Hail and Damaging Winds in Montana, June 25, 2008

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
325 PM MDT WED JUN 25 2008

.SHORT TERM...VALID FOR THU AND FRI...

HYDROLOGY...NO CHANGES TO THE WARNINGS FOR THE YELLOWSTONE RIVER
NEAR LIVINGSTON OR THE CLARKS FORK RIVER NEAR BELFRY. RECEIVED
REPORTS OF MINOR FLOODING ALONG THE CLARKS FORK JUST SOUTH OF
LAUREL...LIKELY DUE TO SOME WATER BACK UP FROM WHERE THE CLARKS
FORK MERGES WITH THE YELLOWSTONE. PERSONS LIVING ALONG ALL
WATERWAYS ACROSS THE AREA SHOULD REMAIN AWARE OF THE HIGH WATER AT
THIS TIME AND REMAIN ALERT FOR FLOODING...ESPECIALLY ALONG THE
YELLOWSTONE RIVER AND CLARKS FORK OF THE YELLOWSTONE RIVER.
THE LATEST FORECASTS FOR AREA RIVERS GENERALLY SHOW A STEADY
TREND FOR THE NEXT DAY OR TWO THEN A SLOW DECREASE IN LEVELS
THROUGH NEXT WEEK.

FOR CONVECTION THIS AFTERNOON AND EVENING...SURFACE LOW HAS
DEVELOPED OVER CENTRAL WYOMING WITH GOOD SOUTHEAST MOISTURE FETCH
OVER CENTRAL ZONES. SHEAR PROFILES LOOK STRONG ENOUGH TO SUPPORT
SEVERE THUNDERSTORMS IN THESE AREAS AND THUS A WATCH HAS BEEN
ISSUED THROUGH 9 PM THIS EVENING. ONE LIMITING FACTOR IS
TEMPERATURES. HEATING HAS BEEN LIMITED BY SMOKE ALOFT BEING
FUNNELED ACROSS THE AREA FROM THE NUMEROUS NORTHERN CALIFORNIA
WILD FIRES. THIS WILL KEEP A WEAK CAP OVER THE AREA AND LIMIT THE
NUMBER OF STORMS THAT MAY DEVELOP. HOWEVER ANY THAT DO DEVELOP
WILL BE STRONG...WITH A FEW SEVERE ACROSS CENTRAL SECTIONS. MOST
LIKELY AREA FOR SEVERE STORMS WILL BE OVER BIG HORN...SHERIDAN...ROSEBUD
AND POWDER RIVER COUNTIES. CONVECTION SHOULD CONTINUE THROUGH LATE
TONIGHT AS THE UPPER WAVE CROSSES THE AREA PUSHING STORMS EAST.
WITH SOME LINGERING INTO THE EARLY MORNING HOURS IN THE FAR
EASTERN ZONES.

TOMORROW...MODELS IN A BIT OF DISAGREEMENT WITH HOW FAST THE NEXT
COLD FRONT WILL MOVE THROUGH THE AREA. GFS KICKS IT THROUGH IN THE
MIDDLE OF THE DAY BRINGING A GOOD SHOT OF DRY AIR TO THE AREA.
THIS WOULD LIMIT LATE DAY CONVECTION TO A FEW ISOLATED CELLS. THE
WRF IS SLOWER AND DEVELOPS A PRETTY GOOD CONVECTIVE COMPLEX OVER
THE SOUTHERN HALF OF THE AREA DURING THE DAY...WITH GUIDANCE
INDICATING VERY HIGH POPS TOMORROW. HARD TO PICK A WINNER GIVEN
THE CONVECTIVE INFLUENCES ON THESE MODELS RECENTLY...SO CONTINUE
TO SPLIT THE DIFFERENCE...WITH THE BEST CHANCE OF THUNDERSTORMS
AND PRECIPITATION OVER THE EASTERN THIRD OF THE FORECAST AREA.
SHOULD BE ENOUGH DYNAMICS AND INSTABILITY TO FORCE A FEW SEVERE
THUNDERSTORMS OVER CENTRAL AND EASTERN ZONES...BUT GIVEN THE
TIMING DIFFERENCES WILL HOLD OFF MENTION IN THE ZONES. HIGHS WILL
LIKELY BE INFLUENCED BY THE SMOKE ALOFT ONCE AGAIN WITH READINGS
IN THE LOW TO MID 80S.

