, western Nebraska, northern Minnesota, and western South Dakota. The sub freezing temperatures caused a partial to total loss of fruits and tender plants. During the day, this cold air surged southward across eastern Nebraska, eastern South Dakota, Iowa, southern Minnesota, and Wisconsin. Many cold maximum temperatures were established across the region for the day.

At the same time this was occurring, the area of low pressure was continuing to strengthen as it moved east through southern Kansas. From the evening of the 27th through the 28th, this low produced a 6-12" snow band from southeast Wyoming east across northern Nebraska into northwest Iowa. The heaviest snow in this band was found in Alliance and Harrison, Nebraska where 12" had fallen. The weight from the heavy wet snow caused considerable damage to power lines, telephone lines, telegraph lines, trees, and shrubs.

During the late afternoon and evening of May 28th, the surface low began to move northeast across northern Missouri, northwest Illinois, and southeast Wisconsin. The reason for this change in direction was due to a strong upper level disturbance that had dropped into the base of the upper level trough over Nebraska during the day. This upper level disturbance caused an amplification of the upper level ridge over the Ohio Valley and much of New England. As a result, temperatures in this region climbed into the 80s instead of the 50s and 60s which were seen the day before. However on the cold side of the system, temperatures remained in the 30s and 40s in the Upper Mississippi Valley. In addition to the cold temperatures, rain changed to snow across southern Minnesota, northeast Iowa, and across much of Wisconsin. This was the latest snow ever reported in a season in this area, with some places experiencing their biggest May snow storm on record.

From the late afternoon of the 28th into the early morning hours of the 29th, 7-10" of snow fell across Allamakee County in northeast Iowa, and Vernon, Crawford, southern Monroe, and Richland Counties in southwest Wisconsin. The heaviest snowfall amount was 10" in Gays Mills, WI. Meanwhile, a 7-9" band of snow fell across northern Adams, Waushara, Winnebago, Outagamie, and Waupaca Counties in central and east central Wisconsin. The weight of the heavy snow caused severe damage power lines, telephone lines, bushes, and trees.

May 1-2, 2013 Snowfall in Lincoln, NE

noreply@blogger.com (Ken Dewey) — Thu, 02 May 2013 16:46:00 +0000

How rare is snowfall in Lincoln during May?

Last night’s snowfall (May 1-2, 2013) in Lincoln was only the third time since 1900 (114 years of data) that it has snowed in May in Lincoln.

These are the only May snowfalls of record in Lincoln:

May 3, 1907: 2.2 inches
May 3-4, 1967: 3.0 inches

May 1-2, 2013: 2.7 inches

The snow on May 1-2, 2013, was the first measurable May snowfall in 46 years in both Lincoln and Omaha.

This snowfall was also a "thunder snow" with lightning and thunder at the peak of the snowfall.

What makes this event even more dramatic is that the area had temperatures in the mid 80's F just two days before the snowfall (April 29, 2013). Note the map below.

The local Garden Centers were especially hit hard by this event with the tender vegetation exposed to the freezing temperatures and snowfall (note the photos below).

Other snowfall totals across the region include:

Omaha/Eppley 3.1 inches

NWS Valley 3.0 inches

Lincoln Airport 2.7 inches

Offutt AFB 1.6 inches

North Platte Airport 0.9 inches

Grand Island Airport 0.7 inches

Hastings Airport 0.3 inches

Four radar images one static at 11:50 EDT (10:50 CDT),

the other three are animations for the evening of May 1, 2013

Photos from Lincoln, May 1 and 2, 2013:

All Images © Ken Dewey, Applied Climate Science,
School of Natural Resources, University of Nebraska-Lincoln

Lincoln, NE, April 2013 Climate Summary

noreply@blogger.com (Ken Dewey) — Wed, 01 May 2013 15:46:00 +0000

April 2013 was the 9th coldest April on record for Lincoln, NE with 127 years of data (1887-2013).

