Special Weather Statement, NWS Great Falls, MT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
932 PM MDT MON AUG 6 2012

.UPDATE...
CURRENT FORECAST WAS ON TRACK...WITH JUST MINOR ADJUSTMENTS FOR
CURRENT TRENDS. EVENING SHOWERS AND THUNDERSTORMS HAVE GENERALLY
PUSHED NORTH OF AN AUGUSTA TO LEWISTOWN LINE. THUS POPS HAVE BEEN
LOWERED SOUTH OF THAT LINE...AND RAISED A BIT IN THE CONRAD AREA
WHERE THE STORMS CURRENTLY AREA. NO SEVERE WEATHER HAS BEEN
REPORTED SO FAR THIS EVENING...JUST BRIEF HEAVY RAINFALL...AND
SOME WIND GUSTS IN THE 30-40 MPH RANGE FROM WEATHER SPOTTERS.
OVERNIGHT LOWS LOOK ON TRACK...WITH JUST A FEW MINOR TWEAKS.

THE RED FLAG WARNING HAS BEEN CANCELLED...AS HUMIDITIES HAVE
INCREASED AND THE STORMS HAVE PUSHED NORTH OF THE WARNING AREA.
THE MAIN FIRE WEATHER CONCERN OVER THE NEXT FEW DAYS WILL BE LOW
HUMIDITIES AND HOT TEMPERATURES. SEE BELOW FOR FURTHER DISCUSSION.

OTHERWISE...ALL ELSE IS ON TRACK FOR TONIGHT. BRUSDA

&&

.AVIATION...
UPDATED 0000Z.
ISOLATED THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS AFTERNOON AND
EVENING AS A WEAK UPPER-LEVEL TROUGH LIFTS NORTHWARD INTO
NORTH-CENTRAL MONTANA. HAVE KEPT VCTS AT ALL TAF SITES EXCEPT KHVR
WITH MOST OF THE ACTIVITY DEVELOPING OVER HIGHER TERRAIN. NEAR
STRONGER THUNDERSTORMS...BRIEF MVFR CONDITIONS ARE POSSIBLE
OTHERWISE VFR WILL PREVAIL THROUGH THE PERIOD. SOME GUSTY OUTFLOW
WINDS UP TO 30KTS ARE ALSO POSSIBLE WITH SHOWERS AND THUNDERSTORMS.
AS INSTABILITY WANES WITH SUNSET AND THE TROUGH MOVES OUT OF THE
AREA...THUNDERSTORMS WILL DIMINISH AND MAINLY CLEAR SKIES WITH LIGHT
WINDS ARE ANTICIPATED THROUGH THE REMAINDER OF THE NIGHT. SOME
SHOWERS MAY LINGER THROUGH MIDNIGHT AROUND KHVR SO HAVE KEPT VCSH IN
THE CURRENT TAF THROUGH MIDNIGHT. MLV

&&

.FIRE WEATHER...
UPDATED 930 PM.
IT STILL LOOKS MARGINAL FOR RED FLAG CONDITIONS TUESDAY. MINIMUM
RELATIVE HUMIDITIES WILL BE VERY LOW (GENERALLY IN THE 6 TO 12
PERCENT RANGE) BUT SUSTAINED WIND SPEEDS SHOULD NOT GET MUCH MORE
THAN 15 MPH. CONFIDENCE IN RED FLAG CONDITIONS FOR TUESDAY IS
SLIGHTLY LESS THAN 50 PERCENT WHEREAS FOR THE ISSUANCE OF A WATCH
ONE SHOULD EXPECT CONFIDENCE LEVELS ABOVE 50 PERCENT. THE MOST
FAVORED AREAS TO SEE THE BREEZY WINDS ARE THE HELENA VALLEY...AND
MUCH OF HILL AND BLAINE COUNTIES...FROM ABOUT NOON TIME UNTIL
9 PM. WE WILL CONTINUE TO EVALUATE MODEL UPDATES THROUGH THE
NIGHT ON THIS SITUATION. BLANK/BRUSDA

