Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/03/24
Area Forecast Discussion
National Weather Service Burlington VT
932 PM EST Sat Mar 2 2024
.SYNOPSIS...
An upper trough moving through the eastern Great Lakes combined with
a weak low moving up the East Coast will bring a period of light
rain to the region through midnight. Thereafter mostly dry weather
will prevail until a low pressure system approaches the North
Country as early as Tuesday night. A warming trend will additionally
continue through the middle of next week, with high temperatures
nearing or exceeding record temperatures in some locations.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
As of 924 PM EST Saturday...Main change for this forecast update
was the blend in some of the latest high res model guidance like
the HRRR into PoPs to better depict the movement and departure
of showers overnight/tomorrow morning. PoPs will shift north and
east throughout the next 6-12 hours, and it looks as though we
will be in the clear from rain showers by around 5 AM Sunday.
That being said, patchy fog is already developing across the
forecast area and based on model soundings, could persist longer
into Sunday morning. Visibilities are not too low at the moment,
with the lowest spots sporting 0.75-2.00 miles, and we are also
getting reports on social media of low visibilities on roadways.
This is something we`ll be monitoring for the potential need for
a Special Weather Statement, but at this time, it is not
warranted. Otherwise, forecast is on track with lows expected to
be mild in the 30s for most and a cloudy sky lingering through
most of tomorrow. Previous discussion below:
Previous Discussion...Precipitation has finally begun to fill
in across the forecast area in earnest this afternoon as weak
low pressure moving up the East Coast combines with an upper
trough moving through the eastern Great Lakes. As the trough
centers over the Champlain Valley later this evening midnight,
it will keep the coastal low east of our region and kick deeper
PWATs eastward as well with rain tapering off from the
Adirondacks westward by midnight, Champlain Valley during the
pre-dawn hours Sunday, and eastern Vermont shortly before
sunrise. Basin average QPF amounts are expected to be in the
0.2-0.4" range, but with little to no snowpack below 2000 feet,
river rises aren`t expected to cause any problems. Clouds,
precip, and patchy fog will keep low temps mild tonight ranging
through the 30s.
Dry weather follows for the remainder of the period through Sunday
night as high pressure builds in aloft, but a stubborn low level
inversion will keep clouds abundant through most of the day Sunday,
and potentially not fully into Monday. As such, we`ve lowered the
max temp forecast for Sunday considerably from previous forecasts,
with most locations warming only in the upper 40s to a few low 50s
in the southern valleys. It`s likely no max temp records will be
reached, though low hanging fruit of 52 at KMPV could be close.
Several high min temp records continue to be in jeopardy though for
both March 3rd and 4th with Sunday night lows close to tonights in
the 30s to around 40. See the climate section below for more details
on these records.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
As of 322 PM EST Saturday...Monday will feature a southerly return
flow as moderately strong surface anticyclone drifts east across the
Gulf of St. Lawrence and Canadian Maritimes. Temperatures will be
well above normal with daily high temperature records likely to be
broken for March 4th, though some question remains on amount of
sunshine with expectation of lingering clouds/moisture beneath
subsidence inversion near 5kft. NWP consensus is for better chances
for clearing across nrn NY into the Champlain Valley, especially by
afternoon. Skies may persist mostly cloudy east of the Greens,
though the potential for breaks in the overcast will be higher than
on Sunday. With 850mb temperatures rising to +4C to +6C (highest
west), should see afternoon highs in the mid-upper 50s east of the
Greens, and into the lower 60s for the Champlain Valley and points
wwd. A few readings in the mid 60s will be possible in the St.
Lawrence Valley.
