547
FXUS65 KBYZ 071120
AFDBYZ
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BILLINGS MT
520 AM MDT WED MAY 7 2025
KEY MESSAGES
- AREAS OF FOG ARE POSSIBLE FOR MUCH OF THE REGION WEDNESDAY
MORNING, ESPECIALLY ALONG THE IMMEDIATE FOOTHILLS.
- WARM CONDITIONS WILL RETURN TODAY AND CONTINUE THROUGH THE
WEEKEND. EXPECT DIURNAL RISES ON RIVERS AND STREAMS THROUGH THE
WEEKEND.
- SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE FORECAST
THURSDAY INTO FRIDAY. THE CHANCE OF PRECIPITATION RETURNS
SUNDAY INTO EARLY NEXT WEEK.
DISCUSSION
530AM UPDATE
FOG HAS STRUGGLED TO DEVELOP ACROSS THE CWA THIS MORNING UP UNTIL
THE PAST HOUR OR SO. WEBCAMS ARE STARTING TO SHOW SOME LOCALLY
DENSE FOG, ESEPCAILLY IN THE FOOTHILLS REGIONS. BASED OFF OF THE
OBSERVATIONS ACROSS THE AREA AND TRENDS IN TEMPS, AS WELL AS WINDS
AND CLOUD COVER, THIS DENSE FOG WILL LIKELY EXPAND THROUGH
SUNRISE. AFTER SUNRISE THOUGH, EXPECT FOG TO QUICKLY ERODE AS
TEMPS SHARPLY REBOUND INTO THE LOW 60S BY NOON TODAY. THE REST OF
THE FORECAST REMAINS ON TRACK. WMR
DISCUSSION
THROUGH THURSDAY EVENING...
AREAS OF FOG ARE POSSIBLE THROUGH THIS MORNING, ESPECIALLY IN THE
FOOTHILLS AND ALONG RIVER VALLEYS. THE RECENT PRECIPITATION HAS
LEFT MUCH OF THE CWA WITH SATURATED GROUND AND HIGH RH VALUES. AS
OF THE 1AM OBSERVATION, ROUGHLY HALF OF ALL SITES ARE REPORTING RH
VALUES OF AT LEAST 80%, WITH THE HIGHEST VALUES IN THE FOOTHILLS.
ALL OF OUR METARS ARE SHOWING A THINNING/CLEARING OF THE MID-LEVEL
CLOUDS AS WELL AS WEAKENING WINDS. THIS SHOULD ALLOW FOR
RADIATIONAL COOLING TO REALLY START TO TAKE EFFECT IN THE COMING
HOURS. THE AREAS THAT DID NOT SEE MUCH IN THE WAY OF PRECIP OVER
THE PAST 48HRS (IE. MILES CITY, BAKER, ECT.) SHOULD REMAIN OUT OF
THE FOG WITH THE EXCEPTION OF THE LOWER RIVER VALLEYS SUCH AS THE
YELLOWSTONE. ALL FOG THAT DOES FORM WILL RAPIDLY DISSIPATE AFTER
SUNRISE AS TEMPS WILL RAPIDLY WARM INTO THE AFTERNOON.
AS THE RIDGE BEGINS TO DEVELOP THE NEXT FEW DAYS WILL RETURN TO
WARM TEMPS WITH WIDESPREAD HIGHS BACK IN THE 70S TODAY AND LOW 80S
POSSIBLE THURSDAY. LATER THIS AFTERNOON INTO THE EARLY EVENING,
SOME WEAK ENERGY WILL SLOWLY DRIFT FROM CENTRAL ID INTO SW MT.
THIS COULD PRODUCE SOME ISOLATED SHOWERS NEAR LIVINGSTON AND IN
THE WESTERN MOUNTAINS AS THUS SOME 15% POPS HAVE BEEN ADDED TO
THIS REGION.
A WEAK SHORTWAVE WILL PASS JUST NORTH OF THE AREA THURSDAY WHICH
COULD BRING A CHANCE FOR ISOLATED TO WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS THURSDAY AFTERNOON AND EVENING. THE STRONGEST STORM
MAY PRODUCE SOME BREEZY WINDS AND SOME SMALL HAIL, BUT OVERALL
IMPACTS APPEAR TO REMAIN MINIMAL. WMR
THURSDAY NIGHT THROUGH WEDNESDAY...