Lincoln Top Ten Coldest Aprils

Rank  Value(F) Year
  1    43.5    1907
  2    44.0    1920
  3    44.6    1944
  4    45.1    1997
  5    45.3    1983
  6    45.5    1904
  7    45.9    1950
  8    46.0    1951
  9    46.1    2013
 10    46.4    1909

Here are the summary statistics for April 2013 with a graph below the statistics.

April 2013 Temperature Statistics
Average High Temperature 58.8 F (5.5 degrees BELOW Normal)
Average Low Temperature 33.4 F (5.4 degrees BELOW Normal)
Mean Temperature 46.1 F (5.5 degrees BELOW Normal)
Note: Mean temperature = the average of all the highs and lows
Number of days ABOVE Normal = 9
Number of Days BELOW Normal = 19
Number of Days exactly Normal = 2
Highest temperature 84 F on April 29
Lowest temperature 18 F on April 2

April 2013 Precipitation Statistics
Total all precipitation 4.02 inches (1.31 inches ABOVE Normal)
Note: All precipitation = rain plus melted snow water equivalent
Total Snowfall 0.6 inches (0.8 inches BELOW Normal)
Heaviest precipitation 1.19 inches on April 22

The following graph shows the Lincoln, NE, April Daily high and low temperatures compared to normal.

The Red Line is the normal high and the Blue Line is the normal low.
The top of each vertical bar is the high for the day and the bottom of each vertical bar is the low for the day.All data in this graph are from the National Weather Service and HPRCC data archives.

Lincoln, NE, Snow in May?

noreply@blogger.com (Ken Dewey) — Wed, 01 May 2013 01:49:00 +0000

The forecast on April 30. 2013 has snow in the forecast for May 1 and May 2.
The forecast panel below was created as of 7:54pm CDST on April 30, 2013.

How rare would measurable snow in May be for Lincoln, NE?

Yes, we have had measurable snowfall in May. Here are the two times that this has happened since 1900:

Latest measurable snowfalls:
May 3, 1907: 2.2 inches
and, May 3-4, 1967: 3.0 inches .

For more information about snowfall in Lincoln checkout these links:

Lincoln's Snowfall Climatology
Lincoln's Snowfall Statistics

Lake McConaughy, Nebraska, Drought Update

noreply@blogger.com (Ken Dewey) — Mon, 29 Apr 2013 14:55:00 +0000

An update for Lake McConaughy in western Nebraska (Friday April 26, 2013)

April 26, 2013: Volume = 1,093,600 acre feet (63.5% of capacity)
April 26, 2012: Volume = 1,432,800 acre feet (82.4% of capacity)

As noted in the last posting (LINK), the water content in the snow pack of the mountains in southeastern Wyoming ranges from 66% to 102% of normal. Lake McConaughy is fed water from the North Platte River which originates in the mountains of eastern Wyoming. Unless timely spring snowfall and rainfall return to this area which feeds water into the North Platte, it is unlike that we will see a recovery of Lake McConaughy this year.

The next graph (below) shows the inflow of water into Lake McConaughy. The purple line is the average inflow and the blue line is the current inflow magnitude. It is obvious on the graph that the inflow this year into Lake McConaughy has been running much below average (with the exception of early April when the inflow briefly approached the average magnitude.

(data source: http://www.cnppid.com/Elevation_Flows2.htm)

SNOTEL Water Update for the Western U.S.

noreply@blogger.com (Ken Dewey) — Fri, 26 Apr 2013 19:35:00 +0000

The following map is prepared weekly by the USDA/NRCS National Water and Climate Center. The weekly snowpack and drought update report (which is the source of this map) is found at the following address: http://www.wcc.nrcs.usda.gov/cgibin/water/drought/wdr.pl

The map below shows the Water Year, October 1, 2012 to date (April 25, 2013) precipitation as a % of normal. The water amount is determined from the SNOTEL surveys done throughout the mountainous western U.S.

The recent snowfalls and rainfalls in the western U.S. have greatly improved conditions for much of Colorado and almost all of Wyoming. Wyoming has (since October 1, 2012) from 66% to 102% of normal precipitation and Colorado for the same time period currently has 69% to 91% of normal precipitation These two states are critically important since they send the melt water from the spring melt in the mountains into the South Platte and the North Platte Rivers in Nebraska. This water is important in Nebraska since it is used for agriculture, recreation and several power plants.