LOWERED FRIDAY HIGHS WELL INTO THE 70S FRIDAY WITH COOL DRY
NORTHWEST FLOW ACROSS THE AREA. 850 MIX DOWN TEMPERATURES
SUGGESTIVE OF SOME AREAS WITH HIGHS RIGHT AROUND 70 DEGREES. AN
INSTABILITY SHOWER OR THUNDERSTORM IS NOT OUT OF THE QUESTION OVER
EASTERN ZONES...THE REST OF THE AREA LOOKS DRY. CHAMBERS

.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...

OVERALL THE EXTENDED LOOKS IN PRETTY SOLID SHAPE...SO WAS VERY
LITTLE IN THE WAY OF EDITS OUTSIDE OF COLLABORATION WITH
NEIGHBORING OFFICES. A STRONG RIDGE BEGINS BUILDING INTO THE
AREA SATURDAY AND APPEARS TO DOMINATE THE REGION THROUGH THE END
OF THE EXTENDED.

SATURDAY AND SUNDAY LOOK PRETTY WARM AND DRY ACROSS THE REGION.
THE SYSTEM APPEARS CONTINUES TO BECOME MUCH MORE AMPLIFIED WITH
THE LATEST RUN...LENDING TO THE RAPID WARM UP FOLLOWING THE
PREVIOUS SYSTEM. TO COUNTER THE INTENSE WARM UP...IT APPEARS THAT
THE SYSTEM IS MUCH DIRTIER WITH MONSOONAL MOISTURE BEGINNING
SUNDAY NIGHT. HOW MUCH MOISTURE IS STILL IN QUESTION. DID REDUCE
TEMPS A BIT LATER IN THE EXTENDED DOWN FROM MID 90S TO LOW
90S...PARTLY IN RESPONSE TO HIGHER MOISTURE KEEPING TEMPS LOWER
WITH MORE CLOUD COVER...ALSO TO BETTER LINE UP WITH NEIGHBORS WHO
HAD ALREADY LOWERED TEMPS. DID NOT ADJUST POPS OTHER THAN TO
SMOOTH OUT BORDER INCONSISTENCIES.

SINCE THE READ ON THE RIDGE SEEMS TO BE JUMPING AROUND QUITE A BIT
IT SEEMS PERSISTENCE WITH CONSERVATIVE CHANGES SEEM THE BEST
CHOICE UNTIL THE PROGRESSION OF THE RIDGE SOLIDIFIES A BIT MORE.
GILSTAD

&&

.AVIATION...

VFR CONDITIONS WILL PREVAIL THROUGH THURSDAY MORNING. SCATTERED
THUNDERSTORMS ARE EXPECTED...PRIMARILY EAST OF A LINE FROM
BILLINGS TO SHERIDAN...THIS AFTERNOON AND EVENING WITH A FEW
STORMS PERSISTING INTO THE OVERNIGHT HOURS. SOME STORMS MAY BE
STRONG TO SEVERE IN NATURE. LOCALIZED MVFR TO IFR CONDITIONS ARE
POSSIBLE IN AND AROUND STRONGER STORMS IN REDUCED VISIBILITIES.
GILSTAD

&&

.PRELIMINARY POINT TEMP/POPS...

