Wildfire in Montana, August 28 to 31, 2012

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
924 AM MDT TUE AUG 28 2012

.SHORT TERM...VALID FOR TDY AND WED...

NO CHANGES NEEDED FOR THE MORNING UPDATE. BRS

.PREVIOUS DISCUSSION...
SHORT TERM MODELS ARE IN GOOD AGREEMENT WITH THE SYNOPTIC PATTERN
OVER THE REGION. THE NEXT TWO DAYS WILL BE CRITICAL FIRE WEATHER
DAYS OVER OUR FORECAST AREA. MID LEVEL FLOW WILL BACK IN RESPONSE
TO A TROUGH PUSHING INTO THE PACIFIC NORTHWEST COAST. THIS WILL
TAP SOME VERY WARM DRY AIR TO THE SOUTHWEST AND DRIVE IT INTO OUR
REGION. SUNNY SKIES AND WILL ALLOW FOR SOME MODERATE MIXING TODAY.
MIXING WILL BE EVEN GREATER ON WEDNESDAY INFLUENCED BY SUNNY SKIES
AND VERTICAL JET DYNAMICS. THE RESULT WILL BE WIDESPREAD AFTERNOON
HUMIDITIES RANGING FROM 5 TO 12 PERCENT AND NEAR RECORD
TEMPERATURES. AS THE TROUGH EJECTS TO THE NORTHEAST ACROSS THE
MONTANA/CANADIAN BORDER IT WILL DRAG A FRONT THROUGH THE FORECAST
AREA LATE WEDNESDAY/WEDNESDAY EVENING. BRISK TO STRONG WESTERLY
WINDS ARE EXPECTED OVER THE AREA AHEAD OF THE FRONT...TURNING TO
THE NORTH BEHIND THE FRONT. BASED ON 700MB WINDS AND POST FRONTAL
PRESSURE RISES I EXPECT FRONTAL PASSAGE TO USHER IN WIND GUSTS
BETWEEN 40 AND 45 MPH FOR AN HOUR OR TWO IN MANY AREAS.

SINCE CONFIDENCE IS FAIRLY HIGH AT THIS POINT...WILL UPGRADE FIRE
WEATHER WATCH TO RED FLAG FROM NOON TODAY THROUGH MIDNIGHT WEDNESDAY
EVENING. BT

.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...

MODELS WERE DEPICTING A SOMEWHAT DIFFERENT EXTENDED PATTERN
TONIGHT AS COMPARED TO LAST NIGHT. MADE SOME FORECAST ADJUSTMENTS
ACCORDINGLY. MONSOONAL MOISTURE WILL STILL MOVE PERIODICALLY INTO
THE AREA. HOWEVER...SW FLOW WILL SET UP DURING THE PERIOD
BRINGING THE CHANCE OF THUNDERSTORMS TO THE REGION. THU WAS STILL
A POST-FRONTAL COLD ADVECTION DAY. A TRAILING SHORTWAVE WILL
CROSS THE AREA FROM THE SYSTEM THAT WILL AFFECT THE REGION ON WED.
MODELS SHOWED SOME QPF OVER THE SOUTHERN PART OF THE NE BIG HORNS
THU AFTERNOON AND NIGHT AS THE NORTHERN FRINGE OF MONSOONAL
MOISTURE MOVED INTO THIS AREA. THUS HAD POPS OVER THE NE BIG HORNS
AND KEPT THE REST OF THE AREA DRY. TEMPERATURES ON THU WILL BE
ABOUT 20 DEGREES LOWER THAN WED/S HIGHS.