A WEAK SHORTWAVE SLIDING THROUGH THE REGION WILL BRING SHOWERS AND
WEAK THUNDERSTORMS TO THE AREA THURSDAY EVENING AND NIGHT, WITH
SHOWERS AND THUNDERSTORMS LINGERING OVER THE SOUTHERN MOUNTAINS
AND FOOTHILLS ON FRIDAY. OUTSIDE OF THE SHOWER/THUNDERSTORM
CHANCES THURSDAY/FRIDAY (15 TO 50 PERCENT CHANCE), WARM, ABOVE
NORMAL TEMPERATURES ARE FORECAST THROUGH AT LEAST MONDAY AS UPPER
LEVEL RIDGING MOVES THROUGH THE REGION. DURING THIS TIME,
TEMPERATURES ACROSS THE LOWER ELEVATIONS ARE EXPECTED TO RANGE
FROM THE 70S TO LOWER 80S FRIDAY, WARMING FURTHER INTO THE UPPER
70S AND 80S SATURDAY THROUGH MONDAY. SOME AREAS ALONG THE RIVER
VALLEYS OF EASTERN MONTANA COULD SEE 90 DEGREES OVER THE WEEKEND
INTO MONDAY (50 TO 75 PERCENT, GREATEST AROUND MILES CITY IN THE
YELLOWSTONE RIVER VALLEY). SNOW MELT IS EXPECTED TO INCREASE, WITH
TEMPERATURES WARMING INTO THE 50S AND 60S OVER THE HIGHER
TERRAIN, WITH LOW TEMPERATURES REMAINING ABOVE FREEZING. THIS
WILL BRING DIURNAL RISES TO RIVERS AND STREAMS ACROSS THE AREA,
BUT MAINLY ALONG THE FOOTHILLS. THOSE WITH PROPERTY OR RECREATION
PLANS ON WATERWAYS THIS WEEKEND SHOULD BE AWARE OF THE INCREASED
FLOWS AND VERY COLD WATER. FLOODING IS NOT EXPECTED AT THIS TIME.
PRECIPITATION CHANCES BEGIN INCREASING OVER WESTERN AREAS ON
SUNDAY AS LARGE SCALE TROUGHING MOVES INTO THE PAC NW, INTRODUCING
SW FLOW ALOFT TO THE REGION. SHOWERS AND THUNDERSTORMS ARE
POSSIBLE SUNDAY AFTERNOON AND EVENING (15 TO 50 PERCENT CHANCE)
AS MOISTURE STREAMS IN FROM THE SOUTHWEST. SOUTHWEST FLOW IS A
PATTERN THAT BRINGS THE POTENTIAL FOR STRONG THUNDERSTORMS THIS
TIME OF YEAR, SO SOMETHING TO WATCH. AS THE LARGE SCALE TROUGHING
CONTINUES TO PUSH INLAND EARLY NEXT WEEK, AN ASSOCIATED UPPER LOW
IS PROGGED TO DEVELOP SOMEWHERE OVER THE INTERIOR WEST, BRINGING A
RETURN TO COOLER AND WETTER CONDITIONS. THE TIMING, STRENGTH AND
AMOUNT OF PRECIPITATION ASSOCIATED WITH THIS SYSTEM ARE STILL VERY
UNCERTAIN, BUT THERE IS MODERATE CONFIDENCE IN COOLER CONDITIONS
AND INCREASING SHOWER AND THUNDERSTORM CHANCES EARLY NEXT WEEK.
STP
AVIATION
12Z DISCUSSION...
FG HAS STRUGGLED TO DEVELOP UP UNTIL THIS POINT ACROSS THE
FORECAST AREA. SOME ASOSS ACROSS THE REGION HAVE SEEN FG/BR THIS
MORNING AND IT HAS BEEN DENSE AT TIMES. WHEN LOOKING AT WEBCAMS
ACROSS THE AREA IT APPEARS THAT FG HAS BEGUN TO REALLY DEVELOP
ACROSS THE AREA IN THE PAST HOUR. WHATEVER FG DOES DEVELOP WILL
QUICKLY ERODE AFTER SUNRISE.
ALL SITES SHOULD BE VFR AFTER 14Z AND REMAIN SO THROUGHOUT THE
TAF PERIOD. SOME BREEZY WINDS COULD OCCUR THIS AFTERNOON WITH
GUSTS TO 25KTS POSSIBLE. THERE IS A VERY SLIGHT CHANCE THAT SOME
SHRA PASS NEAR KSHR THIS AFTERNOON, BUT CONFIDENCE REMAINS LOW
AND THUS IT WAS NOT INCLUDED IN THE TAF. WMR
PRELIMINARY POINT TEMP/POPS
TDY THU FRI SAT SUN MON TUE
-------------------------------------------------------
BIL 074 050/081 051/079 054/087 058/087 056/084 053/071
0/U 02/T 31/U 00/U 12/T 34/W 45/T
LVM 073 046/076 044/077 049/083 053/080 051/076 047/065
2/W 23/T 31/U 01/U 24/T 45/W 46/W
HDN 075 044/081 049/081 050/088 054/089 054/086 051/074
0/U 02/T 31/U 00/U 12/T 44/W 44/W
MLS 075 049/083 052/080 054/089 057/090 057/086 055/078
0/U 03/T 22/W 10/U 11/B 33/W 43/W
4BQ 071 050/081 051/078 053/085 058/088 057/085 055/079
0/U 03/T 11/U 00/U 01/U 22/W 33/W
BHK 072 047/082 048/078 051/086 055/088 054/084 052/079
0/U 02/T 21/U 10/U 00/U 21/B 32/W
SHR 071 041/077 045/076 046/083 051/085 053/082 049/074
0/U 02/T 23/T 00/U 02/T 23/W 34/T
BYZ WATCHES/WARNINGS/ADVISORIES
MT...NONE.
WY...NONE.
WEATHER.GOV/BILLINGS
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