Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/25/23
Area Forecast Discussion
National Weather Service La Crosse WI
1000 PM CDT Mon Apr 24 2023
.DISCUSSION...(This evening through Monday)
Issued at 254 PM CDT Mon Apr 24 2023
- Moderate to major flooding continues along the Mississippi
River. The river is forecast to crest from north to south
throughout the week. The biggest river forecast uncertainty is
how much precipitation will fall late this week through the
weekend, and how this will impact river levels.
- High pressure builds in mid-week bringing warmer (near-normal)
temperatures and a couple of dry days.
- Another weekend of periodic precipitation chances ahead.
Despite surface high pressure building across the region, the Upper
Mississippi Valley will remain on the periphery of a mid-level
trough into Tuesday. Scattered generally diurnal showers will
gradually diminish through early evening beneath the mid-level cold
pool as a shortwave trough rotates across northern WI. The highest
concentration of showers will be across WI, with decreasing coverage
to the south and west. Diurnal cumulus will likely develop again on
Tuesday, but shower chances will decrease without the aid of a
stronger shortwave trough as heights begin to rise behind the slowly
High pressure persists through mid-week with temperatures warming to
near-normal. Subsidence will work to keep the region dry into
Thursday. Thursday looks to be the warmest day of the week with high
temperatures in the low to mid 60s currently in the forecast.
PERIODIC PRECIPITATION CHANCES THURSDAY-MONDAY:
A series of shortwave troughs embedded in an amplifying longwave
trough will lead to periodic precipitation chances later this week.
The first round of rain comes Thursday across parts of central
Wisconsin, followed by more widespread scattered precipitation
chances this weekend into early next week. It is a very similar
setup to what we saw this past weekend. There is still over half an
inch of spread in the total QPF between the GEFS and EPS with the
GEFS producing 1.69" and the EPS totaling up to 1.15" in north-
central Wisconsin by Monday evening. The GEFS also has a larger
footprint of precipitation one inch or more, with the EPS
favoring a much drier solution across the southern half of the
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
Issued at 1000 PM CDT Mon Apr 24 2023
CIGS: BKN VFR slowly scattering out late this evening. RAP/NAM still
hint at the potential for low stratus to push west out of eastern
WI, but not as enthusiastic as earlier and not much support from the
SREF. Will hold with VFR. KLSE could see another diurnally driven
BKN deck Tue afternoon,
WX/vsby: The HRRR suggests a smattering of showers would be possible
Tue afternoon, but not as widespread and not favored by most of the
other CAMS models.
Winds: looking to stay on the lighter side (under 10 kts) from the
north to northeast.
Issued at 530 AM CDT Mon Apr 24 2023
The mainstem of the Mississippi River is forecast to continue
rising this week with several locations in Moderate and Major
flooding levels. The latest flood statements have been updated
with the most recent stages.
These river forecasts include the next 24 hours of anticipated
precipitation. The next chance for significant precipitation
could occur Friday into the weekend. Probabilities for 0.50" or
more are 60 to 75% with an inch or more 30 to 45%, however there
remains a large spread in solutions related to placement and
amounts, so continue to check back for updates. Melting snow and
rain continues to work through the Mississippi River system
across parts of MN and northern WI. Any additional rainfall could
affect river stage forecasts and prolong the time period rivers
remain above flood stage.
Area Forecast Discussion...UPDATED
National Weather Service Glasgow MT
758 PM MDT Mon Apr 24 2023
Evening Update: Models not very helpful with current isolated and
disorganized rain showers out there. Made some adjustments this
evening through tomorrow morning, increasing PoPs to err on the
side of caution. When showers actually show up in the models into
our western zones for tomorrow afternoon, the HRRR model seems to
be the only one showing thunderstorm outflow wind boundaries
coming out of the Little Rockies. Would not be surprised to see a
few isolated thunderstorms there. Don`t think it will make it all
the way to Glasgow. Bears watching and re-visiting. ----BMickelson
Previous discussion: Active pattern is expected mainly Wednesday
and Thursday this week, so hang on for the ride.
The upper air pattern today has a ridge over the West coast with
a disturbance dropping southeast across the central Rockies.
Rainshowers are expected to stay just southwest then south of the
CWA through tonight.
Then pieces of energy over Alaska drop into western Canada
tonight and to our north Wednesday and Thursday. This will send a
couple of cold fronts through, the first one arriving late
Tuesday Night/early Wednesday. Sensible weather will come in the
form of mainly wind. It will switch to the NW Wednesday morning
and increase during the day especially over the NE zones with
gusts to around 40 mph.
Another cold front will drop in early Thursday. This disturbance
will have more moisture to work with for the chance of showers and
the possibility of non-severe thunderstorms in the eastern zones.
An upper trough will reside to our east with enough cold air for
the slight possibility of snow late Thursday Night/Friday
Another cold front drops across the area Saturday with just NW
winds with this one. The upper air pattern will have a high
amplitude with a cold airmass to our east and an upper ridge
bringing warm and dry conditions over the Pacific NW. TFJ
UPDATED: 0200Z, Monday night, April 24th
FLIGHT CAT RANGE: VFR
DISCUSSION: Look for SCT-BKN mid and high clouds tonight and
isolated disorganized rain showers slowly diminishing overnight.
Another round of isolated rain showers and a few small
thunderstorms will approach from the west by Tuesday afternoon,
but should fizzle to only vicinity rain showers for KGGW and KGDV
by Tuesday evening.
