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
511
FXUS65 KGGW 060246 AAA
AFDGGW

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE GLASGOW MT
846 PM MDT THU MAY 5 2016

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

SENT AN UPDATE TONIGHT TO TRY AND PIECE TOGETHER THE CHANCES FOR
PRECIPITATION TONIGHT WITH HOURLY POPS AND WEATHER GRIDS. FOLLOWED
THE WETTER GFS AND HRRR SOLUTIONS BUT MUTED THEM SOMEWHAT.
THINKING THAT THUNDERSTORM CHANCES WILL DIE OFF AFTER MIDNIGHT.
NORTHWEST WINDS HAVE ALREADY BEGUN TO SET UP IN RESPONSE TO THE
APPROACHING COLD FRONT WHICH WILL PROBABLY BE THE FOCUS FOR SOME
SCATTERED RAIN SHOWERS OVERNIGHT AND TOMORROW MORNING. BMICKELSON

PREVIOUS SHORT TERM DISCUSSION...AS THE UPPER RIDGE DRIFTS
EASTWARD...SATELLITE IMAGERY IS SHOWING CLOUDINESS BEGINNING TO
ENTER THE AREA AS THE NORTHERN STREAM OF THE UPPER LOW TO THE
SOUTHWEST IS BEGINNING TO ENTER THE AREA. MODELS ARE FINALLY IN
FAIRLY CLOSE AGREEMENT REGARDING THE PLACEMENT AND TIMING OF THE
PRECIPITATION...BUT ARE A LITTLE LESS SO ON PRECIPITATION AMOUNTS.
WENT WITH A GENERAL CONSENSUS WITH MOST AREAS RECEIVING A FEW
HUNDREDTHS TO A COUPLE TENTHS OF AN INCH OF RAIN THROUGH FRIDAY.

WITH THE APPROACHING MOISTURE THIS EVENING...THERE IS A CHANCE OF
SHOWERS AND THUNDERSTORMS OVER OUR WESTERN ZONES TONIGHT AND INTO
EARLY FRIDAY MORNING. AFTER SUNRISE FRIDAY THE THUNDERSTORM
CHANCES DECREASE AND MAINLY LIGHT SHOWERS ARE EXPECTED.

BY FRIDAY AFTERNOON...MODEL AGREEMENT KEEPS MOST OF THE
PRECIPITATION SOUTH OF OUR AREA AS A NARROW RIDGE OF HIGH PRESSURE
MOVES THROUGH...ALTHOUGH SOME LIGHT SHOWERS COULD LINGER IN OUR
SOUTHERN ZONES INTO SATURDAY MORNING. THAT NARROW RIDGE KEEPS US
RELATIVELY DRY ON SUNDAY.


.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...

BLENDED CURRENT FORECAST WITH THE 12Z MODELS. MODELS CONTINUED TO
HAVE TROUBLE WITH RESOLVING SYSTEM EARLY NEXT WEEK WITH THE ECMWF
SHOWING MORE OF AN OPEN WAVE AND THUS FASTER. THE GFS CLOSES IT
OFF AND GIVES THE CWA MORE PRECIP THROUGH THE REMAINDER OF THE
PERIOD. TFJ

PREVIOUS DISCUSSION...
AN UPPER RIDGE WILL BE OVER THE AREA SATURDAY NIGHT WITH DRY
WEATHER. THAT RIDGE WILL MOVE TO THE EAST ON SUNDAY AND AN UPPER
TROUGH WILL MOVE IN FROM THE WEST. SUNDAY WILL REMAIN DRY AS IT
LOOKS LIKE MOISTURE WILL MOVE INTO THE AREA SUNDAY NIGHT AND
MONDAY. A COLD FRONT ASSOCIATED WITH THE SYSTEM WILL MOVE THROUGH
EASTERN MONTANA ON MONDAY. ATMOSPHERE MAY BE UNSTABLE ENOUGH FOR
THUNDERSTORMS MONDAY AFTERNOON AND EVENING. WILL MENTION A SLIGHT
CHANCE FOR NOW.

THE UPPER TROUGH AND MOISTURE WILL REMAIN OVER THE AREA ON
TUESDAY. WILL MAINTAIN A CHANCE OF SHOWERS. ATMOSPHERE MAY BE
UNSTABLE ENOUGH FOR THUNDERSTORMS. WILL MENTION A SLIGHT CHANCE.

MODELS DIFFERENCES START APPEARING TUESDAY NIGHT AND WEDNESDAY AS
GFS WANTS TO MOVE UPPER TROUGH/LOW TO THE EAST AND ECMWF KEEPS AN
UPPER LOW OVER MONTANA. WILL MAINTAIN CHANCE OF SHOWERS.

NEXT THURSDAY...GFS HAS NW FLOW ALOFT WITH SHORTWAVES WHILE THE
ECMWF MOVES THE UPPER LOW TO THE DAKOTAS. WILL CONTINUE A SLIGHT
CHANCE OF SHOWERS. FORRESTER

&&

.AVIATION...

SYNOPSIS:
A SHORTWAVE TROUGH AND COLD FRONT IS EXPECTED TONIGHT.

FLIGHT CATEGORY: VFR.

WX/WIND: ISOL TO SCT SHOWERS AND THUNDERSTORMS AND MID LEVEL
CLOUDS ARE EXPECTED TONIGHT WITH THE COLD FRONT. EXPECT LIGHT
MAINLY SOUTH TO SW WINDS TO BECOME NW TO NORTH 10 TO 20 KNOTS
AFTER 06Z TONIGHT AS THE COLD FRONT MOVES THROUGH. WINDS CONTINUE
TO TURN CLOCKWISE INTO FRIDAY. TFJ/PROTON



&&

.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.