River Flood Warning 4, NWS Glasgow, MT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
948 AM MDT TUE APR 5 2011

.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH THURSDAY...
UPDATE...A FAIRLY POTENT SHORTWAVE FEATURE CONTINUES TO CROSS
NORTHEAST MONTANA THIS MORNING. BIGGEST CHANGE FOR THIS MORNINGS
UPDATE WAS TO INCREASE CHANCES FOR PRECIPITATION ACROSS THE
SOUTHWEST AS FAIRLY WIDESPREAD RAIN IS EVIDENT ON RADAR, AND IS
BEING BACKED UP BY SURFACE OBS. OTHERWISE TRENDED DOWN TEMPS
SLIGHTLY ACROSS THE AREA GIVEN EXPECTED CLOUD COVER AND COOL AIR
ADVECTION. ALSO TRENDED UP WINDS FOR THIS AFTERNOON...MAINLY
ACROSS THE SOUTH AS SOME AFTERNOON INSTABILITY SHOULD ALLOW FOR
SOME GUSTY WINDS. GILCHRIST

PREVIOUS DISCUSSION...WATER VAPOR IMAGERY AND 500 MB HEIGHT FIELD
SHOWING A SOMEWHAT AMPLIFIED AND ACTIVE WEATHER PATTERN ACROSS THE
CONUS. A POTENT UPPER LEVEL TROUGH OVER THE EASTERN CONUS
CONTINUES TO PUSH SEVERE THUNDERSTORMS AHEAD TO THE EASTERN
SEABOARD. WEAK UPPER LEVEL RIDGING IS IN PLACE OVER THE NORTHERN
ROCKIES AS TWO UPPER LOWS SPIN OVER THE NORTHEASTERN PACIFIC AND
THE EAST CENTRAL PACIFIC.

FORECAST CHALLENGES WILL FOCUS ON TIMING AND INTENSITY DETAILS WITH
THE NEXT FEW UPCOMING STORM SYSTEMS SET TO BEGIN TUESDAY AND
THURSDAY FOR NORTHEAST MONTANA.

TODAY THROUGH TONIGHT...RADAR REFLECTIVITY HAVE ALREADY BEGUN TO
INCREASE EARLY THIS MORNING ACROSS OUR SOUTHWESTERN ZONES. WITH
GOOD MODEL AGREEMENT...FEEL CONFIDENT THAT THIS WILL CONTINUE AND
SPREAD EASTWARD THROUGH THE CWA TODAY AND TONIGHT AS AN UPPER
LEVEL SHORT WAVE DISTURBANCE SLIDES ALONG THE INTERNATIONAL BORDER. A
PICTURE OF MIXED PRECIPITATION VERSUS ONLY RAIN WILL FLUCTUATE
WITH DAILY TEMPERATURES ACROSS THE AREA. OUR NORTHERN AND
NORTHEASTERN ZONES WILL SEE MORE SNOW WHILE OUR SOUTHERN AND
SOUTHWESTERN ZONES WILL SEE MOSTLY RAIN THROUGHOUT THE SHORT TERM
FORECAST PERIOD.

WEDNESDAY THROUGH WEDNESDAY NIGHT...UPPER LEVEL RIDGING WILL KEEP
CONDITIONS DRY AS A STRONG UPPER LOW CENTER DIGS OVER THE PACIFIC NORTHWEST.

THURSDAY...THE STAGE IS BEING SET FOR ANOTHER ACTIVE AND STRONG
STORM SYSTEM TO IMPACT THE NORTHERN HIGH PLAINS. THE UPPER LEVEL
LOW CENTER CONTINUES TO DIG THROUGH THE INTER-MOUNTAIN WEST AS A
LARGE SURFACE LOW PRESSURE SYSTEM DEVELOPS OVER WYOMING AND
EASTERN MONTANA. AT THIS TIME PERIOD...MODELS BEGIN TO DIVERGE
WITH PLACEMENT AND TIMING OF PRECIPITATION. TRIED TO BLEND AND
COMPROMISE FOR NOW. AS A WHOLE THE STORM WILL LIKELY AFFECT THE
AREA THROUGH THE REMAINDER OF THE WEEK. BMICKELSON

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...
MODELS AGREE THAT A LONGWAVE TROUGH WILL DIG INTO THE WESTERN
STATES LATE THIS WEEK BUT THEY DISAGREE ON THE
STRENGTH...PLACEMENT AND TIMING. THE GFS SHOWS A FASTER SOLUTION
WHERE AS THE EC DEPICTS A SLOWER-MOVING AND DEEPER TROUGH TAKING A
MORE SOUTHERN TRACK OVER THE DESERT SOUTHWEST. THIS WILL ALLOW A
LONG FETCH OF WARM MOIST AREA TO TRAVEL NORTH. THIS SYSTEM HAS THE
POTENTIAL TO PRODUCE SIGNIFICANT PRECIPITATION AMOUNTS...HOWEVER
AT THIS TIME THE MAJORITY OF THE PRECIP LOOKS TO FALL OVER CENTRAL
AND SOUTHERN PORTIONS OF MONTANA.

