Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/20/24
Area Forecast Discussion
National Weather Service Bismarck ND
1000 PM CST Mon Feb 19 2024
.KEY MESSAGES...
- Areas of fog are possible tonight into Tuesday morning far
northwest and north central.
- Otherwise dry with seasonable temperatures north and mild to
unseasonably warm temperatures central and south through the
Thursday.
- After a brief cooldown northeast on Friday, mild to unseasonably
warm temperatures encompass the entire forecast area this
weekend.
- Continued mild and possibly wetter conditions next week.
&&
.UPDATE...
Issued at 943 PM CST Mon Feb 19 2024
Minimal changes needed for late evening update. Although low
clouds/fog have yet to push into far northern portions of our
area, the area of clouds and fog have expanded substantially
over along the Manitoba/Saskatchewan border. With the southern
edge continuing to creep our way, still expect some development
into our area. Therefore, will leave fog/cloud forecast as is
at this point.
.UPDATE...
Issued at 543 PM CST Mon Feb 19 2024
For early evening update, main change was to increase the
potential for some fog over far northwest/north central North
Dakota. Models are becoming a little more consistent with
bringing some fog in from Saskatchewan/Manitoba. Therefore, have
increased coverage a bit. Remainder of forecast looks fine.
&&
.DISCUSSION...
Issued at 113 PM CST Mon Feb 19 2024
Overall, the forecast looks very quiet through the weekend, with
only a few things to note.
First: There is the potential for some low clouds/fog mainly
along the International Border tonight into Tuesday morning.
Currently, weak low pressure is situated over north central ND,
with a weak cold front extending southwest into east central
Montana. Early this morning, low stratus/fog developed north of
the front over southeast Saskatchewan into far southwest
Manitoba. There is some guidance that suggests that low stratus
may sneak down into north central/northeast North Dakota late
tonight into Tuesday morning. During the late morning discussion
we mentioned that the RAP was dropping the low level RH
farther south than the HRRR. Since then, the HRRR, has trended
farther south with the lower RH into Tuesday morning.
The aforementioned surface low tracks southeast into west
central MN by Tuesday morning with a weak surface high dropping
into north central ND. There may be some increasing thin high
clouds, but overall the setup looks reasonable for some low
stratus/patchy fog in the north central. A slowly diminishing
snowpack over Burke, Mountrail, Renville and portions of Ward
and Bottineau counties may aid in the low level moisture and
resulting fog formation. There are some indications the fog
could drop down past the Highway 200 corridor. We added some
patchy fog and increased sky cover in the north central for now
and will pass this along to the evening shift.
We`ll see another low develop over southern Saskatchewan later
in the day Tuesday and drop southeast on a track similar to
(maybe a bit farther south and west) our current surface low.
This will keep the northern CWA cooler and cloudier than the
central and southern CWA through mid week. Any precipitation
with these weak surface systems tracking across the area would
be negligible and currently the NBM is not depicting pops. A
stray sprinkle/flurry can`t be completely ruled out Tuesday,
although would most likely remain north of the CWA.
Second: A more significant wave drops through the northern
stream late in the work week. Deterministic models show a
shortwave trough dropping southeast from Manitoba into Ontario
in the Thursday-Friday timeframe, with it`s attendant surface
cold front tracking through our neck of the woods later Thursday
into Friday. The mid-upper level forcing will remain well east
of the forecast area, so the main impact may be maybe a little
wind but mostly cooler temperatures. With the system so far too
our east, it looks like the cooler temperatures will impact the
northeast CWA much more than the southwest.
A cluster analysis shows that there is a slight tilt (60% to
40%) in favor of a warmer solution, meaning either/or more
ridging to our northwest with an eastward displacement of the
Hudson Bay low. Rather than a more zonal/northwest upper flow
to our northwest and/or the Hudson bay low closer to our
forecast area. Overall, the differences should lead to little
impacts due to the expected dry weather.
