High Wind in Montana, March 14, 2011

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
1008 AM MDT MON MAR 14 2011

.UPDATE...
FORECAST SEEMS TO BE IN PRETTY GOOD SHAPE. A WEATHER DISTURBANCE
WILL BE MOVING INTO SOUTHWEST MONTANA THIS AFTERNOON OR EARLY
EVENING. APPEARS TO BE DECENT LIFT AND MOISTURE WITH IT AND THERE
COULD BE SOME WEAK INSTABILITY. INHERITED HIGH POPS FOR THAT AREA
LOOK FINE. OVER THE PLAINS RELATIVELY STRONG DOWNSLOPE FLOW SHOULD
KEEP THE AREA GENERALLY DRY. THE PATTERN DOES NOT LOOK
PARTICULARLY FAVORABLE FOR HIGH WINDS IN THE HIGH WIND WARNING
AREA. ON THE OTHER HAND DO NOT HAVE ENOUGH CONFIDENCE THAT THEY
WON'T OCCUR TO DROP THE WARNING. DID INCREASE WINDS OVER THE
PLAINS THIS AFTERNOON SLIGHTLY. ALSO MADE SOME ADJUSTMENTS TO SKY
COVER BASED ON CURRENT SATELLITE IMAGERY AND EXPECTED TRENDS. BLANK

&&

.AVIATION...
UPDATED 0430Z.
A BROAD UPPER LEVEL TROUGH STRETCHING FROM THE PACNW COAST TO
WESTERN MT WILL CONTINUE TO BRING WIDESPREAD MID/HIGH LEVEL CLOUDS
OVER CENTRAL AND SOUTHWEST MT TONIGHT INTO MON MORNING.  BULK OF
THIS SYSTEMS PRECIPITATION IS STILL IN ID/WA/OR SO WILL LIKELY NOT
BE UNTIL MID-MORNING BEFORE WE SEE PRECIP EAST OF THE DIVIDE.  MOST
OF EXPECTED LIGHT RAIN WILL OCCUR ACROSS SOUTHWEST MT WITH CENTRAL
AND NORTH CENTRAL TERMINALS REMAINING DRY. CONDITIONS SHOULD REMAIN
VFR AT ALL TERMINALS TONIGHT WITH SOME INTERMITTENT MVFR POSSIBLE
VCNTY KHLN/KBZN TOMORROW MORNING AS PRECIP ARRIVES.  WINDS EXPECTED
TO INCREASE AS THE TROUGH APPROACHES THEN MOVES ACROSS REGION ON
MON.  GUSTS OF 25 TO 40 KTS WILL BE POSSIBLE AT ALL TERMINALS.
WARANAUSKAS

&&

.HYDROLOGY...
WARM TEMPERATURES OVER THE LAST FEW DAYS HAVE CAUSED SIGNIFICANT
SNOWMELT ACROSS THE AREA. AREAS OF RURAL FLOODING HAVE DEVELOPED
ACROSS NORTH CENTRAL MONTANA. MODERATE TEMPERATURES WILL CONTINUE
THROUGH THE WEEK WITH HIGHS AND LOWS GENERALLY ABOVE NORMALS.

&&

.PREV DISCUSSION...
/ISSUED 339 AM MDT MON MAR 14 2011/

TODAY THROUGH WEDNESDAY...AN UPPER LEVEL HIGH PRESSURE RIDGE WILL BE
EAST OF THE ZONES THIS MORNING AND HEIGHTS ALOFT WILL BE FALLING.
MOISTURE AHEAD OF A LOW PRESSURE TROF OVER THE PACIFIC NORTHWEST
WILL KEEP THE CWA UNDER MOSTLY CLOUDY SKIES. THE TROF WILL APPROACH
THE ROCKIES BY MID DAY AND BE OVER THE CWA BY LATE AFTERNOON. THE
STRONG FLOW ALOFT WILL CONTINUE INTO MONDAY EVENING. HEIGHTS ALOFT
WILL RISE OVERNIGHT AND ANOTHER HIGH PRESSURE RIDGE WILL BE OVER THE
ZONES TUESDAY. ALTHOUGH THE AIRMASS WILL COOL SLIGHTLY TODAY BEHIND
THE TROF...IT WILL WARM UNDER THE RIDGE AND TEMPS WILL RECOVER
SOMEWHAT BY TUESDAY. THIS RIDGE MOVES EAST TUESDAY EVENING AND A
UPPER LEVEL JET WILL MOVE ACROSS NORTHERN CALIFORNIA AND APPROACH
THE SOUTHWEST ZONES. THE CORE OF THIS JET WILL REMAIN OVER SOUTHERN
IDAHO AND KEEP MUCH OF SOUTHWEST MONTANA UNDERNEATH UNSETTLED FLOW
ALOFT.  A SHORTWAVE MOVING THROUGH THE SOUTHWEST FLOW ALOFT WILL
KEEP PRECIP LIKELY ACROSS THE SOUTHWEST...A CHANCE TO THE NORTH.
ZELZER

