Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/01/24
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
750 PM CST Thu Feb 29 2024
.KEY MESSAGES...
- 30-50% chance for rain/snow south of I-72 tomorrow morning into
early afternoon. Nonzero, but low (10%) chance for freezing
rain. Any wintry precip accumulations will be minimal.
- Gusty south winds will accompany a weather system Sunday into
Monday, with gusts upwards of 35 mph expected. Chances for
hitting Wind Advisory criteria, 45 mph, are generally less than
30%.
- Widespread showers and perhaps thunderstorms are expected with
the same system Monday into Tuesday. While uncertainty remains
high in severe potential, its potential looks low (less than
15%) at this time.
&&
.UPDATE...
Issued at 750 PM CST Thu Feb 29 2024
Early evening satellite imagery shows some high clouds drifting
across the forecast area. Dew points are largely in the teens, but
despite this, southerly winds should remain elevated enough to
keep temperatures from free-falling overnight. Little change was
needed to lows tonight, generally a couple degrees either side of
30.
Our evening sounding is parched, with HRRR forecast soundings
near Springfield at sunrise still quite dry below 600 mb. Sampling
of soundings around the forecast area shows it will take a couple
hours to really get moistened up, by which time temperatures
should be in the mid 30s or so and precipitation transitions more
to a rain/snow mix.
Geelhart
&&
.DISCUSSION...
Issued at 104 PM CST Thu Feb 29 2024
A return to southerly surface winds marks the beginning of a warming
trend that will bring high temps into the upper 40s this afternoon
amidst clear skies. A mid-level system lifting northeast through the
region will bring a 30-50% chance for some rain and wintry mix
across areas mainly south of I-72 tomorrow morning into early
afternoon, with temps behind it suppressed a bit by lingering cloud
cover. However, the warming trend will return Saturday as southerly
flow increases yet again to bring temps into the 60s.
With the system tomorrow morning, models continue to struggle in
identifying which p-type will be predominant. HREF currently shows a
roughly 20-50% chance for both rain and snow (with snow the more
probable p-type further north), but no members within the ensemble
are depicting any freezing rain. Still, forecast soundings from the
HRW-ARW show a sufficient warm nose aloft that if surface temps drop
to sub-freezing by dynamic cooling during the morning there could be
some freezing rain. Chances for that are estimated at around 10%, so
it`s not expected though it could make for some slick pavement
(especially on sidewalks) if it does occur. LPMM QPF is less than a
tenth of an inch everywhere, while the ensemble max is just over a
tenth, so if that should all come down as snow (and it shouldn`t)
there`d be an inch or less of accumulation on grassy surfaces in the
heaviest band. Winter weather impacts are thus not expected.
The warming trend in temperatures will culminate either Sunday or
Monday, depending on the timing of passage of a cold front which
will slow as it approaches the area. Ahead of that front,
deterministic models bring 850mb temps to the +12-15 degC range,
suggesting surface temps could rise well into the 70s on one or both
of those days. The deterministic models also show decreasing gaps
between north-south oriented isobars, indicating a tightening
pressure gradient favorable for gusty south winds which the ECMWF
ensemble mean suggests will peak around 35-40 mph late Sunday into
Monday. NBM fortunately suggests the chances for hitting advisory
criteria - highest in our northwest - are generally less than 30%.
NBM brings rain (thunder) chances to around 50-70% (20-30%) with
that washed out cold front late Monday into Tuesday, though
instability displaced well south of favorable forcing should limit
severe potential. Beyond Tuesday, ensemble spread in the pattern
increases, leading to uncertainty in temperatures and precip
potential, but CPC advertises a 70% chance for above normal
temperatures throughout days 6-10 (Wednesday, March 6th through
Sunday, the 10th).
Bumgardner
&&
.AVIATION... (For the 00z TAFs through 00z Friday Evening)
Issued at 525 PM CST Thu Feb 29 2024
Main aviation concerns will begin toward mid-late Friday morning, with
ceilings and visibilities lowering to MVFR conditions as a
rain/snow mix moves into central Illinois. Longest-lasting lower
ceilings appear to be from KBMI-KDEC east, though HREF
probabilities below 2,000 feet are generally in the 30-40% range.
