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mt discuss

Office: TFX

FXUS65 KTFX 170223

Area Forecast Discussion
National Weather Service Great Falls MT
823 PM MDT Tue Aug 16 2022


Satellite imagery this evening shows cumulus that formed this
afternoon across eastern portions of the forecast area dissipating
while an isolated thunderstorm in the southern Gallatin range
drifts east into NW WY. Some scattered high clouds are moving into
N-central MT from the west in association with an upper level
disturbance moving across central AB. Forecast remains on track
with no significant updates this evening. Hoenisch



Much of the upcoming week will remain warm and largely dry. Better
chances for showers and perhaps a few thunderstorms arrive Friday
into the weekend across Southwest and Central Montana.


517 PM MDT Tue Aug 16 2022 (17/00Z TAF period)

VFR conditions persist across the area with just a few cumulus
across far eastern portions of north-central and southwest MT
dissipating this evening while some scattered high clouds move east
across northern areas overnight. Surface winds remain light across
most areas tonight with some west to northwest winds through early
this evening across areas just east of the Continental Divide (KCTB
and KHLN). A weak frontal boundary with wind shift to the north
moves south across the area Wednesday morning with northerly winds
persisting through Wednesday afternoon. Hoenisch


/ISSUED 517 PM MDT Tue Aug 16 2022/
The remainder of today and tomorrow... To start the period, an upper
level ridge is centered over the western US. Although much of the
region is expected to stay dry today, high-resolution models are
suggesting there may be just enough instability across the West
Yellowstone area and vicinity to manage a few showers or perhaps a
thunderstorm this afternoon into the evening. The rest of the area
is expected to stay dry, with hot temperatures expected (Upper 80's
to upper 90's). As the aforementioned upper ridge builds
northwestward, a small weakness in the ridge will result in a weak
surface low developing and quickly kicking eastward tonight. This
will induce a "cold front" that will shift winds to a more northerly
direction Wednesday. I can't rule out a few elevated nocturnal
showers or thunderstorms across eastern portions of the Hi-line
tonight as the weak surface low shifts away from the region.
Temperatures will only slightly cool Wednesday, with daytime highs
expected to remain in the 80's and lower 90's for most locations.
High-resolution models once again hint at just enough instability
in the West Yellowstone area and vicinity to result in a few
showers or perhaps a thunderstorm in the afternoon Wednesday. -AM

Thursday into the weekend... Toward the latter end of the week and
into the weekend, monsoonal moisture from the south will make way
back into Southwest Montana. At this time, confidence is too low
regarding the outcome of the monsoonal moisture, but the potential
for showers and a brief thunderstorm on Thursday increases for
locations south of I-90. Isolated to scattered convective activity
may carry through Friday and over the weekend and into the beginning
of next week, limited across Southwest and Central Montana.
Otherwise, hot and dry conditions will persist through the outlook
period with predominately light and variable winds. - Pierce


GTF  56  91  57  90 /   0   0   0   0
CTB  56  85  55  86 /   0   0   0   0
HLN  60  94  59  95 /   0   0   0   0
BZN  52  93  52  92 /   0   0   0   0
WYS  39  84  41  84 /  10  20  20   0
DLN  50  89  50  89 /   0   0   0   0
HVR  58  92  58  88 /   0   0   0   0
LWT  57  89  54  84 /   0   0   0   0