BOTH THE ECMWF AND GFS PAINTED QPF OVER THE SE ZONES AND MOUNTAINS
ON FRI DUE TO SHORTWAVE ENERGY AND MONSOONAL MOISTURE AFFECTING
THE AREA. ADDED LOW POPS TO THE SE AND WENT WITH CHANCE POPS OVER
THE SOUTHERN MOUNTAINS. RAISED HIGH TEMPERATURES ON FRI DUE TO A
WARMER 850 MB AIRMASS. SOUTHWEST FLOW AND SHORTWAVE ENERGY WILL
INCREASE OVER THE REGION FRI NIGHT AND SAT...THEN THE MODELS
BROUGHT A COLD FRONT THROUGH THE AREA SAT NIGHT. AVAILABLE
MOISTURE AND THE ABOVE FACTORS SUPPORTED LOW CHANCES OF
THUNDERSTORMS ACROSS THE AREA...SO HAVE ADDED POPS TO THESE
PERIODS. SAT LOOKED LIKE A WARMER DAY AHEAD OF THE FRONT SO RAISED
TEMPERATURES. A DRIER WESTERLY FLOW WILL OVERTAKE THE REGION SUN
THROUGH MON. AS A RESULT...HAVE SCALED BACK MON POPS. TEMPERATURES
WILL BE CLOSE TO NORMAL BOTH DAYS. ARTHUR
&&

.AVIATION...

VFR CONDITIONS WILL PREVAIL ACROSS THE REGION TODAY AND TONIGHT.
THE ONLY FLIGHT HAZARDS WILL BE POOR VISIBILITY CAUSED BY SMOKE
FROM ON GOING AREA FIRES. RICHMOND

&&

.PRELIMINARY POINT TEMP/POPS...

    TDY WED     THU     FRI     SAT     SUN     MON
-------------------------------------------------------
BIL 098 063/097 056/081 054/084 055/081 052/081 055/083
    0/U 01/U    10/U    01/U    11/B    11/U    02/T
LVM 094 054/096 046/076 044/083 044/078 044/079 046/081
    0/U 11/N    10/U    11/U    11/B    11/U    12/T
HDN 102 061/101 056/083 055/088 054/085 052/085 056/087
    0/G 01/G    10/U    00/U    10/U    01/U    02/T
MLS 101 067/100 059/084 057/087 057/083 052/079 058/084
    1/G 01/U    10/U    11/U    10/U    11/U    01/B
4BQ 100 064/099 057/084 057/088 057/085 053/084 059/083
    0/U 01/U    10/U    11/U    11/N    11/U    02/T
BHK 100 068/100 063/082 056/083 061/082 053/083 057/081
    1/U 01/U    20/U    11/U    11/B    11/U    01/B
SHR 096 060/095 052/077 053/085 051/081 049/080 052/081
    0/U 01/B    10/U    00/U    11/B    11/U    02/T

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...RED FLAG WARNING IN EFFECT UNTIL MIDNIGHT MDT WEDNESDAY NIGHT
      FOR ZONES 123>133.
WY...RED FLAG WARNING IN EFFECT UNTIL MIDNIGHT MDT WEDNESDAY NIGHT
      FOR ZONES 274-284.

&&

WEATHER.GOV/BILLINGS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BILLINGS MT
422 AM MDT TUE AUG 28 2012

MTZ028>042-056>058-063>068-WYZ098-099-291030-
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-
422 AM MDT TUE AUG 28 2012

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

.DAY ONE...TODAY AND TONIGHT

CRITICAL FIRE WEATHER CONDITIONS WILL OCCUR TODAY OVER MUCH OF
THE REGION. NEAR RECORD TEMPERATURES AND VERY LOW HUMIDITIES ARE
EXPECTED AND THIS HAS PROMPTED A RED FLAG WARNING FOR MUCH OF THE
AREA. NEW OR EXISTING FIRES COULD GROW AND SPREAD RAPIDLY TODAY.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

CRITICAL FIRE WEATHER CONDITIONS WILL CONTINUE WEDNESDAY. IN
ADDITION TO NEAR RECORD TEMPERATURES AND VERY LOW HUMIDITY...WEST
WINDS WILL INCREASE TO BETWEEN 15 AND 30 MPH. THIS CAN LEAD TO
EXPLOSIVE GROWTH AND RAPID SPREADING OF FIRES. THE RED FLAG
WARNING WILL CONTINUE FOR MUCH OF THE AREA THROUGH WEDNESDAY
EVENING. PLEASE FOLLOW YOUR LOCAL FIRE RESTRICTIONS CAREFULLY.

.SPOTTER INFORMATION STATEMENT...

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