Weather Blog

Chilly April? Could be worse...

Chilly April? Could be worse...
An emergency worker, right, and others look over damage in Garland County near Hot Springs, Ark, Tuesday, April 26, 2011 after a confirmed tornado hit the area on Monday. (AP Photo/The Sentinel-Record, Richard Rasmussen)

I suppose as Seattle deals with what will go down as the coldest April on record and likely one of the coldest springs overall, a little rain and wind here and there isn't so bad compared to what other parts of the nation are dealing with.

The southeast, which has already been decimated by severe storms, is about to undergo another round Wednesday and Thursday.  Take a look at this very ominous and alarming forecast discussion written by a forecaster in the Jackson, Mississippi office at 10:30 a.m. CDT Wednesday: (Slightly edited to remove some non-essential text. "CWA" means "County Warning Area" -- or basically the area under their forecast jurisdiction.)

...SIGNIFICANT SEVERE STORMS AND TORNADO OUTBREAK EXPECTED THIS AFTERNOON...

A VOLATILE SITUATION IS DEVELOPING WHICH LOOKS TO SUPPORT SEVERAL SUPERCELL STORMS MOVING ACROSS THE CWA FROM LATE MORNING AND DURING THE AFTERNOON. THE COMBINATION OF INSTABILITY AND LOW LEVEL SHEAR IS OFF THE CHART AND AT LEVELS RARELY SEEN. EFFECTIVE SRH VALUES ARE CURRENTLY 600-900 M2/S2 AND FORECAST TO REMAIN VERY HIGH AND WILL LIKELY HOLD IN THE 300-600 M2/S2 RANGE IF NOT HIGHER.

INSTABILITY WILL BE QUITE HIGH AS WELL AND EXCEED 2500-3000 J/KG IF DEWPTS HOLD AROUND 70. FORCING WILL BE INTENSE AND THERE WILL BE SOME CAPPING MOVING IN FROM THE SW. THIS SHOULD KEEP CELLS DISCRETE AND SUPERCELLULAR TODAY. DEEP LAYER SHEAR IS PUSHING 80 KTS AND COULD GET HIGHER AS A 100KT MID LEVEL JET CORE PUNCHES INTO THE REGION IN A FEW HRS.

EVOLVING SUPERCELLS IS THIS EXTREME ENVIRONMENT IS BAD NEWS. THERE WILL LIKELY BE SEVERAL STRONG TORNADOES WITH A VIOLENT TORNADO POSSIBLE. CURRENT SIGTOR PARAMETERS (10-12) AND 0-1KM EHI VALUES (9-12) ARE EXTREME ABOUT AS CLASSIC AND SIGNIFICANT OF A SETUP AS THEY COME. STORMS WILL MOVE QUICKLY NE IN THE FAST DEEP LAYER FLOW AND STORMS SHOULD AVG 50-60 MPH.

THIS SETUP WILL ALSO SUPPORT LONG LIVED SUPERCELLS AND LONG TRACKED TORNADOES. I CAN`T STRESS ENOUGH HOW DANGEROUS A SITUATION THIS APPEARS. OUR SAVING GRACE WOULD BE IF STORM MODE SOME HOW BECOMES MORE LINEAR...BUT ALL HI-RES GUID SUPPORTS DISCRETE CELLS. IN ADDITION TO TORNADOES...VERY LARGE HAIL WILL BE POSSIBLE ALONG WITH DMG WINDS OF 60-80 MPH.


This kind of warning reminds me of the very ominous -- and prophetic -- warning issued by the National Weather Service in New Orleans on the eve of Hurricane Katrina. (Read that warning here, issued Aug. 28, 2005.)

While we didn't choose our cold April, the relentless severe storms back east are connected to the cold spring here. Because the problem is, spring -- nay, summer for some -- *has* arrived for the rest of the nation. Some parts of Texas are well into triple digits -- Laredo hit 111 earlier this week.

Severe storms thrive when you have a large temperature difference, and when these ultra-chilly storms pass through here and head east into the nation's mid-section, they're interacting with the "summer" heat in the south and Gulf of Mexico and you have a textbook set up for these incredible storms that some might even classify as historic. A tornado outbreak in North Carolina last week set the record for most tornadoes in a day since 1984.

And the storms rolling through Mississippi today are heading east and the East Coast will get their next round of severe weather Thursday. Meanwhile, another very cold storm is about to make its way through the Northwest on Thursday and that will eventually trigger more severe storms once it makes its way into the Midwest and east again.

So maybe a persistent chilly rain isn't so bad? At least it won't blow your roof off.