AN UPPER LEVEL RIDGE WILL REBOUND OVER THE WESTERN STATES BRINGING
SLIGHTLY DRIER CONDITIONS ACROSS THE AREA. TEMPERATURES WILL NOT
WARM SIGNIFICANTLY UNDER THIS PATTERN...THE RIDGE WILL BE SHORT-
LIVED AS ANOTHER TROUGH WILL PUSH THROUGH THE PACIFIC NORTHWEST
NEAR THE END OF THE FORECAST PERIOD ON WEDNESDAY. AES

&&

.AVIATION...
A COMPLEX BUT WEAK OCCLUDED FRONT SYSTEM IS SENDING WARM MOIST
AIR AND WARM FRONT IN FROM THE WEST WHILE A COLD FRONT MOVES IN
FROM THE NORTHWEST. THIS WILL PRODUCE WET AND MIXED PRECIPITATION
THIS MORNING AND MOSTLY RAIN THIS AFTERNOON AS THE UPPER SHORTWAVE
DISTURBANCE PASSES THROUGH THE AREA. EXPECT MOSTLY VFR CEILINGS
WITH OCCASIONAL MVFR. AS A SURFACE HIGH APPROACHES FROM THE WEST
AND THE SURFACE LOW MOVES EAST EXPECT WINDS TO PICK UP AS THE
STRONG WINDS ALOFT MIX TOWARD THE SURFACE...LINING UP WITH SURFACE
WINDS TO PRODUCE WESTERLY WINDS OF 15KTS TO 25 KTS. SCT

&&

.HYDROLOGY...
WARMER TEMPERATURES WILL CONTINUE THE NEXT SEVERAL DAYS WITH SNOWMELT
RUNOFF.

CREEKS WERE RUNNING HIGH IN NORTHERN MCCONE AND RICHLAND COUNTIES
BUT NO SIGNIFICANT PROBLEMS HAVE BEEN REPORTED. NORTH OF THE
MISSOURI RIVER...WATER IS ALSO BEGINNING TO FLOW IN MANY OF THE
STREAMS AND CREEKS.

A FLOOD WARNING IS IN EFFECT FOR THE BEAVER CREEK IN WESTERN
VALLEY/EASTERN PHILLIPS COUNTIES. A FLOOD WARNING IS IN EFFECT FOR
THE BIG MUDDY RIVER IN SHERIDAN COUNTY. A FLOOD WATCH REMAINS IN
EFFECT FOR AREAL AND RIVER FLOODING POSSIBILITIES IN SOUTHERN AND
CENTRAL VALLEY COUNTY THIS WEEK. THE MILK RIVER IS NOW RISING
ACROSS PHILLIPS AND VALLEY COUNTY. WITH THE RIVER NEAR FLOOD STAGE
AT GLASGOW AND NASHUA...A FLOOD WARNING WILL LIKELY BE NEEDED
WITHIN THE NEXT DAY.

PLEASE SEE THESE PRODUCTS FOR MORE INFORMATION.

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH THURSDAY AFTERNOON FOR CENTRAL AND SOUTHERN
VALLEY.

&&

WEATHER.GOV/GLASGOW

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE GLASGOW MT
1217 PM MDT TUE APR 5 2011

MTZ016>020-059-061-062-061800-
CENTRAL AND SOUTHEAST PHILLIPS-CENTRAL AND SOUTHERN VALLEY-
DANIELS-SHERIDAN-WESTERN ROOSEVELT-NORTHERN PHILLIPS-
NORTHERN VALLEY-EASTERN ROOSEVELT-
1217 PM MDT TUE APR 5 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST
MONTANA.

.DAY ONE...TODAY AND TONIGHT

FLOOD WARNINGS ARE IN EFFECT FOR BEAVER CREEK IN WESTERN VALLEY
AND EASTERN PHILLIPS COUNTIES UNTIL THURSDAY MORNING AND FOR BIG
MUDDY CREEK IN SHERIDAN COUNTY UNTIL WEDNESDAY AFTERNOON. A FLOOD WATCH IS
IN EFFECT FOR VALLEY COUNTY UNTIL THURSDAY AFTERNOON.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

SNOW MELT RUN OFF WILL CONTINUE OVER THE NEXT SEVERAL DAYS WITH
ADDITIONAL FLOODING POSSIBLE.

A STRONG SPRING STORM SYSTEM WILL AFFECT EASTERN MONTANA THURSDAY
AND FRIDAY. THE SYSTEM WILL BRING THE POSSIBILITY OF ACCUMULATING
SNOW OR WIDESPREAD RAIN TO PORTIONS OF NORTHEAST MONTANA.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

MTZ021>027-060-061800-
PETROLEUM-GARFIELD-MCCONE-RICHLAND-DAWSON-PRAIRIE-WIBAUX-
SOUTHWEST PHILLIPS-
1217 PM MDT TUE APR 5 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST
MONTANA.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A STRONG SPRING STORM SYSTEM WILL AFFECT EASTERN MONTANA THURSDAY
AND FRIDAY. THE SYSTEM WILL BRING THE POSSIBILITY OF ACCUMULATING
SNOW OR WIDESPREAD RAIN TO PORTIONS OF NORTHEAST MONTANA.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.