May 24, 2012 Platte County, Nebraska Tornado.

May 24, 2012 Platte County, Nebraska Tornado.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OMAHA/VALLEY NEBRASKA
746 PM CDT THU MAY 24 2012

0536 PM TORNADO 2 WNW CORNLEA 41.69N 97.60W
05/24/2012 PLATTE NE EMERGENCY MNGR

 A TORNADO DAMAGED A FARMSTEAD 2 MILES WEST AND 1 MILE NORTH
OF CORNLEA. HOUSE HAD ROOF TAKEN OFF AND MOST OF WALLS
COLLAPSED. TIME APPROXIMATE..

Home that was hit by the tornado

 Aerial view with the tornado track indicated in green.
Map analysis produced by NWS Omaha/Valley, NE

Another view of the tornado damaged home

Another view of the tornado

May 23, 2012 Record Heat in Lincoln, NE

May 23, 2012: Record High of 94 F in Lincoln, NE

A record high of 94 F was observed yesterday in Lincoln, NE.  This was the 9th day this year with highs 90 F or higher in Lincoln, NE.  This ties 1934 for the most number of 90 degree days by May 23 (with 126 years of data).

A significant cool-down is expected today (Thursday May 24) and tomorrow (Friday, May 25), then two more hot days on Saturday (mid 90's) and Sunday (near 90F) then cooler again to end the month of May 2012.  Lincoln residents were not so lucky in May 1934.  High temperaturess for the last days of the month exceeded 90 F and 100 F

Lincoln, NE, High Temperatures, May 1934
May 28, 1934:    93 F
May 29, 1934:  102 F
May 30, 1934:  104 F
May 31, 1934:  103 F
 
Mid summer heat wave temperatures spread across the Great Plains yesterday, May 23, 2012.  The state-wide high temperatures for May 23, 2012 were: 107 F, Dryden, TX; 103 F, Guymon, OK; 102 F, Roswell, NM; 100 F, Dodge City, KS; 96 F, Hebron, NE; and, 94 F, Cherokee, IA. 

The attached map shows yesterday's (May 23, 2012) high temperatures. Note the 111 F south of the TX/Mexico border.

January 1-May 15, 2012 Lincoln Temperature Departures from Normal

Daily Temperature Departures from Normal,

Lincoln, NE, January 1 - May 15, 2012
The attached graph shows the daily temperature departures from the normal for each day.  The length of the column indicates the magnitude of the departure.  If the column is red it is above normal and if the column is blue it is below normal.

For example on January 19, 2012 the high temperature was 16 F and the low temperature was 5 F for a daily average of 11 F which was 13 degrees BELOW the normal for that day of 24 F.  The column on the graph for that day is blue and extends down to a -13 degrees departure from normal.

For example on January 30, 2012 the high temperature was 70 F and the low temperature was 34 F for a daily average of 52 F which was 27 degrees ABOVE the normal for that day of 25 F. The column on the graph for that day is red and extends upward to a +27 degrees departure from normal.

Here is a listing of the total number of days between January 1 and May 15 that had above, below and exactly normal temperatures:

Above: 96 days (71% of the days)
Below:  33 days (24% of the days)
Exactly Normal: 7 days (5% of the days)
Total = 136 days

And, as of May 15, 2012, this is the warmest year on record for that time period with data extending back 126 years to 1887.

Lincoln Year to date - May 14, 2012 - Warmest on record

Year To Date (May 4, 2012) Warmest on Record for Lincoln, NE.

The average temperature for Lincoln for the time period January 1-May 14, 2012 is the warmest on record for Lincoln, NE. 

Here is a listing of the top ten warmest January 1 through May 14 time periods. 
There are 126 years of data extending from 1887 to the current (2012).

Highest Average  Temperature degrees F
Days: 1/1 - 5/14

Rank  Value  Ending Date
  1    45.4    5/14/2012  2    44.1    5/14/1992
  3    43.7    5/14/1946
  4    43.6    5/14/1987,  5/14/1921
  6    42.4    5/14/2000
  7    42.3    5/14/2006
  8    42.2    5/14/1986
  9    42.1    5/14/1934
10    41.9    5/14/1981

Lincoln is not alone in experiencing an extremely unusually warm year.  The attached map shows the temperature departures for the lower 48 states and much of the Great Plains, Midwest and Great Lakes regions have temperature departures from normal in excess of 6 degrees F.  Some areas have a temperature departure in excess of 10 degrees F.  As of today, May 15 there is no sign of a break in this trend with high temperatures in the mid to upper 80's across eastern Nebraska through the weekend.  The temperatures this week are more characteristic or normal for the time period of late June.