Lake McConaughy is one of the largest reservoir in Nebraska and is fed by the North Platte River coming out of Wyoming. It currently (as of April 27, 2013) has a volume of 1,093,600 acre feet which is at 63.5% of capacity. Link to Lake McConaughy Water Data.

A year ago on this date Lake McConaughy had a volume of 1,432,800 acre feet or 82.4% of capacity.

April 23, 2013: Is the Great Plains Drought Over?

noreply@blogger.com (Ken Dewey) — Wed, 24 Apr 2013 15:28:00 +0000

With the very active weather pattern the last few weeks and frequent rainfall (and even some snowfalls) in Nebraska and the Great Plains, it would seem to many that the drought in our area might have ended.

However, even if the topsoil is wet and there is some standing water in some fields, more of the long term deficit must be erased before we can officially declare that the current drought has ended.

The following map covers the time period April 24, 2012 through April 23, 2013 and shows (in inches) the current 12-month deficit in precipitation (departure from normal) for the High Plains region. Much of Nebraska has a deficit of 8 to 12 inches and parts of central Nebraska (in red) still have a deficit in excess of 12 inches (12 to 16 inches)

The following map shows the 12 month departure from normal precipitation as a percent of normal. Much of Nebraska has had between 50 and 70% of normal precipitation during the past 12 months and central Nebraska (dark red) has an area which has only received between 25 and 50% of normal precipitation.

The following two maps are for the same time period but for a larger region, the conterminous 48 states.

Cold Spring

noreply@blogger.com (Eric Hunt) — Sun, 21 Apr 2013 05:03:00 +0000

If you think it seems like we have been perpetually stuck in early March this year, you are not alone. It has been consistently cold here for quite a while and other than green grass, it's hard to find a sign of spring here in east central Nebraska. However, this is not the case in all of the Midwest. Most of the eastern corn belt/ lower Midwest have had somewhat typical spring temperatures. But if that makes you jealous, just consider that we could be in North Dakota. Grand Forks has still not managed to crack 40F this month.

Anyway, given the relatively persistent pattern the past few weeks, two things stand out in Big 10 country: a) the unusually high rainfall totals in some places and b) the temperature difference across the conference. First the rainfall, which has been excessive in much of Iowa, northern Illinois, and northern Indiana. Top 4 rainfall totals this month (as of 18 April):

1. Iowa City, IA: 8.30 in.
2. Evanston, IL: 7.83 in.
3. West Lafayette, IN: 6.73 in.
4. East Lansing, MI: 6.19 in.

Where has it been coldest? The Twin Cities easily takes the cake here but the next three haven't been that mild either (as of 18 April):

1. Minneapolis-St.Paul, MN: 36.4F
2. Madison, WI: 40.3F
3. East Lansing, MI: 41.4F
4. Lincoln, NE: 43.5F

All of the above locations, except East Lansing, have had measurable snow multiple times this month. The Twin cities has had over 13 inches of it! As mentioned earlier, some places in the conference have had a decently warm April. Here are the top 4 average temperatures for April (through 18 April):

1. Bloomington, IN: 54.7F
2. Columbus, OH: 54.5F
3. Champaign, IL: 51.1F
4. West Lafayette, IN: 50.3F

If we consider the D.C. area for U of Maryland, the numbers in Indiana and downstate Illinois wouldn't look quite as impressive as they have had multiple days in the 80's and hit 90 a week ago. So there has been warm weather, just not around here. But never fear, a cold spring in the western Corn Belt is not indicative of a cool summer.

March 2013 Global Climate Summary

noreply@blogger.com (Ken Dewey) — Thu, 18 Apr 2013 17:27:00 +0000

March 2013 Global Climate Summary (from NOAA/NCDC)

Note: The January 1-March 31, 2013 Summary is also included at the end of this posting.