It`s maybe a bit more interesting looking at the NBM 1D
ensemble temperatures. For example, on Friday Dickinson shows a
narrow 4 degree spread between the 25th/75th percentile (24 vs
28) for the morning low and a 6 degree spread between the
25th/75th percentile (46 vs 51) for the daytime high. If we
look just to the northeast of our CWA at Devils Lake for the
same timeframe, we see an 11 degree spread between the
25th/75th percentile for the low Friday morning (13 vs 24) and
a 17 degree spread between the 25th/75th percentile for the
Friday afternoon high (24 vs 41). The morning low 75th
percentile and the afternoon high 25th percentile are both 24
degrees. Also, the lower and upper quartiles are quite similar
at Dickinson but the lower quartile is much wider at Devils Lake
meaning, there are likely more significant outliers in the
lower quartile and a better chance of seeing forecast highs too
high over the northeast CWA on Friday. That trend also continues
into the morning lows on Saturday. Back in western ND the
clusters show a reasonable agreement of all model ensembles,
and perhaps too low. As was discussed in the previous
discussion, the deterministic forecast highs Friday and Saturday
for Dickinson are at or below the 25th percentile. So basically
more of the same, cooler northeast and warmer southwest.
Third: those warmer temperatures in the southwest Friday spread
across the entire forecast area for the weekend. There will
still be a bit of a gradient from north to south, but nothing
like during the work week. For now it looks like even the
far north, including the Turtle Mountains area should feel the
warmth this weekend.
And finally, just a peek ahead as the 6-10 and 8-14 day outlooks
are continuing to favor above normal temperatures, moreso east
than west. In addition, both the 6-10 day and the 8-14 day
precipitation outlooks slightly favor above normal
precipitation. There is also a small signal in the CIPS analogs
for above normal precipitation late February into early March
over portions of central and into eastern ND.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 543 PM CST Mon Feb 19 2024
Areas of fog and/or low stratus may drop from southeastern
Saskatchewan/southwestern Manitoba into parts of far
northwest/north central North Dakota tonight, resulting in IFR
conditions. At this time, this looks to stay north of the KMOT
terminal, but would not be surprised if some patchy fog moved
through. Thus, have posted VCFG in the KMOT TAF, and noted
scattered low clouds. Will continue to monitor through the
evening. Otherwise, VFR conditions are expected to prevail at
all other locations.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...JJS
DISCUSSION...TWH
AVIATION...JJS
Area Forecast Discussion
National Weather Service Grand Forks ND
649 PM CST Mon Feb 19 2024
.KEY MESSAGES...
- The probability of widespread impactful weather is low (less
than 10%) through early next week.
&&
.UPDATE...
Issued at 646 PM CST Mon Feb 19 2024
High clouds moving east thru SE ND into WC MN. Otherwise skies
are clear. HRRR and conshort/NBM 4.1 guidance indicating low
clouds and fog growing in NW ND into SE Sask/SW MB and likely to
stay just west of the fcst area....but something to watch for
the overnight as it could spread into Cando and areas west of
DVL.
&&
.DISCUSSION...
Issued at 153 PM CST Mon Feb 19 2024
Short term...Tonight through Tuesday night
A few high clouds around to move east northeast across the
south associated with a weak upper level trough lifting
northeastward from SD tonight through early Tuesday. A weak
surface trough is in place across central/eastern SD associated
with the upper wave, and will swing a trough axis from west to
east from central ND through the forecast area tonight into
Tuesday. This will allow southeasterly winds to shift around to
the west to northwest for Tuesday. Overall temperatures might be
a few degrees cooler behind the trough axis for Tuesday highs
especially in the central/north/northwestern portions of the
forecast area. Dry conditions expected through Tuesday night.
Long Term...Wednesday through Monday
Very quiet weather is anticipated from Tuesday onwards. West to
northwesterly low level flow and a lack of snowpack will allow
temperatures to remain well above average through Thursday. A cold
front Thursday night will drop temperatures for Friday. There is
quite a bit of spread within the NBM of how cool temperatures will
be behind the front. This spread is due to disagreements in the
placement of the Canadian trough as it propagates eastward. Even in
the coolest of scenarios, temperatures only fall to near average.
The cool down will be short lived, as temperatures will start to
rebound over the weekend as troughing over the western US builds in
to the Northern Plains.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 646 PM CST Mon Feb 19 2024
VFR conditions anticipated into Tuesday. Devils Lake area may
see some lower clouds due to low cloud/fog development west of
the area in north central and northwest ND. 30 percent chance.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Riddle
DISCUSSION...MJB/Rafferty
AVIATION...Riddle
Area Forecast Discussion
National Weather Service North Platte NE
553 PM CST Mon Feb 19 2024
.KEY MESSAGES...
