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
404 FXUS65 KTFX 102034 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 234 PM MDT Mon Jun 10 2024 .SYNOPSIS... This afternoon and evening an upper-level trough moves through North-central Montana which will bring isolated showers and maybe a few rumbles of thunder to the Hi-Line. For the rest of the area today will be dry, breezy, and warm. Tuesday and Wednesday will be warm, dry, and windy with the strongest wind gusts along the Rocky Mountain Front and adjacent plains. Dry conditions will persist until Friday when Southwestern Montana has the potential for showers and thunderstorms when a new upper-level system begins to move into the area. Next weekend it will be cool with the potential for precipitation. && .DISCUSSION... This afternoon through Wednesday... This afternoon a fast- moving upper-level trough moves across the Hi-Line. The upper-level trough will bring isolated showers with a few rumbles of thunder along the Hi-Line this afternoon and evening. Some the showers could sneak a little farther south in North-central Montana. For the rest of North-central, Central, and Southwestern Montana it will be dry, breezy, and warm this afternoon and evening. Due to warm temperatures melting snowpack in combination with recent rainfall rivers, streams, and creeks are cold, fast flowing, and near bank full across Southwestern Montana. Due to no additional rainfall expected until Friday, there are no flood concerns at this time. Continue to monitor the forecast for updates. On Tuesday an upper- level ridge moves over North-central, Central, and Southwestern Montana with strong upper-level flow. This will cause breezy to strong winds and wind gusts across the area for Tuesday along with warmer temperatures. Along the Rocky Mountain Front there is a 60 - 80% chance for wind gusts exceeding 55 mph on Tuesday. Along the plains adjacent to the Rocky Mountain Front there is a 50% chance for wind gusts exceeding 55 mph on Tuesday. For the lower-elevations of North-central, Central, and Southwestern Montana there is a 30 - 50% chance for wind gusts exceeding 40 mph on Tuesday. Tuesday evening a weak and dry cold front moves through North-central, Central, and Southwestern Montana. This will slightly cool down high temperatures across the area on Wednesday. On Wednesday there will be strong upper-level zonal flow, which will keep breezy to strong winds and wind gusts in place across North-central, Central and Southwestern Montana. Along the Rocky Mountain Front there is a 70 - 90% chance for wind gusts exceeding 55 mph on Wednesday. Along the plains adjacent to the Rocky Mountain Front there is a 50% chance for wind gusts exceeding 55 mph on Wednesday. On Wednesday across Northern Blaine County there is a 60 - 80% chance for wind gusts exceeding 47 mph. For the rest of the lower-elevations of North- central, Central, and Southwestern Montana there is a 30 - 60% chance for wind gusts exceeding 40 mph on Wednesday. Even with low humidity and breezy to strong winds on Tuesday and Wednesday there will be limited to no fire weather concerns due to recent rainfall and green fuels. Thursday and Friday... On Thursday an upper-level ridge will move over North-central, Central, and Southwestern Montana. This will allow the dry conditions to persist. It will also allow there to be sunny skies with slightly above seasonal average temperatures for North-central, Central, and Southwestern Montana. On Friday the upper-level ridge remains in place over North-central, Central, and Southwestern Montana. On Friday afternoon/early evening an upper- level disturbance associated with a surface cold front will move through North-central, Central, and Southwestern Montana. This will bring the potential for showers and thunderstorms to Southwestern Montana. This will need to be monitored for updates. Friday will be the warmest day of this forecast period. On Friday the Fort Benton area to Great falls and the Helena and Gallatin Valleys have a 25 - 50% chance for high temperatures of 90 degrees or greater. Saturday through next Monday...On Saturday clusters indicate that an upper-level trough will move over North-central, Central, and Southwestern Montana. The strength of the upper-level trough in the four clusters varies. However, this indicates that the weather pattern will change to have cooler temperatures with the possibility for precipitation for North-central, Central, and Southwestern Montana. On Sunday three clusters (85% of ensemble members) keep the upper-level trough over North-central, Central, and Southwestern Montana. The other cluster (15% of ensemble members) has zonal flow over the area. This indicates that most likely the weather on Sunday will be similar to that on Saturday for North-central, Central, and Southwestern Montana. On Monday clusters indicate that the upper- level trough will remain over the area. This means that for the Saturday to next Monday period it will be cooler with the potential for precipitation across North-central, Central, and Southwestern Montana. -IG && .AVIATION... 10/18Z TAF Period Scattered rain showers and isolated thunderstorms will remain possible through trough the early evening hours tonight along and north of the US Hwy 2 corridor (i.e. KHVR to KCTB terminals); however, the probability for any one shower impacting the KHVR or KCTB terminals through 03z Tuesday is below a 30% chance. Scattered to broken VFR/low-VFR CIGS are expected through the afternoon hours today across all terminals as the disturbance responsible for the early morning precipitation slides east, with breezy and gusty west to northwest winds at the terminals in Central and North Central Montana (i.e. KHLN, KGTF, KLWT, KCTB, and KHVR). Mountains will be obscured at times through 03-09z Tuesday. - Moldan Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .PRELIMINARY POINT TEMPS/POPS... GTF 50 83 50 79 / 10 0 0 0 CTB 48 79 46 72 / 10 0 0 0 HLN 53 85 53 83 / 0 0 0 0 BZN 46 84 49 84 / 0 10 0 0 WYS 40 74 42 78 / 0 10 0 0 DLN 46 82 48 83 / 0 0 0 0 HVR 51 84 54 79 / 50 0 0 0 LWT 47 79 48 78 / 10 0 10 10 && .TFX WATCHES/WARNINGS/ADVISORIES... None. && $$ http://www.weather.gov/greatfalls