Severe Thunderstorm Warning 30, NWS Glasgow, MT

NORTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
245 AM MDT SUN JUL 1 2001

UPPER LEVEL RIDGE AXIS WILL REMAIN OVER MONTANA INTO MONDAY AND THEN
MOVE SLOWLY WEST ON TUE. FORECAST CONCERN WILL BE THE TIMING AND
AFFECT SHORTWAVES MOVING ACROSS THE RIDGE WILL HAVE ON GGW CWA.

CURRENT WATER VAPOR LOOP SHOWS A SHORTWAVE OVER CENT MT PRODUCING A
TSTM NEAR LWT AND A WAVE ENTERING WRN MT WITH TSTMS APPROACHING
GLACIER NATL PARK.  ETA IN THE SHORT TERM DID THE BEST JOB WITH
THESE WAVES. THE CENT MT SHOULD MOVE TO SE MT THIS MORNING AND BRING
SCT PRECIP TO SRN TIER OF COUNTIES IN GGW FORECAST AREA. THE WRN MT
WAVE IS PROGGED TO MOVE ACROSS NE MT BETWEEN 13Z AND 20Z TODAY
BRINGING A BAND OF RAIN WITH IT.

AFTER THIS WAVE PASSES...A SFC TROF MOVES INTO CENT MT DURING THE
AFTERNOON AND ACROSS ERN MT TONIGHT. MODELS...ESP THE ETA BRING
UNSTABLE AIR NORTHWARD AHEAD OF THIS FRONT ON SE WINDS THIS AFTN AND
TONIGHT. WHILE THE ETA FORECAST CAPE 800 J/KG TO 1500 J/KG AND LI AS
LOW AS -5...A STRONG CAP WILL LIMIT CONVECTION UNTIL THE TROF TOUCHES
OFF ELEVATED CONVECTION TONIGHT. WILL MENTION A CHANCE OF SHOWERS
AND THUNDERSTORMS WITH THIS SFC TROF TONIGHT.

TROF EXITS THE STATE MON MORNING WITH DRIER AND WARMER AIR EXPECTED.
WILL MENTION A CHANCE OF MORNING THUNDERSTORMS EAST AS THE ETA DOES
NOT MOVE SFC TROF ACROSS MT/NO DAK BORDER UNTIL 15Z.

AS FOR TEMPS...WILL LEAN TOWARDS WARMER FWC FOR TODAY AS ALL
LOCATIONS SHOULD SEE SOME SUN TODAY.  MAV AND FWC HAVE SIMILAR TEMPS
TONIGHT AND MONDAY AND THEY LOOK REASONABLE. FORRESTER

EXTENDED...RETROGRADING PATTERNS ENDS WITH LARGE 500 MB HIGH TAKING
UP RESIDENCE OVER MOST OF WESTERN STATES...TRANSITION TO TYPICAL
MID-SUMMER PATTERN. NEW PROGS HAVE RIDGE AXIS FURTHER E WITH WEAKER
CANADIAN HIGH WED. CMC NOT IN LINE WITH OTHER MODELS AND DISCOUNTED
PER PMD. AS CAN HIGH MOVES OUT OF AREA...GOOD WARM ADVECTION PATTERN
THU AHEAD OF FRONT TRAILING THROUGH CANADA. WILL RAISE TEMPS THU.
CURRENT EXTENDED HAS DRY THROUGH PERIOD. EXPECT THERE TO BE
ISOLATED TSTORMS ALONG FRONT ABOUT THU NIGHT...BUT WILL LEAVE FOR
NEXT SET OF PROGS TO ADD ANY MENTION. SIMONSEN

KGGW /079 055/084 055/082 046/076 050/088 055/084 057/087
      TBBUUUU  79430/8211111
KGDV /078 055/085 055/082 047/076 048/088 055/083 055/086
      TBBUUUV  79443/8211111