Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/10/24
Area Forecast Discussion
National Weather Service La Crosse WI
557 PM CST Sat Nov 9 2024
.KEY MESSAGES...
- Rain will continue to move through the region late this
afternoon and evening. A second round of rain (with isolated
thunder) will move through the region for the morning and
early afternoon on Sunday. Rainfall amounts of around 0.25" or
less are expected in most locations.
- Seasonable to seasonably warm temperatures next week. Rain
chances return late Tuesday night and Wednesday.
&&
.DISCUSSION...
Issued at 128 PM CST Sat Nov 9 2024
Rest of Today - Sunday: Periodic Showers This Weekend
GOES-16 satellite imagery depict a very prominent mid-latitude
cyclone centered over portions of the Great Plains this afternoon
associated with a uniformly closed low pressure center. As this low
continues to eject northeast bound, isentropic lift associated with
700-850mb theta-e advection will continue to instigate showers
further northeast throughout the remainder of the afternoon and
evening. Overall, guidance has tended to favor lighter amounts with
the recent 09.12z HREF only having lower probabilities (0-40%) for
amounts over 1/10". That being said, radar trends certainly show
pockets of heavier rainfall rates across northeast IA so would not
rule out some locally higher amounts of 0.2 to 0.4" with this first
round of precipitation.
As we move past the evening and into the overnight hours, the band
of showers lifts northeast of the region as the recent CAMs continue
to indicate minimal precipitation within a relatively weakly forced
regime overnight ahead of the low pressure center. Eventually
towards daybreak on Sunday, the closed low moves overhead bringing
additional chances for precipitation with the 09.12z HREF having
slightly higher probabilities (60-80%) of over 1/10" of rain during
the morning hours. With some weak instability present in the long-
range HRRR soundings, would not rule out a rumble of thunder or two.
Overall though, expecting rainfall amounts from now through Sunday
to be generally around 0.25" or less with locally higher amounts
possible within more robust showers and any storms.
Sunday night into the workweek:
Sunday night into Monday, a shortwave trough is forecast to rotate
through the U.P. of Michigan. At this time, the HREF is mainly dry,
however a few rain mixed with snow showers could clip parts of north
central Wisconsin. 09.12Z HREF has a zero joint probability of
850mb temperatures dropping below 0 deg C. and a trace or more of
precipitation, however by 15/18Z, the 09.00 deterministic
models do cool 0 to 5 below zero north of Black River Falls.
HREF probabilities through 12Z Monday for a trace of
precipitation are 10 to 50%, but only 0 to 30% for 0.01. Lows
have cooled a few degrees from the previous forecast and are
currently forecast to range from the mid 30s north of BCK
northward to lower 40s Monday morning, if the cooling occurs
earlier or if any precipitation is falling, mixed precipitation
could occur. It will be something to keep an eye on. Highs
Monday should be in the 40s and to mid 50s.
Ridging is forecast to build in for Tuesday with highs in the 50s.
This warmth is short-lived as the next trough is already working
east through the Rockies. Rain chances increase late Tuesday night
into Wednesday with the trough and associated cold front. The track
of the surface low is farther north into northern MN/southern
Canada, thus the more organized rainfall appears to be tracking
north of the local area. 09.00Z LREF probabilities are 45 to 60%
for 0.10" or more.
Ridging returns later Wednesday night through Friday with continued
seasonably warm temperatures from the mid 40s to the mid 50s. Beyond
Friday, there is some disagreement as to how the next trough over
the West Coast deepens or if it will be less amplified moving
into the Rockies sending some energy ahead of it with a warm
front/precipitation developing Friday night into Saturday. At
this time, the rainfall probabilities are 10 to 20% for 0.10" or
more, so stay tuned.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 553 PM CST Sat Nov 9 2024
Rain showers continue to move through the region this evening
with generally VFR visibilities. The heavier showers should end
southwest to northeast over the next few hours with light
drizzle and perhaps some patchy fog continuing overnight.
Visibilities are expected to remain VFR overnight but may drop
to MVFR at times in heavier precip/denser fog. Ceilings are
expected to begin to drop to IFR conditions over the next few
hours behind the showers with sites in central Iowa already reporting
500-900ft ceilings with some sites reporting 400ft ceilings.
KRST would be the most likely to dip into LIFR conditions for
ceilings as we head into the overnight hours, although
probabilities of this are low (< 30%). Showers are expected to
develop again Sunday morning with more restricted visibilities,
generally around 2SM in the more robust showers. There is the
potential for some rumbles of thunder with these showers, but
confidence is on the low end so have left thunder out of the
TAFs for now. Conditions will begin to improve Sunday afternoon.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
DISCUSSION...Naylor/Zapotocny
AVIATION...Falkinham
Area Forecast Discussion
National Weather Service Billings MT
506 PM MST Sat Nov 9 2024
.KEY MESSAGES...
