Saturday, May 7, 2011

May 9-11 Severe Weather Threat: Major Instability Possible (Issued May 7)

TERMS TO KNOW
CAPE- A measure of instability. Values over 2000 j/kg are considered unstable. Values over 4000 are considered extremely unstable and very dangerous.

Good evening, everyone! I've just been running over the ensembles from the GFS, which is the most reliable, possibly even more reliable than the models themselves.
Anyways, the GFS put out an alarming statistic for the severe weather event May 9-11.
This is the threat for severe weather at 7 am CDT May 10.
The image above defines the potential for values over 4000 j/kg CAPE values. There is a very alarming 70-80% chance of over 4000 j/kg of CAPE in Oklahoma.
We will watch this event unfolding, and be sure to turn to The Weather Centre for all your breaking severe weather.

May 7: Tornado Warning- Terre Haute, IN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
840 PM EDT SAT MAY 7 2011

INC021-153-167-080115-
/O.CON.KIND.TO.W.0028.000000T0000Z-110508T0115Z/
CLAY-SULLIVAN-VIGO-
840 PM EDT SAT MAY 7 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHEASTERN
SULLIVAN...SOUTHWESTERN CLAY AND VIGO COUNTIES UNTIL 915 PM EDT...

AT 836 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 5 MILES SOUTH OF TERRE HAUTE...MOVING SOUTHEAST AT
35 MPH. SPOTTERS ALSO RECENTLY REPORTED A ROTATING WALL CLOUD SOUTH
OF TERRE HAUTE.

IN ADDITION...AT 839 PM  HALF DOLLAR SIZE HAIL WAS REPORTED IN
TERRE HAUTE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  RILEY...PIMENTO...CORY...FARMERSBURG...HYMERA...CLAY CITY AND
  COALMONT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

Weekend Forecast: May 7-8

MAY 7
Today, we will see quite a rainy day across the Northern US. In the Ohio Valley, a storm system should move into the area around noon and continue through the afternoon.
Another storm system is out in the Northwest and will produce more precipitation. There will be spotty snow showers in higher elevations.
Despite the rain, today's temperatures will be actually nice across the entire lower 48. Most normal elevation temperatures will be at least 60 or the high 50's. The South will get the heat it deserves with a balmy 90 and above.

MAY 8
Tomorrow on Sunday, it won't be very much like a SUNday, if you know what I mean. The Northwest will continue to get battered and drenched with yet another storm system. Light showers will continue throughout the Plains into the East Coast. Even some sprinkles in the Northeast.
Again, spotty snow showers in higher elevations in the Northwest.
Even some blowing dust can be expected in Northwest Texas and Southeast Arizona.
On Sunday, temperatures will only get better, except in the Northwest. The Northwest will dip into the 60's and 50's, while the Plains could flirt with 90. The Midwest will bathe in the 70's, as will the Ohio Valley. Again, the South US will stay in the 90's, possibly into 100 in hotter locations. The Northeast should stay around 55-63 degrees.