- Above average temperatures will continue most of the week,
with another warmup expected over the weekend.
- Limited precipitation potential through the week.
- Enhanced fire weather concerns continue tomorrow, with gusty
winds across northwestern Nebraska and the Sandhills.
&&
.SYNOPSIS...
Issued at 322 PM CST Mon Feb 19 2024
Upper air analysis and water vapor satellite imagery this morning
show a trough in the polar jet over New England, with a large ridge
over the United States and Canada west of the Mississippi River,
extending up to Alaska. The subtropical jet has a trough over the
southeastern United States, ridging over the Desert Southwest
extending up to Montana, and another pronounced trough off the West
Coast with an embedded upper level low off the coast of northern
California. Afternoon surface analysis places low pressure systems
in north central North Dakota along the Canadian border, eastern
South Dakota, central Kansas, and along the Rocky Mountains in
Colorado. Western and north central Nebraska is under a high
pressure center. Satellite imagery shows a few high clouds across
north central Nebraska and a shrinking snow pack over northwestern
Nebraska.
&&
.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 322 PM CST Mon Feb 19 2024
Under the influence of the upper level ridge and surface high
pressure, will continue to see mostly clear skies across western and
north central Nebraska through tomorrow night. Latest HRRR guidance
points towards warm air advection at the 850 mb layer tomorrow
afternoon, and forecast soundings remain optimistic for strong
mixing conditions. With the mixing conditions in mind, expecting
that tomorrow afternoon may be gusty at times, with the strongest
gusts over portions of northwestern Nebraska and the Sandhills.
As for temperatures, kept a bit more on the conservative side of
guidance, as warm air advection aloft was expected to come in later
in the afternoon. Temperatures will be widespread mid to upper 60s
across most of southwestern Nebraska, with upper 50s across northern
portions of the state. With that in mind, would not be surprised to
see a few stations south of I-80 report 70 degrees tomorrow
afternoon.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 322 PM CST Mon Feb 19 2024
Wednesday night, the subtropical ridge is pushed eastward by the
trough. As this trough pushes east, a low pressure system will
develop in Colorado and track through Kansas, which may generate
some light showers across southwest Nebraska. Previous model and
ensemble guidance was very light on amounts, between 0.01 to 0.1
inches. Latest guidance has trended that amount down even further,
with a very slim possibility (less than 10%) of seeing measureable
precipitation across the Panhandle and southwest Nebraska, with the
bulk of precipitation expected to the southwest in northeastern
Colorado.
Following the passing of the system, temperatures are expected to
cool down slightly on Thursday, but still be slightly above seasonal
averages, mainly in the 50s. A second ridge develops in the
subtropical jet over the Desert Southwest, then will begin its
eastward trek over Nebraska late Friday. As this second ridge builds
over western Nebraska, another warm up is expected this weekend,
with current guidance suggesting temperatures in the 60s again.
Ensemble guidance from the European and Canadian ensembles hints
that temperatures may even be greater than 70 degrees, however,
confidence is somewhat low given the spread in the ensembles at
this time.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 552 PM CST Mon Feb 19 2024
Quiet and dry conditions are expected for the most part through
Tuesday. The only major weather concern will be some stronger winds
Tuesday afternoon across the entire region. West southwesterly wind
gusts up to 20 knots are possible by mid-afternoon before
diminishing around sunset.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Richie
SHORT TERM...Richie
LONG TERM...Richie
AVIATION...Kulik
Area Forecast Discussion
National Weather Service Marquette MI
917 PM EST Mon Feb 19 2024
.KEY MESSAGES...
- Possible upslope stratus/patchy fog developing late tonight
over the central.
- Dry with highs near 40 for Tuesday and Wednesday.
- Cooler and chances increase for lake effect snow from around
20% Thursday to near 60% by Friday, possibly (around 30%)
lingering through the weekend.
- A warmup into next week comes with increasing chances for
precipitation.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 333 PM EST Mon Feb 19 2024
Confluent nw flow aloft and sfc ridging resulting in plenty of
sunshine today with temp readings thus far today ranging from the
upper 20s and lower 30s north to mid to upper 30s interior west and
south central.
Surface high pressure and anticyclonic flow will continue the dry
conditions into tonight. The only real forecast problem tonight will
be the potential for stratus/patchy fog forming late tonight/early
Tuesday in a developing upslope/onshore se flow off Lake Michigan.
