Area Forecast Discussion
Issued by NWS Glasgow, MT

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS65 KGGW 312031
AFDGGW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
231 PM MDT MON AUG 31 2015

.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY...

THE LONG-WAVE UPPER FLOW PATTERN ACROSS CONUS BEGINS WITH A RIDGE
IN THE EAST AND A TROUGH...CURRENTLY SPINNING OVER ALASKA AND
NORTHERN BC...PUSHING SOUTH INTO THE PACIFIC NORTHWEST. NORTHEAST
MONTANA WILL SEE A WEST-SOUTHWEST FLOW ALOFT TONIGHT. AS THE
TROUGH SETTLES FURTHER INTO THE PACIFIC NORTHWEST...LOCAL UPPER
FLOW WILL SLOWLY BACK MORE TO THE SOUTHWEST THROUGH THE REMAINDER
OF THE SHORT TERM PERIOD. THE TROUGH WILL SLOWLY NUDGE A COLD
FRONT CLOSER TO NEMONT THROUGH THE SHORT TERM...BUT NOT FULLY INTO
IT BY 00Z THURSDAY. WITH DESERT AIR CREEPING NORTH AGAIN...THIS
PATTERN WILL DRIVE TEMPERATURES BACK ABOVE NORMAL TUESDAY AND
WEDNESDAY. EXPECT TUESDAY TO SEE HIGHS 5F-10F ABOVE NORMAL AND
WEDNESDAY TO BE WARMER AT 10F-15F ABOVE NORMAL. WIND IS EXPECTED
TO BE LIGHT TO MODERATE DURING THIS PERIOD.

THE WILD CARD CHALLENGE WILL BE THE SMOKE FROM DISTANT WILD FIRES.
THE STORM SYSTEM/TROUGH THAT MOVED ACROSS THE REGION LAST NIGHT
DID A GOOD JOB OF SCOURING OUT THE SMOKE. REGIONAL AIRPORT
OBSERVATIONS SHOW TODAY 10SM EVERYWHERE. THE SKY FOR NOW IS NOT
HAZY. BUT FIRES CONTINUE IN OUR WEST. THE UPPER FLOW PATTERN
SUGGESTS MORE SMOKE COMING OUR WAY. WHETHER IT WILL REACH THE
SURFACE OR NOT IS THE CHALLENGE. ALL THAT WILL BE NEEDED IS FOR A
STAGNANT MIXING PATTERN TO TAKE HOLD EACH AFTERNOON TO BRING IT
DOWN TO THE SURFACE. FOR NOW HAVE REMOVED ALL MENTION OF SMOKE
FROM WX GRIDS.

WEDNESDAY...THE NW TROUGH WILL ENHANCE THE RIDGE OVER EASTERN
MONTANA AND LEAD TO PRE-FRONTAL WARMING IN THE AFTERNOON. THE
APPROACHING FRONTAL BOUNDARY AND WEAK SURFACE TROUGH COULD DEVELOP
ENOUGH INSTABILITY TO PRODUCE A FEW AFTERNOON SHOWERS AND THUNDER.
SCT


.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...

FORECAST CHALLENGE IN THE EXTENDED PERIOD WILL BE THURSDAY MORNING
THROUGH MONDAY MORNING. THE LARGE PACNW TROUGH WILL DEEPEN OVER
WASHINGTON AND OREGON...DIRECTING MULTIPLE PERIODS OF RAIN SHOWERS
OVER NE MONTANA...SOME OF WHICH HAVE THE POTENTIAL TO BE QUITE
HEAVY...ESPECIALLY SATURDAY NIGHT THROUGH SUNDAY. WE WILL BE FAR
ENOUGH REMOVED FROM THE WARM SECTOR OF THIS STORM SYSTEM...THAT
THUNDERSTORMS WILL BE LESS LIKELY. NOT A LOT OF INSTABILITY WILL
BE AVAILABLE.

SOME MODEL DIFFERENCES SHOW UP BY LATE SATURDAY NIGHT. THE GFS
WANTS TO QUICKLY LIFT OUT THE TROUGH AS AN OPEN WAVE ACROSS NE
MONTANA BY SUNDAY NIGHT...WHILE THE GFS WANTS TO KEEP A DEEPER
CLOSED LOW AND LIFT IT SLOWER OVER WESTERN MONTANA THROUGH MONDAY
NIGHT. THE CURRENT EC SOLUTION WOULD BE MUCH WETTER FOR US...WHILE
THE GFS SOLUTION WOULD BE DRIER. BMICKELSON

PREVIOUS LONG TERM DISCUSSION...UPPER TROF WILL BE DIGGING INTO
THE PACIFIC NORTHWEST THROUGH THE END OF THE WEEK BEFORE BEGINNING
TO LIFT EAST EARLY NEXT WEEK. A SHORTWAVE LIFTS THROUGH THE
SOUTHWEST FLOW ON THURSDAY PUSHING A COLD FRONT OUT OF EASTERN
MONTANA. THE WAVE WILL BRING MOISTURE INTO THE AREA FOR POTENTIAL
FOR SHOWERS BY FRIDAY. TEMPERATURES WILL BE COOLING AS THE UPPER
TROF SHIFTS OVER THE STATE DURING THE WEEKEND ALTHOUGH MODELS ARE
DIFFERING ON IF THE TROF WILL REMAIN OPEN OR DEVELOP INTO A CLOSED
LOW. PRECIPITATION AND COOLER TEMPERATURES WILL LINGER LONGER INTO
NEXT WEEK IF THE WAVE DOES CLOSE OFF...OTHERWISE WOULD EXPECT
WARMING AND DRYING BY THE END OF THE PERIOD. EBERT


&&

.AVIATION...

VFR...WITH BREEZY WESTERLY WINDS TODAY...BECOMING SOUTH TONIGHT.
SMOKE MAY RETURN OVERNIGHT RIDING THOSE SOUTHERLY WINDS..BUT MAYBE
NOT QUITE AS BAD AS HAS BEEN RECENTLY...AT LEAST OVER THE NEXT 24
HOURS. NO PRECIP EXPECTED FOR THIS TAF CYCLE. BMICKELSON


&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

WEATHER.GOV/GLASGOW


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.