487 
FXUS65 KGGW 072035
AFDGGW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
235 PM MDT THU AUG 7 2014

.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SATURDAY...
UPPER RIDGING WILL DOMINATE TONIGHT...MAKING FOR MAINLY DRY
CONDITIONS ACROSS MOST OF NORTHEAST MONTANA. WITH THAT SAID...CAN
NOT TOTALLY RULE OUT AN ISOLATED NOCTURNAL THUNDERSTORM ACROSS THE
FAR NORTHEAST AS A WEAK DISTRUBANCE COUPLES WITH MIDLEVEL
INSTABILITY.

FRIDAY AN UPPER TROUGH WILL PUSH INTO THE NORTHERN ROCKIES...WITH
WARM AIR ADVECTION IN A SOUTHERLY SURFACE FLOW INCREASING ACROSS
NORTHEAST MONTANA. BY THE AFTERNOON THE UPPER TROUGH WILL CAUSE
ENOUGH ASCENT IN THE UNSTABLE ENVIRONMENT OVER NORTHEAST MONTANA
FOR ISOLATED THUNDERSTORM DEVELOPMENT ACROSS THE NORTH AND WEST.

FRIDAY NIGHT THE AFOREMENTIONED TROUGH WILL PUSH INTO CENTRAL
MONTANA...CONTINUING POTENTIAL FOR SHOWERS AND THUNDERSTORMS
ACROSS THE WEST AND NORTH. 

SATURDAY THE TROUGH AND ITS ASSOCIATED SURFACE COLD FRONT WILL
PUSH THROUGH...CREATING THE CHANCES FOR THUNDERSTORMS ACROSS MUCH
OF NORTHEAST MONTANA. EXPECT GUSTY NORTHWEST WINDS TO PICK UP
BEHIND THE FRONT. AT THIS TIME TIMING OF THE FRONT WOULD LIMIT
FIRE WEATHER CONCERNS...HOWEVER THIS WILL NEED TO BE WATCHED.
GILCHRIST


.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
THE EXTENDED PERIOD REMAINS LARGELY UNCHANGED WITH GUIDANCE
CONTINUING TO DEPICT SOMEWHAT COOLER CONDITIONS BEGINNING ON
SATURDAY NIGHT AS THE CWA WILL BE IN A POST-FRONTAL ENVIRONMENT.
UPPER RIDGE WILL REBUILD ACROSS THE PACIFIC NORTHWEST ON SUNDAY
AND TRANSLATE EAST INTO EARLY NEXT WEEK. THEREFORE CONDITIONS WILL
CONTINUE TO BE GENERALLY DRY WITH A GRADUAL MODERATING TREND IN
TEMPERATURES WITH HIGHS RETURNING TO THE 90S BY TUESDAY.

MODEL DIFFERENCES CONTINUE TO GROW ADDING TO UNCERTAINTY BEYOND
EARLY NEXT WEEK. THE LATEST ECMWF SHOWS A FLATTENING OF THE RIDGE
WHILE SHORTWAVE ENERGY PUSHES ACROSS THE NORTH AND A LARGE PACIFIC
TROUGH/CLOSED LOW SETTING UP OFF THE WESTERN U.S. COAST. THIS
WOULD PROVIDE A RETURN OF PRECIPITATION CHANCES. THE GFS DOES
STILL HAVE THE TROUGH ACROSS THE WEST BUT HANDLES THE CLOSED LOW
MUCH DIFFERENTLY WHILE MAINTAINING THE UPPER RIDGE FOR A LONGER
PERIOD OF TIME ACROSS THE NORTHERN PLAINS. WILL KEEP FORECAST
SIMILAR TO PREVIOUS PACKAGE FOR MIDWEEK ONWARD ALL WHILE TRENDING
TOWARD CLIMO. MALIAWCO

PREVIOUS LONG TERM DISCUSSION...
SATURDAY NIGHT THROUGH SUNDAY NIGHT... WITH A FRONT HAVING JUST
MOVED THROUGH THE REGION SATURDAY NIGHT WILL START OFF A BIT
COOLER THAN IT HAS BEEN OVER THE LAST FEW DAYS AS FLOW TURNS
NORTHWEST THIS COOL PATTERN MAY BE ABLE TO HANG IN THROUGH SUNDAY
NIGHT. MEANWHILE TO THE WEST A MAJOR RIDGE WILL REBOUND ACROSS THE
PACIFIC NORTHWEST INTO BRITISH COLUMBIA.

MONDAY THROUGH TUESDAY... RIDGE TO THE WEST WILL TRANSITION ACROSS
MONTANA FORMING A SERIES OF CLEAR AND DRY CONDITIONS ALONG WITH
VERY WARM WEATHER IN THE MID 90S. 850 MB TEMPERATURES DURING THESE
PERIODS COULD EASILY RISE INTO THE 30*CS. IF THESE IS A BREAK IN THE
EXITING RIDGE TO SOUTHWESTERN FLOW DURING THIS PERIOD A SLIGHT
CHANCE FOR SHOWERS COULD TICK UP ON TUESDAY AFTERNOON AND EVENING. 

TUESDAY ONWARD... AT THIS POINT MODEL CONFIDENCE DROPS OFF
DRAMATICALLY WITH THE MODELS UNSURE OF WHAT TO DO WITH THE RIDGE
OVER THE THE ROCKIES OR THE TROUGH SETTING OF THE COAST OF THE
PACIFIC NORTHWEST. BEST GUESS FOR THIS TIME OF YEAR IS FOR THE
RIDGE TO SLUMP OVER INTO THE NORTHERN AND CENTRAL PLAINS AND
ALLOW THE TROUGH BY TO THE NORTH... YET SOME MODELS SUGGEST THAT
THE MOMENTUM OF THE TROUGH WILL FORCE IT DEEPER SOUTH INTO THE
INTERMOUNTAIN WEST... WHICH IS CLIMATOLOGICALLY UNLIKELY... BUT NOT OUT
OF THE QUESTION. MODERATED POP AND TEMP TRENDS TOWARDS CLIMO
DURING THESE PERIODS. GAH

&&

.AVIATION...
MAINLY VFR CONDITIONS WILL CONTINUE INTO THE OVERNIGHT ACROSS THE
TERMINALS. DO EXPECT LIGHT SOUTHERLY WINDS AT 5 TO 10 KTS THROUGH
MORNING. MALIAWCO

&&

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

&&

$$

WEATHER.GOV/GLASGOW