A Ten Year U.S. Tornado Climatology

A Ten-Year Tornado Climatology for the U.S.

Because the states vary so much in size, it is better to examine tornado density (number of tornadoes per 10,000 sq. miles).Unless this is done, looking at the tornado total for Kansas and then Texas wold give misleading results since Texas is much larger than Kansas.

This map, produced by the Storm Prediction Center of NOAA highlights the ten year period 2001-2010 and measures the frequency of tornadoes per unit size or area of 10,000 square miles.

The highest density is in Kansas followed by Florida.  Illinois and Iowa have a higher density than Nebraska.

Nebraska has had a total of 524 tornadoes for this time period (see:  http://snr.unl.edu/extremeweather/netornado/Nebraska-Tornado-Totals.asp)
or an average of 52 tornadoes per year during that time period and it's size is 77,358 sq. miles giving it an average of  7 (actual number 6.77) tornadoes per 10,000 sq miles.

April 2012 Statewide Temperature Rankings

April 2012 Climate Summary.  From NOAA/NCDC.
According to NOAA scientists, several warm periods across the nation during April brought the average temperature of the contiguous U.S. to 55°F, 3.6°F above average, marking the third warmest April on record. These temperatures, when added with the first quarter and previous 11 months, calculate to the warmest year-to-date and 12-month periods since record keeping began in 1895. 

The 12-month period of May 2011-April 2012 has a nationally-averaged temperature 2.8°F above the 1901-2000 long-term average, while the January-April 2012 months were 45.4°F, 5.4°F above the long-term average.
U.S. Climate highlights - April 2012

• Warmer than average temperatures were present for a large portion of the nation during April with nine states in the Central and Northeast regions having April temperatures ranking among their ten warmest. Above average temperatures were also present for the Southeast, Upper Midwest and much of the West.
• Eight states - Illinois, Indiana, Kentucky, Michigan, Wisconsin, Ohio, Pennsylvania, and West Virginia - had average April temperatures cooler than their March temperatures. However, these temperatures were still above the long-term average for the month.
• According to the Rutgers Global Snow Lab, the April snow cover extent across the contiguous United States was the third smallest on record, despite the late season Nor'easter which impacted the Northeast with snow near the end of April.

Jan. 1-May 7, 2012 Warmest on Record for Lincoln, NE

January 1 - May 7, 2012 Temperature Departures from Normal in Lincoln, NE
The above graph shows the daily temperature departures from normal for Lincoln, NE, from January 1 through May 7.  Blue columns show the magnitude of below normal temperatures and red columns the magnitude of above normal temperatures for each day.  The actual daily normals vary during the year. 

For example, the observed temperatures for January for January 19, 2012 were a high of 16F, a low of 5F and an average for that day of 11F.  The normal daily average for January 19 is 24F, which means this day had a departure of 13 degrees below normal (BLUE column). 

For example, the observed temperatures for March 26, 2012 were a high of 84F, a low of 58F and an average for that day of 71F. The normal daily average for March 26 is 45 F which means this day had a departure of 26 degrees above normal (RED column).

As of May 7, 2012, the year to date average temperature is the warmest on record.  Here is a listing of the top ten warmest January 1-May 7 time periods, with 126 years of data, 1887-2012.

Lincoln Highest Average Temperature degrees F

Days: January 1 through May 7; Years: 1887-2012

Rank  Value  Ending Date
  1    44.6    5/ 7/2012 
  2    43.2    5/ 7/1946
  3    42.9    5/ 7/1992
  4    42.8    5/ 7/1921
  5    42.2    5/ 7/1987
  6    41.3    5/ 7/2006,  5/ 7/2000,  5/ 7/1981
  9    41.1    5/ 7/1931
10    40.9    5/ 7/1986