Global Highlights

The combined average temperature over global land and ocean surfaces for March 2013 tied with 2006 as the 10th warmest on record, at 0.58°C (1.04°F) above the 20th century average of 12.3°C (54.1°F).
The global land surface temperature was 1.06°C (1.91°F) above the 20th century average of 5.0°C (40.8°F), the 11th warmest March on record. For the ocean, the March global sea surface temperature was 0.41°C (0.74°F) above the 20th century average of 15.9°C (60.7°F), making it the ninth warmest March on record.
The combined global land and ocean average surface temperature for the January–March period (year-to-date) was 0.58°C (1.04°F) above the 20th century average of 12.3°C (54.1°F), the eighth warmest such period on record.

Summary:

The globally-averaged temperature across the world's land and ocean surfaces was 0.58°C (1.04°F) above the 20th century average of 12.7°C (54.9°F), tying with 2006 as the 10th warmest March since records began in 1880. Both the Northern and Southern Hemispheres were also 10th warmest for March.
Globally, land surface temperatures were 1.06°C (1.91°F) above average (11th warmest on record), but there were some marked temperature anomaly differences around the world. The Arctic Oscillation (AO), a large-scale climate pattern that can influence temperatures in the Northern Hemisphere, was strongly negative during the month, and in fact reached a monthly-averaged record low for March. This negative phase was associated with frigid Arctic air spilling southward into the Northern Hemisphere middle latitudes. Particularly, it was either cooler or much cooler than average across the eastern half of the United States as well as most of Europe, European Russia, and northern Siberia, according to the Global Land & Ocean Temperature Percentiles map above. Parts of northeastern Europe and western Russia observed temperatures that were at least 5°C (9°F) lower than average. This phase of the AO also contributed to much warmer than average and even record warm temperatures in northeastern Canada and southeastern Greenland. A large swath of China also saw record warm temperatures. Parts of these regions were at least 5°C (9°F) above average. Additionally, several regions in central and northern Africa in the 0°–20°N latitude belt were record warm. Overall, the 20°N–20°S global tropical latitude belt was the third warmest on record for that region during March, at 1.18°C (2.12°F) above average. Most of northern Africa, along with northern South America and northern Australia, were also much warmer than average. In the Southern Hemisphere, Argentina observed temperatures that were cooler to much cooler than average.

Global Temperature Anomalies January 1-March 31, 2013:

With ENSO-neutral conditions holding during the first three months of 2013, the January–March global temperature across land and ocean surfaces was the eighth warmest on record, at 0.58°C (1.04°F) above the 20^th century average. The global land temperature ranked seventh warmest, with the Southern Hemisphere observing its second warmest such period, behind 2010, and the Northern Hemisphere having its 12^th warmest January–March temperature over land on record. Parts of northern Australia and equatorial Africa were record warm for the period. The global ocean temperature was eighth warmest for January–March, with a large section of the Indian Ocean south of Australia having record warmth. No record cold regions over land or water were observed for the first quarter of the year.

March 2013 U.S. Climate Highlights

noreply@blogger.com (Ken Dewey) — Tue, 16 Apr 2013 18:50:00 +0000

March 2013 U.S. Climate Review

Nebraska Rankings:

Precipitation: 51st driest or conversely 68th wettest out of 119 years of data (1890-2013).

That is March 2013 precipitation in Nebraska was "Near Normal".

Temperatures: 36th Coldest or conversely 83rd Warmest out of 119 years of data (1`890-2013)

That is March 2013 temperatures in Nebraska were "Below Normal".