WIND: E/ESE winds 15-25 knots this evening then decreasing
to SE Tuesday at 10-15 kts. TFJ/BMickelson
Updated Monday PM, April 24th
Hydrology concerns continue to gradually decrease as water levels
continue falling this week. Milk River has dropped below the
action stage of 21 feet at Tampico; dropped to around 28 feet in
minor flooding at Glasgow; and dropped to near 21 feet barely in
minor flood stage at Nashua. Glasgow will drop below minor flood
stage of 25 feet sometime on Thursday this week. Nashua will drop
down below minor flood stage of 20 feet overnight tonight.
For the latest flood/river gauge information, see our AHPS page at
Area Forecast Discussion
National Weather Service Lincoln IL
738 PM CDT Mon Apr 24 2023
Issued at 731 PM CDT Mon Apr 24 2023
Showers will become widespread near and north of I-74 through the
night, but areas further south will see lesser amounts of rain as
the air remains fairly dry. The showers are expected to become
more widely scattered on Tuesday, as a cold front drops southward
through the area. Mid week should largely be dry, before the
risk of showers begins to expand across the region late in the
Issued at 738 PM CDT Mon Apr 24 2023
Despite the impressive amount of radar echoes to our north and
northwest, little in the way of rain is making it to the surface.
Our evening balloon sounding shows quite a bit of dry air below
700 mb, which is the source of the issue. With time this evening,
moistening of the column near/north of I-74 will take place.
However, further south, RAP soundings from Springfield remain
fairly dry below 5,000 feet into tomorrow morning.
Main forecast update this evening was to sharpen up the PoP
trends. Temperatures and winds are largely on track.
.SHORT TERM...(This evening through Tuesday)
ISSUED AT 300 PM CDT Mon Apr 24 2023
Mid afternoon surface map shows a warm front over central Nebraska
into southern IA of NE/IA and into nw IL while 1023 mb high
pressure was near the IN/Ohio border and ridging sw into the mid
MS river valley and Ozarks. Orientation of high pressure ridge has
cut off low level moisture return into central IL as dewpoints
were only in the 20s with temps in the mid to upper 50s. Scattered
to broken high level cumulus clouds with bases of 7-10k ft were
along and west of highway 51 and just east of IL too, so eastern
IL currently enjoying more sunshine this afternoon.
Weak warm air advection driven rain showers to spread eastward
from southern IA/northern MO into central IL during this evening
and mainly affect areas north of a Springfield to Terre Haute line
tonight. SPC day1 outlook has thunderstorms possible tonight over
southern IA/northern MO. Added patchy fog to nw CWA overnight per
trend of HRRR models with vsbys and ceilings lowering in north
side of warm front. Lows overnight in the low to mid 40s central
IL and around 40 in southeast IL where less cloud cover and
lighter winds, with upper 30s over the Wabash river valley.
As weak surface low pressure passes by on Tue it will push the
front back south as a cold front and into southeast IL during Tue
afternoon. Weakening forcing and lack of good moisture to limit
chances of rain showers so just isolated to scattered showers
pushing further south during the day Tue. Guidance has trended
cooler for highs in central IL on Tue with upper 50s to near 60F,
while near 65F from highway 51 south.
.LONG TERM...(Tuesday night through Monday)
ISSUED AT 315 PM CDT Mon Apr 24 2023
High pressure ridge over western Ontario nosing southward into IL
on Tue night and Wed to return dry conditions to the area with
decreasing clouds from the north Tue night and Wed morning. Lows
Tue night in the mid to upper 30s in central IL (mid 30s from I-74
ne where patchy frost possible overnight if NE winds diminish
enough, though currently we have them near 10 mph) and lower 40s
in southeast IL where clouds linger longer. Highs Wed mostly in
the lower 60s, with some upper 50s ne of I-74. Another cool night
Wed night in the upper 30s/lower 40s. Could be another chance of
patchy frost over far ne CWA overnight Wed night where less cloud
Medium range models show an active southern stream with a storm
system moving into the lower MS/TN river valley Thu. This will
increase clouds Wed night and Thu with chance of rain showers into
southern counties Thu afternoon and areas from I-55 east Thu
night. Thunderstorm chances appear to stay south of I-64 Thu
afternoon/evening as instability is much weaker over our CWA.
Highs Thu in the low to mid 60s, coolest in southeast IL where
higher rain chances. Highs in the mid to upper 60s on Friday.
A strong cutoff upper level low digs/develops over the
central/southern plains Fri night and shifts east toward the MS
river valley on Sat. Some models like ECMWF and GEM models have 2
cutoff lows by Sat evening with one near WI and another in the low
MS river valley, while GFS shows one strong cutoff low near
central IL. Either way it looks like showers will be likely moving
into area during Friday night and Saturday along with cooler
temperatures with highs Sat in the upper 50s to near 60F. Cool
highs in the mid to upper 50s Sunday and Monday, and could see
lingering chance of light rain showers on back side of strong
upper level low moving into the central Great Lakes and mid
Atlantic States by Sunday evening.
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 620 PM CDT Mon Apr 24 2023
A warm front will be setting up near KPIA/KBMI this evening, with
showers expanding along the boundary and ceilings lowering.
Greatest impacts will be with MVFR ceilings at KPIA/KBMI toward
05-06Z and persisting into late Tuesday morning. HREF
probabilities of ceilings below 3,000 feet show these sites on the
southern edge of the highest chances, and periods of VFR
conditions would not be unexpected. Will include a TEMPO period of
lower ceilings there from about 09-12Z, before the arrival of low
pressure and a more sustained period of sub-3K ceilings. Overall
improvement is expected toward midday.
Further south, VFR conditions expected to prevail from KSPI-KCMI as
the front remains further north, though an overall lowering of
ceilings to about 3500 feet or so is anticipated early Tuesday