Area Forecast Discussion
Issued by NWS Great Falls, MT

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS65 KTFX 280308
AFDTFX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
908 PM MDT SAT JUN 27 2015

.DISCUSSION...
A FEW THUNDERSTORMS DEVELOPED OER SOUTHWEST MONTANA LATE THIS
AFTERNOON. THEY REMAIN MOSTLY OVER SOUTHERN GALLATIN COUNTY. THEY
SHOULD BE DIMINISHING THIS EVENING. THE REST OF THE AREA IS UNDER
MOSTLY CLEAR CONDITIONS. FORECAST REFLECTS THESE CONDITIONS - SO
NO UPDATE PLANNED. DB

&&

.AVIATION...
UPDATED 0125Z.
VFR CONDITIONS WILL CONTINUE OVER THE REGION THROUGH THE
PERIOD. THUNDERSTORMS SOUTH OF BIG SKY WILL DIMINISH THIS
EVENING. OTHERWISE CLEAR/MOSTLY CLEAR SKIES WILL PREVAIL
THROUGH SUNDAY. DB

&&

.PREV DISCUSSION...
/ISSUED 725 PM MDT SAT JUN 27 2015/
TONIGHT THROUGH MONDAY...VERY WARM/HOT TEMPERATURES WILL CONTINUE
TO RESIDE OVER THE REGION THROUGH MONDAY...AS AN UPPER LEVEL RIDGE
OF HIGH PRESSURE RESIDES OVER THE REGION. TEMPERATURES ARE
BECOMING WARM ENOUGH OVER THE MOUNTAINS THAT A BIT OF UNSTABLE AIR
POCKETS ARE DEVELOPING...ALLOWING FOR A FEW THUNDERSTORMS TO
DEVELOP. MOST OF THE STORMS TODAY WILL BE SOUTH OF A HELENA TO
BOZEMAN LINE...AND ON SUNDAY ISOLATED STORMS ARE POSSIBLE IN THE
SOUTHWEST AND ALONG THE DIVIDE. ANY STORMS TODAY AND SUNDAY WILL
BE SHORT LIVED...AND THE MAIN THREAT WILL BE GUSTY WINDS. FOR
MONDAY...AN UPPER LEVEL DISTURBANCE WILL TRY TO PUSH INTO THE
REGION. THIS DISTURBANCE WILL TRY TO BREAK DOWN THE RIDGE AND
ALLOW FOR A BIT MORE WIDESPREAD THUNDERSTORM ACTIVITY. MOST OF THE
STORMS WILL BE OVER THE WESTERN HALF OF THE REGION. THERE WILL BE
A BIT MORE INSTABILITY...SO SOME STORMS COULD BE ON THE STRONG
SIDE...WITH THE MAIN THREAT BEING GUSTY WINDS AND HAIL. BRUSDA

MONDAY NIGHT THROUGH SATURDAY. SHORTWAVE TROF CUTTING
THROUGH THE TOP OF THE BROAD HIGH PRESSURE RIDGE WILL MOVE ACROSS
THE REGION ON MON NIGHT WITH SCATTERED THUNDERSTORMS GRADUALLY
DISSIPATING DURING THE OVERNIGHT HOURS. COOLER NORTHWEST FLOW ALOFT
SETS UP BEHIND THE TROF FOR TUES/WED GIVING A WELCOME BREAK FROM THE
RECORD HOT TEMPERATURES AS HIGHS SLIDE BACK TO UPPER 80S TO LOW 90S.
MOST OF THE REGION WILL BE DRY ON TUES/WED BUT A WEAK SECONDARY
SHORTWAVE MAY SKIRT THE US/CAN BORDER AND GENERATE A FEW SHOWERS AND
ISOLATED THUNDERSTORMS ALONG THE HILINE FROM LIBERTY COUNTY EASTWARD
ON WED EVE.  FORECAST CONFIDENCE REMAINS LOW-TO-MARGINAL FOR THE
LATTER HALF OF NEXT WEEK AS BOTH RAW AND ENSEMBLE MODELS OFFER A
RANGE OF POSSIBLE CONDITIONS, INCLUDING 15-DEGREE DIFFERENCES IN
EXPECTED HIGH TEMPS ON FRI/SAT. THE GFS MODELS IN PARTICULAR SHOW
QUITE A BIT OF VARIANCE, INCLUDING THE RAW OUTPUT NOW PUSHING A
BACKDOOR COLD FRONT (MOVING NORTHEAST TO SOUTHWEST) AND ACCOMPANYING
THUNDERSTORMS THROUGH OUR REGION THURS NIGHT INTO FRI MORNING.  ON
THE OTHER HAND, THE ECMWF SOLUTIONS HAVE BEEN MORE CONSISTENT IN
PREDICTING THEIR DRIER AND WARMER CONDITIONS, THOUGH THEY ARE STILL
ON THE HIGHEST END OF THE TEMPERATURE FORECASTS. HAVE LEANED MORE
TOWARD THE ECMWF IN THE CURRENT FORECAST GRIDS FOR THE TIME BEING,
WITH ALMOST NO MENTION OF PRECIPITATION FROM THURS TO SAT AND
COMPROMISED ON TEMPS BY RAISING THEM ONLY TO THE LOW 90S BY SAT.
WARANAUSKAS/COULSTON

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  62  99  63 101 /   0   0   0  10
CTB  56  97  59  97 /   0   0  10  10
HLN  64 101  65 103 /   0  10  10  20
BZN  53  96  52  97 /  10  10   0  20
WEY  45  86  46  89 /  10  20  10  20
DLN  56  94  57  93 /  10  10  10  20
HVR  59 101  61 102 /   0   0   0  10
LWT  60  96  62  97 /   0   0  10  10

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

WEATHER.GOV/GREATFALLS


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.