KSPI/KPIA probabilities are also around 40%, but for a shorter
period (generally centered around 16-18Z). Improvements are
expected from west to east during the afternoon, though
visibilities may be slower to respond.
While the gusty south winds will begin to die down with sunset,
expect winds near 10 knots to continue much of the forecast
period.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Shreveport LA
933 PM CST Thu Feb 29 2024
...New UPDATE, SHORT TERM...
.UPDATE...
Issued at 921 PM CST Thu Feb 29 2024
Bumped lows down from NBM and added a little thunder for I-30.
&&
.SHORT TERM...
(Tonight through Saturday Night)
Issued at 921 PM CST Thu Feb 29 2024
Despite the rain falling, our dew points are not saturated except
for Marshall and Ruston. The remaining spread will allow for
slightly cooler lows than the NBM and we have gone a category
lower in of our several zones. Also, radar trends are lining up
nicely with the HRRR and no changes have been made to restructure
pops anywhere overnight. We have been following a rouge cell with
an occasional strike along the I-30 corridor and added that
slight chance to definite and likely shower areas. Mount Pleasant
and most recently for Texarkana both carrying thunder in the last
ob or two. We should wake up to most of this rainfall to our east
with the last push out of deep east TX and NE LA around daybreak.
Also, the winds are more relaxed and line up well with the
CONSShort, which we have loaded in through Friday. /24/
&&
.LONG TERM...
(Saturday through next Wednesday)
Issued at 239 PM CST Thu Feb 29 2024
With a substantial area of ridging builds along an axis reaching up
the Plains and spreading into the Mississippi and Ohio Valleys. As
promised, a rapid warming trend will accompany this pattern, with
highs returning to the 70s Saturday, even pushing 80 at some sites
on what will feel like an early arrival of Spring. Aside from a few
scattered clouds, abundant sunshine and highs in the lower 80s
nearly areawide will make Sunday afternoon feel like a taste of
Summer. Lows will accordingly climb back into the 50s, even 60s at
some sites once again by Monday morning.
As the weekend continues, our next system will be taking shape in
the form of area of troughing over the Pacific Northwest, which will
propagate east, swinging its attendant frontal boundary south across
the Plains by late Sunday, bringing with it our next significant
chance for rainfall. Precip looks to begin overnight Sunday into
Monday, with showers and storms overspreading the entire region once
again shortly after daybreak Monday. The position of this and
subsequent upper level systems to our north will establish a
sustained southwest flow pattern overhead, favoring continued
areawide rainfall chances through early Tuesday, when the region
looks to enter a short-lived respite before the next rainfall
arrives Wednesday and continues through to the end of this extended
forecast period. At this point, severe weather does not look likely
within the ArkLaTex, but as always, we will be closely monitoring
these systems as the forecast evolve in the coming days.
Rain-cooling effects will result in milder- but still above average-
high temperatures next week, generally ranging in the 70s
throughout, with our warmest sites approaching 80, and an emerging
cooling pattern for our northern sites which will return to more
seasonable 60s, while accompanying lows return from the 60s back to
the 40s and 50s.
/26/
&&
.AVIATION...