From NOAA/NCDC:
U.S. climate highlights - March

Most of the eastern U.S. was cooler than average during March, with the exception of New England, which was slightly warmer than average. Eleven states in the Ohio Valley, along the Gulf Coast, and in the Southeast had March temperatures that were among their ten coolest. Alabama, Florida, Georgia, North Carolina, and South Carolina had March 2013 temperatures that were cooler than January 2013.
Temperatures were above average for parts of the West. Arizona, California, and Nevada each had March temperatures ranking among their ten warmest. Above-average temperatures were also observed in Washington, Oregon, Idaho, Utah, and New Mexico.
A large area of the contiguous U.S. had near- to below- average precipitation during March. The West, Southern Plains, Gulf Coast, and Northeast were particularly dry. Louisiana had its fourth driest March and Wyoming had its fifth driest. Minnesota was the only state with above-average March precipitation.
Several storms brought late-season snowfall to the eastern two-thirds of the country. According to data from the Rutgers Global Snow Lab, the March snow cover extent for the contiguous U.S. was the 10^th largest in the 47-year period of record. However, snowpack, an important water resource in the West, was below-normal in the Sierra Nevada Mountains as well as the Central and Southern Rockies.
According to the April 2 U.S. Drought Monitor report, 51.9 percent of the contiguous U.S. was experiencing moderate-to-exceptional drought, smaller than the 54.2 percent at the end of February, but significantly higher than 36.8 percent at the beginning of April last year. Drought conditions improved in parts of the Southeast, as well as the eastern edge of the core drought areas in the Central and Southern Plains due to increased precipitation over the past three to six months. Drought remained entrenched across the rest of the Great Plains and interior western states.

Lincoln, NE, Daily Frequency of Snowfall

noreply@blogger.com (Ken Dewey) — Fri, 12 Apr 2013 15:53:00 +0000

Lincoln, NE, Snowfall Climatology: Daily Frequency of Snowfall

The last posting illustrated how frequently it snows in April which was prompted by the snowfall of April 10-11, 2013.

This posting looks at the daily frequency of snowfalls for the period September 15 though May 15 and for the years 1948-2013 (66 years).

The earliest measurable snowfall was on September 29, 1985 and the latest measurable snowfall was on May 3-4. 1967.

The following graph was created to illustrate how often it has snowed in Lincoln on each calendar day from mid September through Mid May.

Here is a link to the complete data set: Daily Snowfall Frequency, 1948 through Spring 2013

The calendar day with the highest frequency of snowfall (18 times out of 66 years) in Lincoln is calendar day January 20. February 13 has seen snowfall 17 times and January 26 has seen snowfall 16 times out of the past 66 years.

It is interesting to see that there are some days in the middle of winter that have had relatively very few snowfall occurrences.

For example, December 29 has only seen snowfall 4 times since 1948 yet December 28 has seen snowfall 13 times and December 27 has seen 14 snowfalls since 1948.

January 27 with only 8 snowfall occurrences and January 28 with only 5 occurrences since 1948 also stand out as having very low snowfall frequencies. These two calendar days are surrounded by days with 2 to 3 times more frequent snowfalls.

There appears to be no reason for these calendar days that stick out with very relatively low snowfall frequencies.

How Rare is Snow in April in Lincoln, NE?

noreply@blogger.com (Ken Dewey) — Thu, 11 Apr 2013 15:34:00 +0000

April Snowfall Climatology for Lincoln, NE

A snow covered Lincoln, NE, April 11, 2013 (Photo by Ken Dewey)

A garden nursery in Lincoln, NE with snowfall covering the tender plants (Photo by Ken Dewey)

Number of years with and without measurable snowfall, January 1900 - through April, 2013

Month	With Snowfall	Without Snowfall	Number of Years
January	111	3	114
February	109	5	114
March	99	15	114
April	53	61	114
May	3	110	113

September	1	112	113
October	18	95	113
November	82	31	113
December	110	3	113

The above table is from our website: Lincoln, NE, Snowfall Statistics:

There are 114 years of monthly data for Lincoln, NE and 53 times out of 114 years, Lincoln received measurable snowfall in the month of April. That is, Lincoln has had measurable snowfall in April 46% of the time and there was no measurable snowfall in April 54% of the time.

Daily Snowfall Climatology for for Lincoln, NE
Although Monthly snowfall totals exits back to 1900, daily snowfall data exist back only to 1948 for Lincoln, NE.

Looking at the period 1948-2013 (66 years);

Latest snowfall in Spring: May 4, 1967, 3.0 inches

It has snowed in April on 52 days since 1948.
That is 52 days out of 1,980 days or it has snowed only 3% of all April days in Lincoln.

