Area Forecast Discussion
Issued by NWS Billings, MT

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FXUS65 KBYZ 241534
AFDBYZ

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BILLINGS MT
934 AM MDT FRI JUL 24 2015

.UPDATE...
CURRENT FORECAST LOOK ON TRACK. MODELS CONTINUE TO SHOWER WINDS
INCREASING THIS AFTERNOON...SO THE AFTERNOON CONTINUES TO LOOK
LIKE BREEZY. NO CHANGES MADE TO THE FORECAST. REIMER

&&

.SHORT TERM...VALID FOR TDY AND SAT...

THE WEAK DISTURBANCE THAT BROUGHT THE SCATTERED SHOWERS TO THE
AREA LAST EVENING HAS EXITED THE STATE WITH JUST SOME LINGERING
ISOLATED SHOWERS CONTINUING ACROSS OUR EASTERN COUNTIES THIS
MORNING. OVERALL...A QUIET COUPLE OF DAYS ARE IN STORE AS MAINLY A
ZONAL FLOW ALOFT WILL PREVAIL OVER THE FORECAST AREA. A FEW WEAK
DISTURBANCES WILL MOVE WITHIN THE FLOW WHICH MAY TRIGGER AN
ISOLATED SHOWER OR THUNDERSTORM...MAINLY DURING THE AFTERNOON AND
EVENING TODAY AND SATURDAY. TEMPERATURES BOTH DAYS WILL BE AT OR
SLIGHTLY ABOVE NORMAL WITH READINGS IN THE UPPER 80S TO LOWER 90S
WITH THE POSSIBILITY OF A FEW MIDDLE 90S FOR THE FAVORED HOTTER
LOCATIONS. HOOLEY

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

SUNDAY SOUTHWEST FLOW ALOFT WITH TEMPERATURES ON THE RISE AHEAD OF
A UNUSUALLY DEEP DEVELOPING UPPER LEVEL LOW OVER THE PACIFIC
NORTHWEST. DOES APPEAR CAPPING SHOULD IMPACT AREAS OF SOUTHERN
MONTANA BUT NORTH OF THE MUSSELSHELL RIVER AND PORTIONS OF
SOUTHWEST MONTANA WILL SEE A WEAKER CAP AND A BETTER CHANCE FOR A
THUNDERSTORM.

MONDAY IS A SIGNIFICANT WEATHER DAY AS DEEPENING SYSTEM OVER IDAHO
BEGINS MOVING INTO WESTERN MONTANA AND FAVORABLE DYNAMICS STRONGLY
DEEPEN SURFACE LOW PRESSURE OVER EASTERN MONTANA. PATTERN
INDICATES TROPOSPHERIC FOLDING IS POSSIBLE WHICH WILL AID THE
DEEP CYCLOGENESIS PROGGED BY THE MODELS. THIS WILL RESULT IN VERY
DEEP MIXING WILL YIELD STRONG GUSTY WINDS AND HOT TEMPERATURES
WITH EVENTUALLY SOME CONVECTION OVER THE WESTERN ZONES BUT WOULD
SUSPECT SOME CAPPING OVER EASTERN PORTIONS OF THE FORECAST AREA.
EXACT POSITIONING OF SUCH AN INTENSE SURFACE LOW LEADS TO SOME
DETAIL ISSUES BUT BOTH MODELS STRONGLY SUPPORT THIS SCENARIO AND
MONDAY LOOKS LIKE A FIRE WEATHER CONCERN DAY. TUESDAY IN A WELL
MIXED POST FRONTAL ENVIRONMENT ALSO LOOKS LIKE A CRITICAL FIRE
WEATHER DAY BUT CLOUD COVER AND COOLER TEMPERATURES MAY BE A
MITIGATING FACTOR.

ORIGINALLY LOOKED AT CIPS ANALOGS FOR PRECIPITATION COMPARISONS
FOR BOTH MONDAY AND TUESDAY BUT GUIDANCE HAS SWITCHED TO HIGHLIGHT
SOME WINDY DAYS LIKE AUGUST 23 2004 AND JULY 14 2009. AVERAGE WIND
SPEED IN THE 2009 CASE WAS 16.4 MPH FOR THE DAY AND 15.8 MPH FOR
THE 2004 CASE. BACK TO BACK DAYS IN JULY WITH AVERAGE WIND SPEED
FOR THE DAY OF 14 MPH OR GREATER HAS NOT BEEN DONE SINCE 2009 AND
FOR THE WINDOW OF JULY 15 TO AUGUST 7TH NOT SINCE 1999. BOTTOM
LINE...UNUSUALLY WINDY START TO NEXT WEEK SHOULD BE EXPECTED.

AFTER MONDAY TUESDAY WEATHER CALMS CONSIDERABLY AS ZONAL FLOW
BRINGS SEASONABLE TEMPERATURES AND DRY CONDITIONS. BORSUM
&&

.AVIATION...

VFR CONDITIONS ARE EXPECTED TODAY. A FEW THUNDERSTORMS WILL
DEVELOP OVER THE MOUNTAINS AND SPREAD OUT ONTO THE PLAINS. THESE
STORMS COULD CONTAIN WIND GUSTS TO 40 MPH. TWH

&&

.PRELIMINARY POINT TEMP/POPS...

    TDY SAT     SUN     MON     TUE     WED     THU
-------------------------------------------------------
BIL 090 061/091 061/091 060/082 054/076 055/085 058/089
    2/T 22/T    11/B    22/T    21/N    11/U    11/U
LVM 087 054/088 053/087 053/073 048/074 049/083 052/087
    2/T 22/T    12/T    24/T    41/N    11/U    11/U
HDN 091 058/093 060/094 059/087 053/078 054/087 056/091
    2/T 22/T    11/B    22/T    21/N    11/U    11/U
MLS 092 063/095 064/094 064/091 057/076 056/087 059/092
    1/U 12/T    11/B    22/T    21/N    11/U    10/U
4BQ 091 061/092 063/095 064/094 055/077 055/086 058/091
    2/T 22/T    11/B    22/T    21/N    11/U    11/U
BHK 090 060/091 060/092 062/092 056/076 054/083 056/088
    1/U 22/T    21/B    23/T    32/T    11/U    10/U
SHR 089 056/090 056/092 057/086 051/074 050/083 054/088
    2/T 32/T    11/U    22/T    21/N    11/U    10/U

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.

&&

$$
WEATHER.GOV/BILLINGS



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