Deep layer ridging remains in place for Monday and Tuesday. Lows
will be well-above normal Monday night in the low-mid 40s, except
upper 30s across far nern VT. A mid-level shortwave trough lifting
northward from the Mid-Atlantic region will begin to spread
increasing clouds and rain showers for southern and eastern sections
through the day on Tuesday. Should see a quarter to third inch of
rainfall across south-central VT on Tuesday (55-60 PoPs), with
lesser amounts to the north and west (30-40 PoPs). Temperatures will
remain mild, with highs generally in the low-mid 50s. There`s a
better chance that the St. Lawrence Valley will be north and west of
most of the clouds and precipitation. Thus, highs should be closer
to 60F in our far western zones including the lower elevations of
St. Lawrence County.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 322 PM EST Saturday...Temperatures to remain above average for
the mid and latter half of next week. Main concern will be southern
stream shortwave trough and attendant surface low expected over the
mid-Atlantic region Wednesday night, and subsequent progression into
the Northeast. Of the deterministic suite, the 12Z GFS is the
furthest north and west with a deepening low over CT/MA and
potential for widespread moderate to possibly heavy precipitation
toward Thursday morning. Development of closed 700mb low to our
south in this solution is also favorable for heavy stratiform
precipitation. Antecedent air mass is warm, so will need to rely on
dynamic and diabatic cooling to help lower snow levels Thursday
morning. At this point, appears there is a better potential for rain
in most valley locations with higher elevation snows. The 12Z ECMWF
takes this same system just southeast of the 40N 70W benchmark and
has a weaker sfc low development that results in lesser
precipitation chances across VT. The 12Z Canadian is similarly
offshore with a stronger sfc anticyclone anchored across Quebec
resulting in a drier solution across the BTV forecast area. Remains
a system worth keeping an eye on, but with relative lack of model
agreement PoPs Wed Night into Thursday remain in the 30-40% range.
Current trends indicate deep-layer ridging toward the end of the
week with potential for some sunshine and high temperatures in the
low-mid 40s for Friday and Saturday.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
Through 00Z Monday...Steady rain has come to an end across
northern New York, but that is being replaced by IFR/LIFR
conditions as areas of fog and mist develops given the
unseasonably mild and moist conditions near the surface. The
LIFR conditions are currently across the St Lawrence valley,
with KSLK seeing VFR conditions. VFR conditions are also being
currently observed at the Vermont terminals, with exception of
KMPV, which is seeing IFR ceilings. The IFR/LIFR conditions are
expected to spread eastward into KSLK and eventually the Vermont
terminals towards 06z. That will also coincide with the end time
of the steady rain as it exits Vermont from west to east between
04z and 06z. South/southeast winds at 5-10 kt are also expected
to become light and variable for a time between 04z and 08z
before turning northerly at 5-10 kt after 09z. Conditions become
mainly MVFR or better after 15z.
Outlook...
Sunday Night: Mainly VFR, with areas MVFR possible. NO SIG WX.
Monday: Mainly VFR, with areas MVFR possible. NO SIG WX.
Monday Night: Mainly VFR, with areas MVFR possible. NO SIG WX.
Tuesday: Mainly VFR, with areas MVFR possible. Chance SHRA.
Tuesday Night: VFR/MVFR conditions possible. Chance SHRA.
Wednesday: VFR/MVFR conditions possible. Chance SHRA.
Wednesday Night: Mainly VFR, with areas MVFR possible. Chance
SHRA, Chance SHSN.
Thursday: MVFR. Chance SHRA, Chance SHSN.
&&
.CLIMATE...
Record High Maximum Temperatures and Current Forecast:
March 3:
Record Forecast
KMPV: 52/1964 48
March 4:
Record Forecast
KBTV: 57/1953 63
KMPV: 55/1974 57
KPBG: 56/1953 62
KMSS: 58/1964 63
KSLK: 60/1936 60
Record High Minimum Temperatures and Current Forecast:
March 3:
Record Forecast
KBTV: 37/1923 38
KPBG: 34/1965 38
KSLK: 35/2020 32
March 4:
Record Forecast
KBTV: 40/1974 40
KPBG: 37/1974 34
March 5:
Record Forecast
KBTV: 43/1979 43
KPBG: 39/1964 47
KSLK: 37/1964 41
March 6:
Record Forecast
KBTV: 41/1894 41
KPBG: 35/2009 38
KSLK: 34/2009 33
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Lahiff
NEAR TERM...Lahiff/Storm
SHORT TERM...Banacos
LONG TERM...Banacos
AVIATION...Chai
CLIMATE...Lahiff/Kremer
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
917 PM CST Sat Mar 2 2024
.KEY MESSAGES...
