A Day for the Weather Record Book

It is hard to believe that there is still a week left in April, as the weather is behaving more like June or July.  Not only are temperatures running near/above record level,  high based afternoon thunderstorms are developing in response to the heating.

Here is the Monday evening 500mb chart showing the huge upper ridge over the west and deep, cold trough across the eastern states.

To provide some perspective as to the how warm the temperatures are, the record high  for the month of April at the Bedford climate station going back to 1975 is 75 degrees.  While at the Afton COOP station the highest for the month of April going back to 1957 is 78 degrees.

Following are maximums recorded across Star Valley on Monday

Etna Elementary         82

Thayne Elementary     82

Star Valley Ranch        79
   
Alpine                          81     

 Smoot                         75

Auburn                         80


Afton                            77

The statement issued by the WFO at Pocatello Monday evening  is of interest:

RECORD EVENT REPORT 
 NATIONAL WEATHER SERVICE POCATELLO ID
 715 PM MDT MON APR 23 2012
 
 ...RECORD HIGH TEMPERATURES SET FOR THE MONTH OF APRIL...
 
  IDAHO FALLS AND POCATELLO BOTH ESTABLISHED HIGH TEMPERATURE RECORDS 
 FOR THE MONTH OF APRIL TODAY.
 
  IDAHO FALLS RECORDED 86 DEGREES TODAY WHICH IS THE ALL TIME APRIL 
 HIGH BREAKING THE PREVIOUS RECORD OF 85 SET ON THE 29TH OF APRIL IN 
 1992. 
 
  86 DEGREES IN POCATELLO TIED THREE PREVIOUS RECORDS OF 86 SET ON 
 THE 21ST IN 1994...29TH IN 1992...AND 25TH IN 1946. 

There is at least one more day of similar weather as the upper high pressure 

remains in place through Tuesday.  However changes will begin Wednesday with not 

only cooler temperatures but an increase chance of thunderstorms. 

By the weekend a trough of low pressure will reside over Wyoming returning Star Valley

to more typical late April conditions. 

500 mb forecast Mid Day Sunday  April 29 2012