Note: A severe weather area depicted in the Day 4-8 period indicates a 30% or higher probability for severe thunderstorms within 25 miles of any point.
PREDICTABILITY TOO LOW is used to indicate severe storms may be possible based on some model scenarios. However, the location or occurrence of severe storms are in doubt due to: 1) large differences in the deterministic model solutions, 2) large spread in the ensemble guidance, and/or 3) minimal run-to-run continuity.
POTENTIAL TOO LOW means the threat for a regional area of organized severe storms appears highly unlikely during the entire period (e.g. less than a 30% probability for a regional severe storm area across the CONUS through the entire Day 4-8 period).
Forecast Discussion
ZCZC SPCSWOD48 ALL
ACUS48 KWNS 120949
SPC AC 120949
DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0349 AM CST SUN FEB 12 2012
VALID 151200Z - 201200Z
...POTENTIAL TOO LOW TO DELINEATE A REGION SVR THREAT AREA...
CONSIDERABLE VARIABILITY EXISTS CONCERNING SHORT WAVE DEVELOPMENTS
WITHIN A COUPLE BRANCHES OF WESTERLIES EXPECTED TO LINGER ACROSS
NORTH AMERICA THROUGH THE MIDDLE TO LATTER PART OF NEXT WEEK. THIS
INCLUDES THE MANNER IN WHICH ONE SOUTHERN BRANCH IMPULSE LIFTS OUT
OF THE SOUTHERN PLATEAU/ROCKIES REGION...AND THROUGH AT LEAST
BROADLY CONFLUENT FLOW ON THE NORTHERN FRINGE OF SUBTROPICAL RIDGING
NOSING NORTHWARD INTO THE LOWER MISSISSIPPI VALLEY AND SOUTHEASTERN
STATES BY MID WEEK. THIS FEATURE MAY BE ACCOMPANIED BY SURFACE
CYCLOGENESIS ACROSS THE SOUTH CENTRAL PLAINS THROUGH THE OHIO
VALLEY...AND A MORE SUBSTANTIVE RETURN FLOW OF MOISTURE INTO AT
LEAST PORTIONS OF THE LOWER MISSISSIPPI VALLEY AND EASTERN GULF
STATES. CONFIDENCE IS INCREASING THAT DESTABILIZATION WILL SUPPORT
INCREASING CONVECTIVE POTENTIAL...PARTICULARLY WEDNESDAY NIGHT INTO
THURSDAY ACROSS PARTS OF LOUISIANA/MISSISSIPPI AND ALABAMA. IT IS
NOT COMPLETELY OUT OF THE QUESTION THAT THIS COULD INCLUDE POTENTIAL
FOR SUPERCELLS WITH TORNADOES. HOWEVER...WITH GUIDANCE GENERALLY
SUGGESTING THAT SURFACE CYCLOGENESIS WILL MOST LIKELY REMAIN RATHER
WEAK...THE RISK FOR A SIGNIFICANT SEVERE WEATHER EVENT STILL SEEMS
LOW...AND SEVERE PROBABILITIES ARE EXPECTED TO REMAIN BELOW THE
MINIMUM THRESHOLD /30 PERCENT DAY 3/ FOR A REGIONAL SEVERE WEATHER
THREAT AREA.
..KERR.. 02/12/2012
CLICK TO GET WUUS48 PTSD48 PRODUCT
weather.gov 