- Strong southerly winds will develop on Sunday...with gusts
increasing to 35-45mph.
- Thunderstorm chances return Monday into Tuesday. Severe weather
probabilities are low (less than 5 percent) at this time.
&&
.UPDATE...
Issued at 916 PM CST Sat Mar 2 2024
It`s a clear, mild, and breezy evening across central IL as low
pressure in the lee of the Rockies results in continued
southeasterly winds. The main change in the forecast at this time
was to trend less aggressive on the cloud cover tonight.
Nighttime microphysics satellite imagery currently shows clouds
near/northeast of Indianapolis, with little signs of new
development across SW IN. The latest runs of the HRRR and RAP also
removed any cloud cover, whereas earlier runs had a broken
stratus deck developing/moving in overnight. The updated forecast
caps cloud cover at 30-40% (as opposed to 60-70%), and even this
may be too high. With less cloud cover expected, adjusted the low
temps a degree or two cooler.
Erwin
&&
.SHORT TERM... (Tonight through Sunday)
Issued at 312 PM CST Sat Mar 2 2024
The gradient between a ridge of high pressure over the Ohio River
Valley and a low developing in the lee of the Rockies will tighten
sufficiently to create strong S/SE winds across central Illinois
tonight. Boundary layer moisture currently present across
Indiana/Kentucky will advect northwestward into the area tonight,
resulting in increasing cloudiness. HRRR/RAP both suggest clear
skies early this evening, followed by overcast conditions across
at least the eastern half of the KILX CWA after midnight. There is
still some uncertainty about how far W/NW the clouds will spread,
although recent runs of the HRRR/RAP have become more aggressive.
At this time, will go with mostly cloudy skies along/east of I-55
after midnight into Sunday morning before winds become S/SW and
the moisture gets quickly scoured out of the area by Sunday afternoon.
NAM continues to indicate a 50-60mph 925mb jet developing from
Missouri northeastward to the southern Great Lakes tonight. Some
of this higher momentum air will get mixed to the surface during
the day Sunday once the low overcast breaks up, resulting very
gusty winds. 12z HREF probabilities show a 100% chance of gusts
exceeding 30mph, with a 60-70% chance of exceeding 40mph along the
I-55 corridor by afternoon/evening. Thanks to the strong S/SW
flow and increasing amounts of sunshine, afternoon highs will soar
into the lower to middle 70s.
Barnes
.LONG TERM... (Monday through Next Saturday)
Issued at 312 PM CST Sat Mar 2 2024
As low pressure tracks from eastern Wyoming tonight into Manitoba,
it will gradually pull a cold front into the region on Monday.
12z Mar 2 models are in much better agreement with the timing of
the front, with model consensus showing the boundary approaching
the Illinois River by late Monday afternoon. While the pre-frontal
airmass will become moderately unstable with SBCAPEs reaching
1000-1500J/kg, the strongest deep-layer shear will be displaced to
the west of the boundary. As a result, the GFS Ensemble
probabilities of exceeding SBCAPE of 500J/kg and 0-6km bulk shear
of 40kt are less than 10% immediately along the front. Given this,
think widespread severe weather is highly unlikely...although a
few strong cells with gusty winds/hail cannot be ruled out Monday
evening as the front pushes eastward into central Illinois. As
with previous forecasts, have focused highest PoPs across the
Illinois River Valley late Monday afternoon/evening, then further
east Monday evening/night. A few showers may linger across the
E/SE KILX CWA in Tuesday morning: however, trends are suggesting a
return to dry weather everywhere Tuesday afternoon through
Wednesday night. After that, another weather system may spread
showers back into the region late Thursday into Friday.
Temperatures will initially be well above normal in the middle 70s
on Monday, then will fall back into the 50s Wednesday-Friday.
Barnes
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 515 PM CST Sat Mar 2 2024
Southeast sfc winds will continue through the overnight hours.
