Area Forecast Discussion
Issued by NWS Great Falls, MT
Issued by NWS Great Falls, MT
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
363 FXUS65 KTFX 230327 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 927 PM MDT Sun Sep 22 2024 .SYNOPSIS... Fairly benign conditions will be in place across the Northern Rockies through mid week. Temperatures will remain above average through at least Thursday, with Wednesday looking the warmest. Winds will be breezy at times, though do not look to be overly impactful. && .UPDATE... Tonight there will be isolated rain showers across North-central and Central Montana. Little to no accumulation is expected with these showers. Due to an upper-level disturbance it will be windy tomorrow across the plains of North-central and Central Montana. For the update overnight lows across North-central and Central Montana were lowered to account for faster cooling than was forecast. Wind and WindGust grids were adjusted to better match current observations and trends. Pop grids early tomorrow morning were adjusted to better match the latest Hi-res model guidance. The rest of the forecast is on track. -IG && .AVIATION... 23/00Z TAF Period VFR conditions will prevail during this TAF period. There will be gusty winds during the duration of this TAF period at the KGTF and KCTB terminals and during most of this TAF period at the KHLN, KLWT, and KHVR terminals. Between 09 and 12Z there is a 20% chance for rain showers at the KHVR and KGTF terminals. There will be mountain wave turbulence and isolated instances of low-level wind shear across much of North-central and Central Montana during this TAF period. -IG Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .PREV DISCUSSION... /ISSUED 515 PM MDT Sun Sep 22 2024/ Through Thursday... A shortwave approaching within westerly to northwesterly flow aloft will bring a noon-zero chance for a shower across Central and North-central Montana tonight into early tomorrow, otherwise the only impacts felt from this system will be a breezy rest of the day and increased cloud cover heading into tonight. Monday through Wednesday an upper level ridge will build in from the west, allowing temperatures to climb even further above average. Wednesday looks like the warmest day (Greater than 50% chance for highs at or above 85 F across much of the plains) before the ridge is broken down heading into Thursday. As the ridge breaks down, winds look to become increasingly gusty Thursday and Friday. The chance for a 50 mph gust at Cut Bank is between 30 and 40% Thursday and Friday, with chances increasing closer to the Rocky Mountain Front. Overall the week looks dry, with just a slight chance for rain along the Rocky Mountain Front at times late-week. Saturday and Sunday... Ensemble guidance gives little confidence on how the pattern will evolve next weekend. There is confidence in troughing off the Pacific coast of Canada, but confidence quickly decreases as to how quickly this troughing moves on shore as well as its north/south positioning. Scenarios range from warmer and drier condtions persisting to a cooler and wet latter half of the weekend. -AM && .PRELIMINARY POINT TEMPS/POPS... GTF 49 74 48 83 / 20 10 0 0 CTB 46 71 49 82 / 10 10 0 0 HLN 51 73 49 82 / 10 10 0 0 BZN 42 72 43 79 / 10 10 0 0 WYS 32 65 31 72 / 0 0 0 0 DLN 41 69 41 77 / 0 0 0 0 HVR 47 73 48 81 / 20 10 0 0 LWT 46 67 46 77 / 10 10 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... None. && $$ http://www.weather.gov/greatfalls