(00Z TAFS)
Issued at 458 PM CST Thu Feb 29 2024
Mostly low VFR ceilings attm with spotty light rain but no
reduction in VSBY noted. LFK just came in with our first MVFR
ceiling and look for MVFR ceilings to become widespread later this
evening into the overnight hours. Cannot rule out brief MVFR VSBYs
as well with precipitation becoming scattered to numerous across
our airspace but the precipitation should pull out our our eastern
airspace near or shortly after sunrise Fri morning. MVFR ceilings
will likely hang on until late morning/early afternoon across most
areas before ceilings scatter out. MVFR ceilings may hang in
through the end of the TAF period and beyond across our southeast
third. Winds will gradually become ESE and SE overnight through
the day Friday with speeds generally under 10kts.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 42 66 48 78 / 80 0 0 0
MLU 43 64 46 75 / 80 20 0 0
DEQ 36 61 40 76 / 70 0 0 0
TXK 38 62 45 76 / 80 0 0 0
ELD 38 62 43 76 / 70 10 0 0
TYR 40 68 50 79 / 60 0 0 0
GGG 41 67 48 78 / 70 0 0 0
LFK 44 71 50 79 / 70 0 0 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
SHORT TERM...24
LONG TERM....26
AVIATION...13
Area Forecast Discussion
National Weather Service Tallahassee FL
808 PM EST Thu Feb 29 2024
...New UPDATE, MARINE...
.UPDATE...
Issued at 806 PM EST Thu Feb 29 2024
Forecast remains on track from the near term discussion below.
&&
.NEAR TERM...
(Through Friday)
Issued at 353 PM EST Thu Feb 29 2024
Afternoon satellite and surface observations show a 1036-mb high
centered over the TN/OH Valley, cold front draped across the Central
Gulf/Central FL, and mid-latitude cyclone traversing the Plains.
These features are are responsible for mostly cloudy skies areawide
via upper cirrus streaming from the SW and lower stratocumulus
moving semi-clockwise in the lower levels (950-825 mb) through
Apalachee Bay & the Suwannee Valley. Overcast conditions combined
with efficient moisture recovery will make for an unseasonably warm
night as temperatures drop to the 50s, particularly along/south
of the FL stat line. Elevated easterly winds should preclude fog
development and instead, just prompt low stratus during the
overnight/morning hrs.
For tomorrow, attention turns to a batch of rain showers marching
towards the Tri-State area from the Lower MS Valley. Rapid moist
advection ahead of this activity fosters some instability to support
at least a slight chance of thunderstorms during the afternoon. The
best potential is where low-60s dew points overspread our FL and
southernmost GA counties. Some storms may be strong given modeled 0-
6 km bulk shear of 40-50 kts and a peak LLJ of 30+ kts. Gusty winds
and rotating cells would be the primary concerns. Isolated severe
weather is possible. The main questions are how much instability can
be realized, and will there be any mesoscale features (e.g., low
pressure) that form from the associated convection?
The 18Z HRRR has the convection entering the FL Panhandle/SE AL late
tomorrow morning with peak activity in the afternoon around the I-10
corridor. Some cells in the simulated reflectivity field show bowing
segments, which suggests a wind threat while semi-discrete cells
could be capable of brief spin-ups along the coast and offshore. As
for high temperatures, there is likely to be quite the spread from
NW (low/mid 60s) to SE (70s). The lower readings will be from rain-
cooled air.
&&
.SHORT TERM...
(Friday night through Saturday night)
Issued at 353 PM EST Thu Feb 29 2024
With a shortwave continuing to lift out across the southeast, we`ll
see rain chances begin to decrease from west to east throughout
Saturday. With dew points in the 60s across most of the region,
there is some opportunity for a few strong thunderstorms and gusty
winds. Most of the activity is expected to wind down by Saturday
night. The lack of cold air advection behind this shortwave means
we`ll remain in a moist and conditionally unstable environment, with
dew points remaining in the upper 50s to mid 60s post-shortwave.
Expect overnight temps generally in the mid to upper 50s with
daytime highs generally in the low to mid 70s.
&&
.LONG TERM...
(Sunday through Wednesday)
Issued at 353 PM EST Thu Feb 29 2024
There is a brief lull in widespread activity in the long term before
another disturbance looks to move through by midweek. With moisture
remaining present and a relatively weak LLJ looking to move across
the region, the possibility for low-end severe is there, but we`ll
need to reassess in the coming days. Otherwise, expect scattered
showers throughout the long term as diurnal instability takes
advantage of conditional large-scale instability as a stationary
boundary sags across the region.
Expect daytime highs generally in the mid 70s to low 80s with
overnight lows generally in the mid 50s to low 60s.