LLWS is a concern tonight, as southwest winds at 1.5kft increase
to around 40-45 knots. Guidance did trend lower with the 1.5kft
wind speeds, but given the directional change still kept LLWS in
the TAFs. MVFR ceilings are expected to develop this evening, most
likely across eastern IL and then the probability decreases with
westward extent. There is some uncertainty as to how quickly these
ceilings dissipate Sunday morning, but once the ceilings do
dissipate, breezy southerly winds will gust to around 30 knots on
Sunday.
Erwin
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Northern Indiana
629 PM EST Sat Mar 2 2024
.KEY MESSAGES...
- Dry conditions persist through Monday afternoon.
- Highs in the mid to upper 60s on sunday, then low 70s Monday!
- A cold front moves through late Monday through midday Tuesday,
bringing 40-70% chances for rain and maybe a few thunderstorms.
- Temperatures moderate with highs in the 50s the rest of the
week.
&&
.DISCUSSION...
Issued at 228 PM EST Sat Mar 2 2024
As temperatures warm into the upper 40s this afternoon, clouds have
decreased. Visible GOES East satellite imagery shows few to no
clouds along the lakeshore, with the most dense areas of cloud
cover still in northwest Ohio. Clouds should continue decrease
from west to east this afternoon as diurnal heating progresses.
This evening and overnight, RAP and NAM soundings show a layer
of some low level stratus developing. For now, have maintained
partly cloudy skies across much of the forecast area, with
mostly cloudy skies in northwest Ohio. Lows will be in the upper
30s.
It will be a beautiful end to weekend; There will be intermittent
clouds and sun on Sunday, with highs climbing into the low to mid
60s! Winds increase out of the south on Sunday afternoon with gusts
up to 30 mph, especially west of IN-15. These winds will fuel warm
air advection, which is why highs will be 20-25 degrees above
normal on Sunday!
A large area of low pressure ejects out of the Rockies and deepens
over the Dakotas this weekend. We will be in the warm sector Monday
as the attendant warm front associated with this system lifts north.
WAA continues as highs Monday will be in the low 70s! Then, the
attendant cold front sweeps across the Central Plains Monday
and reaches the Midwest by early Tuesday morning. I do not have
a lot of confidence in this cold front on Monday night producing
more than a half an inch of rain at most. The latest runs of
the NAM, GFS, and ECMWF all delay the onset of the rain until
after 00Z Monday and show very limited moisture (dewpoints in
the upper 40s to low 50s, only briefly in the mid 50s). With
insufficient moisture, CAPE will be limited as well. In fact,
the NAM actually shows precipitation along the front completely
falling apart over the forecast area Tuesday morning. Also, this
is looking more and more likely that the bulk of the
precipitation will be overnight, which further decreases my
confidence. Because of this, I`ve elected to slow down PoPs
until 00Z and reduce chances for rain to 70% or less. It appears
as if the majority of the rain comes through between 06-12Z
Tuesday, with a few showers lingering through 18Z.
The mild pattern continues next week as temperatures moderate in the
50s. Another weather system sets up over the Mid Mississippi River
Valley at the end of the week, bringing additional chances for
rain/storms on Friday.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 626 PM EST Sat Mar 2 2024
Return flow to continue through the TAF period. Scattered
diurnal clouds will persist at and under the base of a weak
subsidence inversion.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory from 7 AM Sunday to 1 AM EST Monday for
LMZ043-046.
&&
$$
DISCUSSION...Johnson
AVIATION...Skipper
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
532 PM CST Sat Mar 2 2024
.KEY MESSAGES...
-Warm temperatures will continue on Sunday with some parts of
central Missouri possibly reaching record highs. The warm and
relatively dry air along with breezy conditions will produce
elevated fire danger across parts of central and northeast
Missouri on Sunday afternoon.
-A cold front will move into the area Monday afternoon and
continue slowly southeast through Tuesday. Showers and
thunderstorms will accompany the front. Some of the storms could
be strong on Monday afternoon/evening.
-The remainder of the week will be cooler, but temperatures will
still be 5-10 degrees above normal.