Office: MSO FXUS65 KMSO 161941 AFDMSO Area Forecast Discussion National Weather Service Missoula MT 141 PM MDT Tue Aug 16 2022 .DISCUSSION...Hot and dry conditions are expected to continue through the weekend. The highest impacts will be felt in the lower valleys of north-central Idaho where overnight lows will also stay uncomfortable. For that reason a heat advisory has been issued for that location from noon Wednesday through Friday evening. For all others, temperatures will run 10 to 15 degrees above normal during the day. However, overnight lows in all but the mid- slopes of the higher terrain, will provide some relief. Thursday monsoonal moisture will slide into our area under the ridge. Lacking lift and steering winds, any resultant convection will likely be south of I-90 and in the mountains initially. This convective pattern will slowly creep north while staying in the mountains each day through Sunday. Currently it is Sunday and Monday that the models demonstrate a wider coverage of convective activity. Sunday will be the peak in available moisture, while Monday a trough may be introduced into the pattern to provide the necessary lift. && .AVIATION...A ridge will continue to dominate the weather pattern in the Northern Rockies. Expect VFR conditions with hot temperatures creating high density altitudes during the afternoons. && .MSO WATCHES/WARNINGS/ADVISORIES... MT...None. ID...Heat Advisory from noon Wednesday to 11 PM PDT Friday Lower Hells Canyon/Salmon River Region...Orofino/Grangeville Region. && $$
Office: BYZ FXUS65 KBYZ 161956 AFDBYZ Area Forecast Discussion National Weather Service Billings MT 156 PM MDT Tue Aug 16 2022 .DISCUSSION... Tonight through Wednesday night... The weak upper-level disturbance over eastern Montana has moved east of the state. All that remains is some linger cloud cover. Some clouds and and weak radar returns have started to develop over the higher terrain with diurnal heating. Overall it looks like this activity will remain over the higher terrain. This activity will not be as wet as some of the storms have been over the last week, with less of an monsoonal component. Highs will be in the low to mid 90s today. Tomorrow will be another warm day with highs again in the low to mid 90s. As a weak shortwave move around the ridge over the the area, that will push a cold front across the area starting in the west by late morning, and through the area by late afternoon. Most of the area will just see a wind shift to the north and gusts increasing to up to around 30 mph. Southeast Montana with a little later arrival time for the front, and a little more moisture through out the atmosphere, could see some shower and thunderstorm activity in the afternoon and early evening. Reimer Thursday through Tuesday... Overall the the extended will be dominated by a ridge over the Northern Rockies. This will keep the area generall dry, outside of the higher terrain where some mostly diurnally driven showers and thunderstorms will be possible most afternoons. The best chance for the lower elevations to see a slight chance for showers and thunderstorms will be early next week as a potential shortwave shifting the ridge axis a little farther to the east. This will bring some more southwesterly flow to the area from Billings and Sheridan west. Temperatures will generally remain in the the upper 80s to lower 90s for highs. By early next week, highs might start to creep towards the mid 90s. Reimer && .AVIATION... VFR conditions expected to prevail at all terminals. Isolated thunderstorms and showers over the higher terrain expected through around 03Z and may drift into adjacent plains. Locally gusty winds to 40kts and brief MVFR conditions can be expected near any convection. The confidence in impacts to any terminals is low, with the best chance around KLVM and KSHR. Reimer && .PRELIMINARY POINT TEMP/POPS... Wed Thu Fri Sat Sun Mon Tue ----------------------------------------------------------- BIL 065/095 063/088 060/085 057/088 060/090 061/089 062/086 00/U 00/U 00/U 01/U 11/U 12/W 23/W LVM 056/095 054/090 052/087 051/091 055/091 055/088 054/084 00/U 00/U 01/U 11/U 12/T 23/T 33/T HDN 062/097 059/089 055/087 054/092 055/092 057/091 058/089 01/U 10/U 00/U 00/U 01/U 11/U 22/W MLS 066/095 062/086 057/083 057/087 059/090 060/090 061/089 12/T 10/U 00/U 00/U 00/U 00/U 11/B 4BQ 066/095 062/085 056/081 055/086 058/089 059/088 060/088 02/T 10/U 00/U 00/U 00/U 01/U 12/W BHK 064/091 058/083 053/080 053/082 055/086 057/086 058/085 13/T 21/U 00/U 00/U 00/U 00/U 11/B SHR 061/095 058/088 053/084 052/088 055/089 056/089 056/087 02/T 10/U 00/U 01/U 11/U 11/U 23/T && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...None. WY...None. && $$
Office: GGW FXUS65 KGGW 161529 AFDGGW Area Forecast Discussion National Weather Service Glasgow MT 929 AM MDT Tue Aug 16 2022 .DISCUSSION... Nudged some of the forecast grids toward the latest preferred model guidance through tomorrow as thunderstorm chances increase for the NE and E zones tonight into Wednesday. Widespread severe storms are not expected but a strong storm is possible. TFJ Previous discussion... Weak boundary lingering across southern Montana continuing to produce a few thunderstorms early this morning. This convection should weaken over the next few hours, setting up another hot and dry day for northeast Montana. Shortwave pushing across southern British Colombia will dive across the northern Plains, while the upper ridge rebounds strongly over the Pacific northwest midweek. This wave will bring a cold front through the region tonight, with thunderstorms developing ahead of the front, especially across the eastern zones on Wednesday. Behind the shortwave, a highly amplified upper pattern develops with ridge over the west and trof in the east. A stronger shortwave drops into the northern plains on Thursday, shifting the central low from New England into the upper midwest. This will keep some slightly cooler air over eastern Montana into the weekend. && .AVIATION... VFR. A few thunderstorms are possible late tonight into Wednesday morning as a cold front moves across the region. While conditions are to remain VFR, gusty and/or erratic winds can be expected in the vicinity of any thunderstorm. TFJ EQUIPMENT: While the KGDV visibility sensor is down, amendments will be limited to cloud and wind for this terminal. && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$