Severe Thunderstorm Warning 212, NWS Grand Forks, ND

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
224 PM CDT WED AUG 14 2002

FORECAST CHALLENGE WILL BE CONVECTIVE CHANCE AND TEMPS

.OVERVIEW...
MAIN SFC LOW MOVING EAST OF LAKE WINNIPEG...WITH COLD FRONT
EXTENDING SOUTHWEST TO ANOTHER WAVE OF LOW PRESSURE DEVELOPING WEST
OF ABR. A FEW 60 DEWPOINTS TRYING TO ADVECT NORTH INTO FAR SOUTHEAST
ZONES...WITH PLENTY OF MID CLOUDS/SHOWERS MOVING AHEAD OF SFC FRONT.
MODELS AGAIN AT ODDS THROUGH MOST OF FORECAST...AND WILL LEAN
TOWARDS ETA TODAY AS IT INITIALIZED A BIT BETTER OVERALL.

.SHORT TERM...
COLD FRONT MOVES FROM WEST TO EAST ACROSS REGION OVERNIGHT...AS
POTENT 500MB SHORTWAVE PASSED THROUGH AREA. WITH FOCUS ALONG COLD
FRONT THIS EVENING...ALONG WITH STRONG DEEP LAYER SHEAR AND IDEAL
WET BULB ZERO LEVELS AROUND 9000 FEET...EXPECT SCATTERED
THUNDERSTORMS ACROSS MOST OF REGION...WITH SHOWERS EXPECTED IN DVL
AREA BEHIND FRONT. A FEW ISOLATED STORMS HAVE POTENTIAL TO BECOME SEVERE
WITH MAIN THREAT STRONG WIND/HAIL NEAR STRONG CELLS. BEST SEVERE
THREAT WILL BE IN EASTER ZONES...IF INSOLATION CAN BOOST TEMPS
LATER THIS AFTERNOON. EXPECT OVERNIGHT LOWS GENERALLY IN UPPER 50S
WITH RESIDUAL MOISTURE AND PLENTY OF CLOUDS AROUND.

.LONG TERM...
PLENTY OF 850-700MB MOISTURE WILL LINGER ACROSS NORTHERN 2/3 OF
REGION THURSDAY...AS CONVECTIVE TEMPS NEAR 70 WILL MEAN SCATTERED
AFTERNOON SHOWERS NORTH OF US HIGHWAY 2. SLIGHTLY DRIER AIR FILTERS
INTO REGION THU NIGHT INTO FRIDAY MORNING. BY FRIDAY
AFTERNOON...WARMFRONT APPROACHING FROM SOUTH MAY PROVIDE FOCUS FOR
AFTERNOON ELEVATED THUNDERSTORMS WITH TEMPS REMAINING IN LOW/MID 70S
WITH INCREASING CLOUDS BY AFTERNOON. THREAT FOR THUNDER WILL PERSIST
FRIDAY NIGHT AS PARENT LOW MOVES THROUGH CENTRAL MN...BEFORE EXITING
NORTHEAST INTO CANADA BY SATURDAY. WILL REMOVE PRECIPITATION MENTION
ON SATURDAY WITH PROGRESSIVE NATURE OF SYSTEM...WITH TEMPS
CONTINUING BELOW NORMAL.

.EXTENDED...
MAIN CORE OF UPPER LEVEL WESTERLIES WILL CONTINUE TO BE FAIRLY FAR
SOUTH FOR THE MIDDLE OF AUGUST. THIS SHOULD TRANSLATE TO PROGRESSIVE
LONGWAVE PATTERN OVER CONUS THROUGH PERIOD WITH NEW 12Z AVN PACKAGE
FURTHER SUPPORTING IDEA I.E. FASTER SOLUTION THAN MRF. APPEARS BEST
CONVECTIVE THREAT ATTM SHOULD OCCUR DURING LATE MONDAY/TUESDAY TIME
FRAME. WEST TO NORTHWEST UPPER LEVEL TRAJECTORY SUGGESTS AIRMASS
SOURCE FOR AREA SHOULD BE MAINLY FROM CANADA WITH BELOW NORMAL
TEMPERATURE READINGS PREVAILING THROUGH PERIOD.

.FGF...NONE.
KELLENBENZ/BERG