&&
.AVIATION...
(00Z TAFS)
Issued at 621 PM EST Thu Feb 29 2024
A BKN-OVC deck between 025 and 045 is streaming in from the west
across the terminals. MVFR cigs are likely through the night at
ECP, maybe creeping into TLH overnight, gradually filling in near
sunrise at all other terminals. SHRA will begin moving into ECP
and DHN shortly after 12z, spreading eastward through the area
during the day. Cigs will fall into IFR and LIFR through the day
from west to east. A few TSRA are possible late in the afternoon
at DHN and ECP.
&&
.MARINE...
Issued at 806 PM EST Thu Feb 29 2024
Northeast winds will reach small craft advisory levels mainly west
of Apalachicola tonight into Friday morning, where significant
wave heights will peak around 5 feet. Winds will will decrease and
become southeast by Friday afternoon through early next week, as
a frontal boundary remains draped to the south of the waters.
There is also increasing potential for sea fog this weekend into
early next week.
&&
.FIRE WEATHER...
Issued at 353 PM EST Thu Feb 29 2024
Easterly flow will transition to southeast and south through the
upcoming weekend. With southeast and southerly flow developing,
expect a quick transition to a moist and wetter pattern with rain
chances increasing from west to east on Friday and then lingering
into Saturday. Rain chances decrease some on Sunday, but a moist
airmass will remain in place so expect fire weather concerns to
stay low from Friday into and the upcoming weekend. Only concerns
could be the development of patchy fog over the weekend in the
overnight hours, but confidence in fog potential remains low.
&&
.HYDROLOGY...
Issued at 353 PM EST Thu Feb 29 2024
With all rivers below flood stage and not much widespread precip
accumulation expected throughout the next week, there are currently
minimal flooding concerns.
&&
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur by calling the office or tweeting us @NWSTallahassee.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 68 55 71 61 / 0 10 60 70
Panama City 67 56 70 62 / 10 20 80 70
Dothan 62 52 64 57 / 10 20 90 70
Albany 63 50 63 55 / 10 20 80 80
Valdosta 66 52 70 60 / 0 10 70 60
Cross City 69 55 78 60 / 0 0 20 40
Apalachicola 65 58 68 62 / 10 10 60 70
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through late Friday night for FLZ108-112.
High Rip Current Risk until 4 AM EST /3 AM CST/ Friday for
FLZ114-115.
GA...None.
AL...None.
GM...Small Craft Advisory until 9 AM CST Friday for GMZ750-752-770-
772.
&&
$$
NEAR TERM...IG3
SHORT TERM...Oliver
LONG TERM....Oliver
AVIATION...Young
MARINE...LF
FIRE WEATHER...Dobbs
HYDROLOGY...Oliver
Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
432 PM MST Thu Feb 29 2024
.KEY MESSAGES...
217 PM MST Thu Feb 29 2024
- Dry, windy, and seasonably warm conditions are expected tonight
through tomorrow, which will bring very high to extreme
grassland fire danger.
- Cooler, more unsettled conditions return late this weekend
through early next week, with occasional chances for light
precipitation anticipated.
&&
.DISCUSSION...(This Evening Through Thursday)
Issued at 217 PM MST Thu Feb 29 2024
Water vapor imagery this afternoon depicts an amplified ridge
extending from the central Plains northward through much of
Saskatchewan. This ridge is positioned between longwave troughs
over the eastern Pacific/Northwest Coast and eastern Canada.
Plumes of deep moisture are evident along the downstream side of
the former trof, extending from near the Great Basin northward
into Canada. These plumes are contributing to passing cirrus
across far northern portions of the area. Otherwise, skies are
largely clear, which-- coupled with southerly to southwesterly
flow regionwide--are contributing to well above average
temperatures this afternoon.