    THU     FRI     SAT     SUN     MON     TUE     WED
-----------------------------------------------------------
BIL 058/081 053/077 052/088 059/092 059/091 059/091 059/089
    33/T    20/U    01/U    11/U    11/U    21/U    21/U
LVM 049/077 046/076 045/088 052/091 051/088 052/085 052/085
    23/T    20/U    01/B    12/W    21/U    21/U    21/U
HDN 058/083 054/077 051/089 058/094 058/093 059/093 059/091
    33/T    20/U    01/U    11/U    11/U    21/B    21/B
MLS 058/085 054/075 052/087 061/091 061/093 062/094 062/092
    34/T    22/T    01/U    11/U    11/U    11/U    21/U
4BQ 057/086 053/075 050/087 058/090 059/092 059/093 059/092
    34/T    32/T    01/B    11/U    11/U    21/B    21/B
BHK 054/082 051/072 048/084 058/090 058/091 059/089 059/087
    34/T    32/T    21/U    11/U    11/U    11/U    21/U
SHR 050/079 049/071 046/086 052/089 052/087 053/089 053/088
    44/T    30/B    01/B    12/W    21/B    21/B    21/B

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...SEVERE THUNDERSTORM WATCH 605 IN EFFECT UNTIL 9 PM MDT THIS
      EVENING FOR ZONES 29>32-35>39-42-56>58-63-67.
WY...SEVERE THUNDERSTORM WATCH 605 IN EFFECT UNTIL 9 PM MDT THIS
      EVENING FOR ZONES 98-99.

&&

WEATHER.GOV/BILLINGS

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE BILLINGS MT
136 PM MDT WED JUN 25 2008

MTZ028>042-056>058-063>068-WYZ098-099-261945-
SOUTHERN WHEATLAND-MUSSELSHELL-TREASURE-NORTHERN ROSEBUD-CUSTER-
FALLON-NORTHERN STILLWATER-YELLOWSTONE-POWDER RIVER-CARTER-
SOUTHERN BIG HORN-EASTERN CARBON-NORTHERN PARK-
NORTHERN SWEET GRASS-GOLDEN VALLEY-RED LODGE FOOTHILLS-
NORTHERN BIG HORN-SOUTHERN ROSEBUD-JUDITH GAP-PARADISE VALLEY-
LIVINGSTON AREA-BEARTOOTH FOOTHILLS-ABSAROKA/BEARTOOTH MOUNTAINS-
CRAZY MOUNTAINS-NORTHEAST BIG HORN MOUNTAINS-SHERIDAN FOOTHILLS-
136 PM MDT WED JUN 25 2008

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE AREA
THIS AFTERNOON AND EVENING...SOME MAY BECOME SEVERE
OVER SOUTHEAST MONTANA THIS AFTERNOON AND EVENING.

FLOOD WARNINGS REMAIN IN EFFECT FOR THE YELLOWSTONE RIVER NEAR
LIVINGSTON AND ALSO FOR THE CLARKS FORK OF THE YELLOWSTONE RIVER
NEAR BELFRY.

REFER TO THE LATEST GTFFLSBYZ BULLETINS FOR THE LATEST
INFORMATION.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A WEATHER DISTURBANCE WILL MOVE THROUGH THE REGION ON
THURSDAY...BRINGING A THREAT OF STRONG AFTERNOON AND EVENING
THUNDERSTORMS TO THE AREA.

FLOOD WARNING REMAINS IN EFFECT FOR THE YELLOWSTONE RIVER NEAR
LIVINGSTON AND ALSO FOR THE CLARKS FORK OF THE YELLOWSTONE RIVER
NEAR BELFRY.

IN ADDITION...AREA RIVERS AND STREAMS WILL REMAIN HIGH FOR THE
REMAINDER OF THE WEEK AS WARMER TEMPERATURES CONTINUE TO MELT
MOUNTAIN SNOW PACK. OTHER RIVERS AND STREAMS NEAR AREA MOUNTAINS
DO NOT APPEAR PRONE TO FLOODING AT THIS POINT...HOWEVER PERSONS
WITH INTERESTS ALONG RIVERS AND STREAMS FED BY MOUNTAIN SNOW PACK
ARE ENCOURAGED TO REMAIN AWARE OF RIVER LEVELS.

VIEW THE LATEST IN RIVER STAGES AND FORECASTS ON THE INTERNET AT
WWW.WEATHER.GOV/AHPS.

.SPOTTER INFORMATION STATEMENT...

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