- Mainly warmer and dry conditions for most areas through the
weekend.
- Weak disturbance brings rain/snow showers to the southern
mountains and foothills Sunday.
- Periods of increased winds over the western foothills tonight
into next week.
&&
.UPDATE...
Quiet night upcoming as we are underneath flat ridging ahead of a
Pacific shortwave along the coast. Upper low over NE continues to
drift to the northeast, and any light precip that may have eked
its way into the far southeast corner of MT has exited. HRRR is
suggestive of a little fog in southeast Carter County tonight and
this seems plausible given the 6pm observation of 40/34 at Alzada,
and expectation of clearing w/ light winds tonight. Have tweaked
pops/wx and winds, otherwise forecast is in good shape. JKL
&&
.DISCUSSION...
Today through Sunday night...
Brief ridging continues over the region today, keeping conditions
mild and dry. An upper level low over Nebraska is bringing
precipitation right along the southeast MT border. Southeast parts
of Carter county have a small chance of precip through this
afternoon. Early morning Sunday, a weak pressure gradient sets up
for a gap wind pattern at Livingston. Models have trended downward
and the chance for hitting 50 mph is about 20%. Late Sunday
morning, a weak disturbance will pass through the region, with the
best chance for precipitation being snowfall for the
Beartooth/Absaroka mountains (less than 2 inches likely). Lower
elevations have a 10% chance or less at seeing any precipitation.
High temperatures will be in the 50s to low 60s today, slightly
cooling to the 50s Sunday. Low temperatures will be in the upper
20s to 30s Sunday and Monday mornings. TS
Monday through Saturday...
Warm and dry conditions are in the forecast for Monday. During
this time, winds look to increase along the western foothills
around Livingston, Nye, and Big Timber with gusts in the 30-45 mph
range. As we get into Monday night, gap winds look to increase
around Livingston to Nye ahead of a Pacific cold front passage.
With this, the chance of seeing a 50 mph or greater gap wind gust
remains around 60 percent. Once the front moves through Monday
night into Tuesday morning, the gap wind threat will come to an
end. Across the rest of the region, westerly winds will increase
behind the front Tuesday with 20 to 40 mph wind gusts common over
the plains of southeastern Montana. From Big Timber to Harlowton,
winds may be a little stronger Tuesday with gusts to 50 mph
possible (50-60 percent chance).
Outside of winds, the chance of precipitation increases in the
west Monday night as the next weather system approaches. At this
time, the best chance of precipitation across the area comes
Tuesday morning when there is a 20 to 90 percent chance of
precipitation, highest over the mountains and lowest near Miles
City and Baker. The chance of precipitation decreases Tuesday
evening into early Wednesday morning as upper level ridging builds
back in. With this system, the wave looks to remain open with
little cold air. Therefore, precipitation amounts look to remain
relatively light. Over the lower elevations, there is a high
chance precipitation amounts remain below 0.20 inches. In the
mountains, a couple inches of snow is likely, but the chance of
seeing 6 or more inches of snow drops quickly outside of the
highest peaks of the Beartooth/Absaroka Mountains (60 percent
chance).
Upper level ridging will bring warmer and dry conditions back to
the forecast for most Wednesday into Friday. The low amplitude
nature of the ridge may allow light snow showers to persist over
the western mountains during this time though (15-30 percent
chance). Another weather system is possible by next weekend, but
uncertainty remains. Arends/RMS
&&
.AVIATION...
Winds over the western foothills (KLVM) will be breezy (25-40
mph)through the morning hours. VFR conditions will prevail. TS
&&
.PRELIMINARY POINT TEMP/POPS...
Sun Mon Tue Wed Thu Fri Sat
-----------------------------------------------------------
BIL 038/057 032/060 040/051 031/054 037/059 031/050 029/040
01/E 10/B 14/W 00/U 00/U 11/B 33/W
LVM 033/054 032/060 032/046 027/050 034/053 028/047 025/040
02/W 10/N 36/W 11/N 21/N 23/W 43/J
HDN 030/058 030/061 036/051 028/055 031/060 028/052 027/042
01/B 10/B 16/W 10/U 00/B 12/W 33/W
MLS 030/058 030/058 034/053 030/055 031/059 029/052 028/042
00/B 00/B 03/W 10/U 00/B 01/B 22/W
4BQ 030/059 032/059 036/052 031/054 033/060 030/053 030/043
00/U 00/U 05/W 10/U 00/B 01/B 22/W
BHK 028/057 025/050 031/053 027/052 029/059 028/053 026/045
00/U 00/N 02/W 10/U 00/U 00/B 22/W
SHR 029/060 027/062 033/052 024/054 029/061 027/052 025/042
00/U 10/U 07/W 20/U 00/B 01/B 34/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.
&&
$$
weather.gov/billings