The last April snowfall before this year was 4.6 inches on April 6-7, 2003

Normal April snowfall = 1.4 inches

2012-2013 Snowfall total = 24.7 inches

The following table shows the frequency of snowfalls
for each day in April for the period 1948 through 2013

April	Frequency
1	5
2	5
3	6
4	1
5	3
6	2
7	2
8	4
9	4
10	1
11	3
12	5
13	1
14	3
15	0
16	1
17	0
18	0
19	0
20	1
21	1
22	0
23	1
24	0
25	0
26	0
27	0
28	1
29	1
30	1

Lake McConaughy Drought Update, April 4, 2013

noreply@blogger.com (Ken Dewey) — Thu, 04 Apr 2013 15:58:00 +0000

April 4, 2013 Lake McConaughy Drought Update:

As of 7am April 4, 2013: Volume = 1,143,400 acre feet which is 65.6% of capacity.
Last year, April 4, 2012: Volume = 1,448,900 acre feet which was 83.1% of capacity.

The following two graphs show the elevation of Lake McConaughy for the last 12 months as well as since 1941.

Although the current level of the reservoir is midway between capacity and the low mark of 2005-2007, the concern at this time is the below normal snow pack in Wyoming that feeds into the North Platte River and ultimately the Lake McConaughy reservoir. The last image on this page which shows that the water content in the snow pack that would feed into the North Platte River. No where in the Platte River basin in Wyoming (or Colorado) is there above normal water content in the current snow pack.

Photo by Ken Dewey, UNL

High Plains and U.S. Drought Update April 1, 2013

noreply@blogger.com (Ken Dewey) — Wed, 03 Apr 2013 15:30:00 +0000

Drought Update for the High Plains and the U.S.

Have the recent rainfalls and snowfalls ended the drought across our region?

No, there are still huge deficits that need to be covered.

We are headed into what is normally the wettest time of the year for the Great Plains, so there is hope that these deficits might be erased. Normally the three wettest months in Nebraska are May, June and July.

March 2013 Maps:
Much of the High Plains continued to have below normal precipitation during March 2013. It was also drier than normal across almost all of the western 1/2 of the U.S. during March 2013.

April 1, 2012 - March 31, 2013 Maps:
Going back for the lat 12 months, ALL of Nebraska and almost all of the High Plains has experienced a deficit of precipitation. The deficit exceeds 12 inches in the center of Nebraska as well as in portions of Wyoming, Colorado and New Mexico. Looking at the U.S. maps, the greatest deficit is in a north-south zone stretching from Nebraska through Kansas, Oklahoma and into far southern Texas.

March 2013

April 1, 2012 - March 31, 2013

March 2013 Lincoln, NE, Climate Summary

noreply@blogger.com (Ken Dewey) — Tue, 02 Apr 2013 14:18:00 +0000

March 2013 Lincoln, NE, Climate Summary
Data Archive 1887 through 2012, 126 years of data

March 2013 Highest Temperature 71F (March 29)
Record Highest temperature 91 F (March 25, 1907 and March 31, 2012)

March 2013 Lowest Temperature 8F (March 13)
Record Lowest temperature -19 F (March 4, 1978)

Average High 46.3 F (6.0 degrees F BELOW Normal)
Average Low 23.4 F (4.5 degrees F BELOW Normal)
Mean Temperature (average of the highs and lows) = 34.8 F (5.3 degrees F BELOW Normal)

March 2013 was the coldest March since 2002.
March 2013 (34.8 F) was 20.2 degrees COLDER than last year, March 2012 (55.0 F)
March 2013 was the first colder than normal month since October 2012.

Total precipitation = 2.12 inches (0.19 inches ABOVE Normal)
Total Snowfall = 7.4 inches (2.5 inches ABOVE Normal)

The Red Line is the normal high and the Blue Line is the normal low.
The top of each vertical bar is the high for the day and the bottom of each vertical bar is the low for the day.

The following graph is for March 1-31, 2012 and shows the large contrast between march 2013 and March 2012. The same scale for temperature 5F to 95 F is used on both charts so that they can be directly compared to each other.