&&

.PREV DISCUSSION...
/ISSUED 530 PM MDT MON AUG 6 2012/
TONIGHT THROUGH WEDNESDAY...A WEATHER DISTURBANCE ALOFT WAS MOVING
THROUGH SOUTHWEST MONTANA MONDAY AFTERNOON AND WILL CONTINUE
MOVING SLOWLY NORTHEAST REACHING NORTH CENTRAL MONTANA LATE MONDAY
NIGHT. THE DISTURBANCE SHOULD THEN MOVE EAST OF THE FORECAST AREA
BY TUESDAY AFTERNOON. EXPECT ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS AHEAD OF THE FEATURE THIS EVENING THEN JUST ISOLATED
SHOWERS AND THUNDERSTORMS AHEAD OF THE FEATURE LATE TONIGHT INTO
TUESDAY. DRIER AIR WILL MOVE INTO THE AREA IN THE WAKE OF THE
DISTURBANCE. MEANWHILE A STRONG UPPER RIDGE WILL DEVELOP OVER
IDAHO AND WESTERN MONTANA TUESDAY AFTERNOON BEFORE MOVING INTO
CENTRAL MONTANA ON WEDNESDAY. THE RIDGE SHOULD KEEP THE FORECAST
AREA DRY THROUGH WEDNESDAY MORNING. FOR WEDNESDAY AFTERNOON THE
COMBINATION OF ANOTHER WEAK SURGE OF MONSOONAL MOISTURE AND WEAK
INSTABILITY COULD LEAD TO ISOLATED TO SCATTERED THUNDERSTORMS OVER
SOUTHWEST MONTANA. STILL EXPECT HOT TEMPERATURES TUESDAY AND
WEDNESDAY WITH SOME AREAS APPROACHING RECORD HIGH TEMPERATURES.
BLANK

WEDNESDAY NIGHT THROUGH MONDAY...THE LARGE SCALE UPPER LEVEL
RIDGE CENTERED OVER THE FOUR CORNERS REGION WILL CONTINUE TO
DOMINATE THE WEATHER PATTERN THROUGH THE LONG TERM PERIOD.
SOUTHWEST FLOW ALOFT WILL SLOWLY YIELD TO A MORE ZONAL PATTERN AS
A SHORTWAVE TROUGH MOVES ACROSS NORTHERN CANADA. SOME
INSTABILITIES WILL BE PRESENT AS WEAK POCKETS OF MONSOONAL
MOISTURE CONTINUES TO MOVE UP THE SPINE OF THE ROCKY MOUNTAINS.
WILL CONTINUE TO KEEP POPS SLIGHTLY LOWER THAN CLIMATOLOGICAL
AVERAGES...MAINLY DUE TO THE WEAK PRESENCE OF MONSOONAL
MOISTURE...WHILE TEMPERATURES REMAIN ABOVE SEASONAL AVERAGES DUE
TO THE STRONG RIDGE THAT IS EXPECTED TO REMAIN IN PLACE THROUGH
THE BULK OF THE EXTENDED. SUK

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  61  96  59  99 /  20  10   0  10
CTB  58  91  54  94 /  30  10   0   0
HLN  61  94  60  96 /  10  10   0  10
BZN  51  93  51  96 /  10  10   0  10
WEY  41  83  41  86 /  10  10  10  10
DLN  55  91  52  92 /  10  10   0  20
HVR  62  95  58  97 /  20  20   0  10
LWT  56  91  55  93 /  20  10   0  10

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 10 AM TO 9 PM MDT TUESDAY FOR FAR
NORTHEASTERN FERGUS COUNTY.

&&

WEATHER.GOV/GREATFALLS

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE GREAT FALLS MT
851 PM MDT MON AUG 6 2012

MTZ008>015-044>055-071200-
BEAVERHEAD-NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-HILL-
CASCADE-CHOUTEAU-CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-
TOOLE-LIBERTY-EASTERN PONDERA-BLAINE-
SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON-JUDITH BASIN-FERGUS-
JEFFERSON-BROADWATER-MEAGHER-GALLATIN-
851 PM MDT MON AUG 6 2012

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

.DAY ONE...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.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
947 PM MDT MON AUG 6 2012

MTZ044-046-070430-
EASTERN PONDERA MT-TOOLE MT-
947 PM MDT MON AUG 6 2012

...SIGNIFICANT WEATHER ADVISORY FOR EASTERN PONDERA AND SOUTHERN
TOOLE COUNTIES UNTIL 1030 PM MDT...

AT 933 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 8 MILES NORTHEAST OF CONRAD...MOVING NORTHEAST AT
30 MPH.

WIND GUSTS UP TO 45 MPH ARE EXPECTED WITH THIS STORM...ALONG WITH
HEAVY RAIN AND FREQUENT DANGEROUS LIGHTNING.

LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...MAINLY RURAL AREAS
OF EASTERN PONDERA AND SOUTHERN TOOLE COUNTIES.

IF THREATENING WEATHER APPROACHES YOUR AREA...TAKE SHELTER IN A
STURDY BUILDING.

LAT...LON 4854 11213 4839 11137 4809 11172 4823 11227
TIME...MOT...LOC 0345Z 204DEG 8KT 4827 11180

MLV