The NAM, RAP and HRRR fcst soundings all hint at the possibility of
stratus/fog developing over central Upper Mi so have included this
in the grids. Look for min temps mostly ranging through the teens,
although the typical cold spots over the interior west/central could
dip lower, closer to 10F.
&&
.LONG TERM /TUESDAY THROUGH MONDAY/...
Issued at 402 PM EST Mon Feb 19 2024
As broad ridging moves across the southern US, corresponding 500mb
height rises will lead to a warming and dry trend despite some
shortwaves passing late Tuesday and Wednesday. Gridded MOS guidance
shows highs climbing to around 40 both days. In spite of the
shortwaves evident on 500mb forecast charts and ensemble MSLP plots
showing a weak low passing north of Lake Superior, this forecast
will keep PoPs below 15% through Thursday morning. The Euro
ensemble suite shows a 6% or less chance of measurable QPF over
the UP while the GEFS and Canadian ensemble broadly in the 5-15%
range with a few localized spots mainly along Lake Superior up
to 30% PoP. Even if some clouds can overcome the ridging and dry
air enough to precipitate, the precipitation is not going to be
impactful, though PoPs may trend upwards in future forecast
packages if the Euro trends towards the Canadian and GEFS and
depending how the CAMs handle the forcing.
The next pattern shift comes into the weekend as troughing gradually
builds over the Upper Great Lakes and eastern CONUS as a whole. The
strongest passage of 500mb vorticity comes Friday with 850mb cold
advection rates as much as 25C/12hr are possible per the 12Z GFS.
This means 850mb temperatures plummet into a lake-effect favoring
regime once again, with lake-850mb delta Ts near -25C for portions
of the weekend. Uncertainty does exist regarding how long lake
effect holds on as the 12Z GFS shows a surface trough passing late
Saturday into Sunday with some warmer air at 850mb, but that could
also potentially bring synoptic precip as the GEFS is trending
towards bringing a clipper low in the area over the late weekend.
Made only few minor adjustments to the midnight shift`s PoPs given
the uncertainty.
Beyond the weekend, another warmup is expected with ridging building
in for the early week period. LREF probabilities of highs above
freezing are around 50% Sunday, followed by around 75% Monday and
over 80% Tuesday. Tuesday`s record warm low temperature (32, 1998)
may be in danger as the LREF shows around a 40% chance that the
temperature never falls below freezing. While the spread is very
large in timing, the GEFS consistently shows a surface low passing
through the Upper Great Lakes region next week with some members
bringing pressure as low as 980mb, but as uncertainty is still sky
high, this is a mere novelty in the extended forecast instead of an
actual feature of concern.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 917 PM EST Mon Feb 19 2024
VFR conditions continue across the TAF sites tonight through Tuesday
as winds pick up from the south with time. However, some FG is
possible (50% chance) over KSAW near dawn and early Tuesday morning;
this FG could bring conditions down to airport mins (50% chance).
However, I`ve improved the cigs to above airport mins at KSAW since
the last TAF issuance given that only the NAMNest is highlighting
the FG now over KSAW early Tuesday morning and the previous
forecaster said he made it 100 ft cigs by mistake. Expect the FG
over KSAW to clear out to VFR conditions by late Tuesday morning.
An additional feature we are seeing is the development of upslope
low-end MVFR cigs across the Keweenaw this evening. With the winds
being fairly stubborn over there, thinking it won`t be until late
tonight for cigs to improve to VFR.
&&
.MARINE...
Issued at 402 PM EST Mon Feb 19 2024
Winds will be below 20 kt until Tuesday afternoon, when a dry trough
passes over the region and southerly wind gusts increase to 20-25
kts. Winds then fall below 20 kt Tuesday night through Thursday when
troughing builds across the Upper Great Lakes. As winds become
northwesterly Thursday evening, wind gusts in the west half pick up
to 20-25 kt with winds up to 30 kt in the east half. These gusts
maintain strength Friday before falling below 20 kt Saturday. The
best chance for a gale in that time period would be Friday, where
model data suggests a nearly 50% chance of some gale force gusts in
the east half. Moderate freezing spray is also possible late
Thursday into early Saturday over the east half of the lake.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Voss
LONG TERM...GS
AVIATION...TAP
MARINE...GS