Spring Climate Outlook

noreply@blogger.com (Ken Dewey) — Thu, 21 Mar 2013 17:52:00 +0000

March 21, 2013: Spring Outlook for Temperatures, Precipitation and Flooding

NOAA issued the three-month U.S. Spring (April 1-June 30, 2013) Outlook today, stating that odds favor above-average temperatures across much of the continental United States, including drought-stricken areas of Texas, the Southwest and the Great Plains. Spring promises little drought relief for most of these areas, as well as Florida, with below- average spring precipitation favored there. Meanwhile, river flooding is likely to be worse than last year across the country, with the most significant flood potential in North Dakota.
"This outlook reminds us of the climate diversity and weather extremes we experience in North America, where one state prepares for flooding while neighboring states are parched, with no drought relief in sight," said Laura Furgione, deputy director of NOAA's National Weather Service. "We produce this outlook to help communities prepare for what's likely to come in the next few months and minimize weather's impacts on lives and livelihoods. A Weather-Ready Nation hopes for the best, but prepares for the worst." The U.S. Spring Outlook identifies the likelihood of spring flood risk and expectations for temperature, precipitation and drought. The outlook is based on a number of factors, including current conditions of snowpack, drought, soil moisture, streamflow, precipitation, Pacific Ocean temperatures and consensus among climate forecast models.

Spring Equinox and the Four Seasons

noreply@blogger.com (Ken Dewey) — Thu, 21 Mar 2013 15:30:00 +0000

Spring began at 6:02 A.M. (CDT) on March 20, 2013 in the Northern Hemisphere. The technical name is the "Vernal Equinox" and in the fall it is called the "Autumnal Equinox". The seasons are reversed in the Southern Hemisphere so this was the start of Fall or autumn for them.

The word equinox is derived from the Latin words meaning “equal night.” Days and nights are approximately equal everywhere and the Sun rises and sets due east and west (making driving on East-West roads difficult at sunrise and sunset). Due to the way we measure sunrise and sunset, i.e. at what point the sun's disk has risen and set, there are a few extra minutes at the Equinoxes so it is not exactly 12 hours of daylight.

As we head toward the first day of Summer (the Summer Solstice) the sun in Lincoln rises further and further north and sets further and further north on the horizon. By June the sun is rising in the northeast east and setting in the northwest sky in Lincoln. For those lucky enough to travel to the Arctic during the summer, the sun in June is visible for all 24 hours there and will be directly north around midnight (but very low in the sky). This area is often referred to as the "Land of the Midnight Sun"

Lincoln will have around 15 hours of daylight by June which is in contrast to our minimum of around only 9 hours of daylight in December (see exact totals below here)..

Lincoln, NE: Start of each Season with Sunrise and Sunsets for 2013:
Spring Equinox: 6:02 am CDST, March 20: Sunrise 7:30 am CDST; Sunset 7:39pm CDST
Summer Solstice: 12:04 am, CDST, June 21: Sunrise 5:55am CDST; Sunset 9:02pm CDST
Autumnal Equinox: 3:44 pm CDST, September 22: Sunrise 7:14 am CDST; Sunset 7:23pm CDST
Winter Solstice: 11:11am CST, December 21: Sunrise 7:48 am CST; Sunset 5:02pm CST

Lincoln's longest daylight length = June 21 = 15 hours and 7 minutes
Lincoln's shortest daylight length = December 21 = 9 hours and 14 minutes

The actual starting times and dates of the start of each of the seasons changes from year to year.
Here is a link to the exact dates and times of the start of the 4 seasons, present out through future years (NOTE the times are in GMT which is 5 hours later than our time zone during CDST and 6 hours later than us during CST):
Dates and times for the start to the seasons.

Here is a link to an excellent Internet site to create a table for the sunrise and sunset times for any location for a complete year: Sunrise/Sunset Tables for any Location

The following diagram (although not to scale since the sun is actually much larger than the earth) shows the concept of the Northern Hemisphere being pointed toward the sun during our Summer and away from the sun during our winter. This is the cause of the season and results in the variation in daylight during the year and the intensity of solar radiation received at the earth's surface.