Severe Thunderstorm Warning 41, NWS Glasgow, MT

NORTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
244 AM MDT MON JUL 2 2001

SFC TROF LOCATED NEAR HVR...LWT AND BIL IN CENT MT AT 08Z. SHORTWAVE
CROSSING THE TROF NORTH OF BIL PRODUCING SVR THUNDERSTORMS OVER
NRN GOLDEN VALLEY AND NRN MUSSELSHELL COUNTIES DURING THE NIGHT.

MODELS SLOWER THAN EARLIER RUNS IN MOVING THIS TROF TO THE EAST AND
NOW APPEAR TO BE TAKING ALL DAY TO MOVE IT TO THE MT/DAKOTA BORDER.
THEN...THE MODELS DROP A BACK DOOR COLD FRONT SOUTH FROM CANADA INTO
NE MT TONIGHT. UPPER RIDGE AXIS RETROGRADES FROM CENT MT TO IDAHO
BETWEEN NOW AND TUE AFTN SWITCHING WEST FLOW ALOFT TO NW.

MOIST UNSTABLE AIR PRESENT ALONG SFC TROF WITH 60+ DEWPOINTS WITH
MALTA REPORTING THE HIGHEST DEW POINT AT 64 AT 07Z. THIS AIR WILL
BECOME EVEN MORE UNSTABLE TODAY WITH DAYTIME HEATING. ETA
FORECASTING CAPE OF 1000-1500 J/KG AND LI AS LOW AS -5 FOR TODAY
ALONG AND EAST OF THE SFC TROF. WHILE UPPER LEVEL SHORTWAVES ARE
FORECASTED TO STAY NORTH AND SOUTH OF GGW FORECAST AREA TODAY AS
WAVES MOVES ACROSS SRN SASK AND SRN MT TODAY...STRONG UPWARD OMEGA
FORECASTED ACROSS NE MT FOR MOST OF THE DAY TODAY. WITH A NEAR 80
DEG CONVECTIVE TEMP THAT SHOULD BE REACHED ANYWHERE THERE IS SUN
...WILL MENTION A 30 PCT CHANCE OF THUNDERSTORMS FOR ALL ZONES TODAY
AND FOR THIS EVENING IN THE EAST.

DRIER WX SHOULD PREVAIL AFTER COLD FRONT PASSES...SO WILL KEEP TUE
DRY.

WILL HAVE HIGH TEMPS CLOSE TO FWC IN THE WEST AND BETWEEN FWC AND
MAV GUIDANCE IN THE EAST. FORRESTER

EXTENDED...MODELS IN GOOD AGREEMENT. 500 MB HIGH OVER WESTERN STATES
RIDGES N IN RESPONSE TO DEEP UPPER LOW MOVG SE THRU ONTARIO WED.
WARMING EFFECTS FOR NE MT DELAYED BY CAN SFC HIGH WED. THU WARMEST
DAY WITH WARM ADVECTION AHEAD OF NEXT SHORTWAVE MOVING EAST INTO W
CAN. MODELS A LITTLE STRONGER WITH THIS SHORTWAVE...BUT MAYBE A
LITTLE FAST PER PMD. STILL...RATHER QUICK MOVING...BUT DO EXPECT
SOME SHORTLIVED CONVECTION RIGHT ALONG FRONT. VERY DRY AIR QUICKLY
PUSHES IN FROM W AFTER FROPA. CURRENT FORECAST HAS DRY THRU PERIOD
AND WILL ADD MENTION OF TSTORMS EARLY FRI...MORE IN LINE WITH
SURROUNDING ZONES. SIMONSEN

KGGW /085 056/084 049/082 056/090 058/083 052/080 057/087
      BBUUTUU  79310/8201300
KGDV /083 055/084 049/080 052/090 057/085 052/081 053/088
      BBUUTUU  79331/8201300