WEDNESDAY NIGHT THROUGH MONDAY...A GRADUAL AMPLIFICATION OF THE
UPPER LEVEL PATTERN IS EXPECTED LATE THIS WEEK THROUGH THIS WEEKEND
AS AN UPPER LEVEL TROUGH BECOMES ESTABLISHED ALONG THE WEST COAST.
SOMEWHAT MOIST SW FLOW ALOFT WITH WEAK EMBEDDED ENERGY WILL BRING
MAINLY MTN SHOWERS WEDNESDAY NIGHT THROUGH THURSDAY NIGHT WITH
RIDGING DEVELOPING BY FRIDAY OVER THE REGION IN RESPONSE TO THE
TROUGH AMPLIFICATION UPSTREAM ALONG THE WEST COAST. MEDIUM RANGE
MODELS APPEAR TO BE COMING INTO SOMEWHAT BETTER AGREEMENT WITH THE
DETAILS THIS WEEKEND...INDICATING A PORTION OF THE TROUGH CLOSING
OFF AND DROPPING SOUTH ALONG THE COAST WHILE ANOTHER LOBE OF ENERGY
EJECTS OUT AND ACROSS THE NORTHERN ROCKIES AND MT DURING THE LATE
SATURDAY/SUNDAY TIME PERIOD BEFORE THE ENTIRE TROUGH BROADENS AND
SHIFTS INLAND SUNDAY NIGHT INTO MONDAY. A TRANSITION TO A COOLER AND
WETTER REGIME IS FAIRLY CERTAIN WITH THE BEST CHANCE FOR WIDESPREAD
PRECIPITATION ACROSS THE AREA LOOKING TO BE LATE SATURDAY THROUGH
SUNDAY MORNING...HOWEVER TIMING DIFFERENCES STILL EXIST AMONG THE
MODELS. TEMPERATURES BEGIN AT SLIGHTLY ABOVE SEASONAL NORMS AND
GRADUALLY COOL TO SLIGHTLY BELOW AVERAGE AS THE UPPER LEVEL TROUGH
APPROACHES THE REGION THIS WEEKEND. COLD AIR DOES APPEAR SOMEWHAT
LIMITED AT THIS TIME... HOWEVER SNOW LEVELS LOOK TO LOWER TO NEAR
THE VALLEY FLOORS AND PLAINS BY SATURDAY NIGHT. HOENISCH

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  51  29  53  35 /  10  10  10  30
CTB  47  28  47  33 /  10  10  10  20
HLN  52  29  55  36 /  40  20  20  70
BZN  50  28  52  33 /  60  20  20  70
WEY  37  19  38  27 /  90  60  60  80
DLN  49  28  50  35 /  50  20  30  80
HVR  47  24  42  28 /  10  10  10  30
LWT  47  31  51  36 /  20  10  10  20

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL MIDNIGHT MDT TONIGHT EASTERN GLACIER...
NORTHERN ROCKY MOUNTAIN FRONT...SOUTHERN ROCKY MOUNTAIN FRONT.

SMALL STREAM FLOOD WARNINGS FOR SELECTED AREAS OF CASCADE AND
PONDERA AND TETON COUNTIES CONTINUE IN EFFECT.

SMALL STREAM FLOOD ADVISORY FOR SELECTED AREAS OF FERGUS AND
CHOUTEAU AND JUDITH BASIN COUNTIES CONTINUE IN EFFECT.

&&

SHORT TERM...BLANK
LONG TERM...COULSTON
AVIATION...COULSTON

WEATHER.GOV/GREATFALLS

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE GREAT FALLS MT
917 AM MDT MON MAR 14 2011

MTZ009-010-012-046-048-049-151400-
NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-CASCADE-
EASTERN PONDERA-SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON-
917 AM MDT MON MAR 14 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA
AND NORTH CENTRAL MONTANA.

.DAY ONE...TODAY AND TONIGHT

A HIGH WIND WARNING IS IN EFFECT FOR THE ROCKY MOUNTAIN FRONT AND
EASTERN GLACIER COUNTY THROUGH MIDNIGHT MDT TONIGHT.

A FLOOD WARNING FOR SMALL STREAMS IS IN EFFECT FOR PORTIONS OF
PONDERA...TETON...AND CASCADE COUNTIES THROUGH EARLY THIS WEEK.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO RELAY SIGNIFICANT WEATHER
REPORTS AND IMPACTS TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN GREAT FALLS.

MTZ013-050-051-151400-
CHOUTEAU-JUDITH BASIN-FERGUS-
917 AM MDT MON MAR 14 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA
AND NORTH CENTRAL MONTANA.

.DAY ONE...TODAY AND TONIGHT

A FLOOD ADVISORY FOR SMALL STREAMS IS IN EFFECT THROUGH THIS
AFTERNOON FOR PORTIONS OF CHOUTEAU...JUDITH BASIN...AND FERGUS
COUNTIES.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO RELAY SIGNIFICANT WEATHER
REPORTS AND IMPACTS TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN GREAT FALLS.

MTZ008-011-014-015-044-045-047-052>055-151400-
BEAVERHEAD-HILL-CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-
TOOLE-LIBERTY-BLAINE-JEFFERSON-BROADWATER-MEAGHER-GALLATIN-
917 AM MDT MON MAR 14 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
MONTANA AND SOUTHWEST MONTANA.

.DAY ONE...TODAY AND TONIGHT

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.