As the aforementioned large-scale trof approaches the region
tonight, a tightening pressure gradient across the Black Hills and
increasing low-level to midlevel momentum will likely contribute
to breezy/windy conditions from the northeastern WY plains
eastward to the foothills. Across the foothills, soundings
indicate a low-level maximum of westerly/southwesterly flow of
40-50 kt near the height of a low-level thermal inversion. Many
12z HREF members (generally outside of the HRRR) indicate fairly
widespread gusts exceeding wind advisory criteria (45 mph or
greater) across the foothills beginning late this evening/early
tonight and persisting into the morning. The HRRR does eventually
suggest some gusts around advisory criteria by around daybreak. By
10z, HREF mean gusts reach 45 mph along the I-90 corridor from
Rapid City northward, then southward along Highway 79. Altogether,
HREF probabilities suggest that advisory-level gusts are probable
to likely (60-80%) over much of the foothills and lower
elevations of the Black Hills, with chances peaking in the 06-12z
time frame. As such, confidence is high enough to introduce a Wind
Advisory for the foothills.
Windy conditions--though probably sub-advisory criteria--are then
expected to expand post-daybreak. The strong westerly to
southwesterly downslope flow will again contribute to warm, dry,
and deep boundary layers, bringing another afternoon of well above
average temperatures and elevated fire danger. Increasing upper-
level cloudiness may limit heating/mixing somewhat across our west
and northwest, but highs in at least the 50s are anticipated even
in the cooler spots tomorrow, with lower 70s in warmer locations
across southwestern and south central SD.
Low-level trof crosses the northern Plains tomorrow evening into
the night. Compared to prior days, trof appears to largely be a
glancing blow, with only a brief northerly component to low-level
flow and associated limited impacts to low-level temperatures
before warm-air advection returns early Saturday. This warm-air
advection will likewise be short-lived as another trof/surface
cyclone develops over southeastern MT/north central WY on
Saturday. Regionwide pressure falls and a tightening pressure
gradient will bring another breezy to windy day, especially over
northeastern WY.
Periods of enhanced midlevel to upper-level Q-vector convergence
and low-level to midlevel frontogenesis will contribute to
occasional chances for light precipitation from Friday afternoon
through Saturday evening, especially over northwestern SD where
more persistent isentropic ascent can augment moistening of an
antecedent dry air mass. More widespread chances for light
precipitation (largely snow) arrive behind a more pronounced cold
front late Saturday into Sunday. As was the case yesterday, light
precipitation is probable across much of our area through Monday--
especially the northwestern two-thirds of the region, where
probabilities of 0.1" of liquid exceed 50%. However, amounts
greater than 0.25" are a bit less likely, with highest
probabilities (40-45%) only over localized portions of the central
Black Hills and northwestern SD plains.
&&
.AVIATION...(For the 00Z TAFS Through 00Z Friday Evening)
Issued At 430 PM MST Thu Feb 29 2024
VFR conditions are expected through the forecast period. Gusty
southwest winds over parts of northeastern Wyoming and the Black
Hills tonight will spread to the Black Hills foothills late
tonight. Low level wind shear will develop tonight over the
plains of western South Dakota tonight, including the KRAP
terminal. The gusty southwest winds will spread across the South
Dakota plains Friday morning.
&&
.FIRE WEATHER...
Issued At 217 PM MST Thu Feb 29 2024
Dry, windy, and seasonably warm conditions will contribute to
very high or extreme fire danger over much of the southwestern and
south central SD plains tomorrow. More broadly, elevated or near-
critical fire weather conditions are expected over much of the area,
with minimum relative humidity values in the 17 to 30 percent range,
sustained westerly to southwesterly winds of 15 to 30 mph gusting
to 40 mph, and high temperatures from the upper 50s to the lower
70s. Elevated fire weather conditions may persist into Saturday
across northeastern WY and far southwestern SD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory from 11 PM this evening to 9 AM MST Friday for
SDZ025-026-072.
Wind Advisory from 11 PM this evening to 11 AM MST Friday for
SDZ027-074.
WY...None.
&&
$$
DISCUSSION/KEY MESSAGES...Sherburn
AVIATION...Helgeson
FIRE WEATHER...Sherburn