&&
.SHORT TERM... (Through Late Sunday Night)
Issued at 251 PM CST Sat Mar 2 2024
A short wave trough which is currently over the Pacific Northwest
will move east across the Rockies into the northern Plains tonight.
This will force low level cyclogenesis over the Dakotas Sunday
morning and the resulting low will track north-northeast through
Monday. The wind will increase late tonight into Sunday as the low
deepens over the Plains, and the pressure gradient tightens.
Southwest flow aloft will bring 12-14+C temps at 850mb into the
region. GFS and RAP forecast soundings show deep mixing so highs in
the mid 70s to low 80s should be easily attainable.
Latest model guidance has slowed the cold front associated with this
system a bit, and it now looks like Monday should be mostly dry,
with showers and some thunderstorms moving into central and
northeast Missouri during the latter half of the afternoon. This
convection will continue Monday night into Tuesday as the front
tracks slowly to the southeast. The severe threat remains
uncertain, as the GFS is now showing instability approaching 2000
J/Kg across parts of central Missouri Monday afternoon, but the ECMWF
has backed off a little from previous runs with MUCAPE at or below
1000 J/Kg. LREF probability of CAPE greater than 1000 J/Kg maxes
out at 00Z Tuesday at around 35 percent across southeast Missouri and
southern Illinois, which lends a little more confidence toward the
lower instability ECMWF solution. With all that said, I still
wouldn`t be surprised if we see some strong storms late Monday
afternoon/evening.
Carney
&&
.LONG TERM... (Monday through Next Saturday)
Issued at 251 PM CST Sat Mar 2 2024
The rest of the week will be cooler behind front, but still around 5-
10 degrees above normal for this time of year. The semi-persistent
long wave trough which has been sitting over the western U.S.
attenuates somewhat during the first half of the week and moves
eastward where it phases with another wave over the Plains. This
produces a generally wet pattern for the latter 1/2 of the work
week, and possibly into the weekend. LREF cluster analysis
indicates a good deal of uncertainty associated with both the
amplitude and timing of this late-week trough. However the clusters
(all 4 of them) do show this system affecting the Mid-Mississippi
Valley Thursday, Friday, and potentially into Saturday. The pattern
doesn`t really look favorable for strong/severe storms, so if it
works out it looks like a period of much-needed beneficial rain.
Carney
&&
.AVIATION... (For the 00z TAFs through 00z Sunday Evening)
Issued at 532 PM CST Sat Mar 2 2024
Dry and VFR flight conditions are likely to persist through the TAF
period. There is potential for patchy IFR/MVFR fog and stratus to
develop across southeastern MO and southwestern IL early Sunday
morning, but the probability of this fog and stratus to drifting
into St. Louis metro terminals is low. A south-southwesterly low-
level jet will also develop overnight, contributing to marginal LLWS
at KCOU, KJEF, and KUIN. Southerly winds are forecast to increase
quickly Sunday morning with the onset of occasional gusts of 22 to
32 kt continue into the evening.
Pfahler
&&
.FIRE WEATHER...
Issued at 251 PM CST Sat Mar 2 2024
Very warm temperatures in the upper 70s to low 80s are expected on
Sunday across parts of central and northeast Missouri.
Additionally, a surge of drier air from the Plains will make its
way into parts of Missouri during the warmest part of the
afternoon. This will produce relative humidity values around 30
percent and just below. This the low relative humidity combined
with sustained winds between 15 and 20 mph and dry fuels will
produce elevated fire danger conditions across parts of central
and northeast Missouri on Sunday afternoon.
Carney
&&
.CLIMATE...
Issued at 253 AM CST Thu Feb 29 2024
Another round of very warm weather is expected this weekend into
early next week. Daily record high temperatures are possible. The
table below lists the record highs at the climate locations in our
service area.
SAT MARCH 2 SUN MARCH 3 MON MARCH 4
St Louis 82 in 2022 85 in 1974 79 in 1974
Columbia 82 in 2022 80 in 1983 80 in 1938
Quincy 77 in 1976 77 in 1946 73 in 1961
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Melbourne FL
1019 PM EST Sat Mar 2 2024
...New UPDATE, MARINE, AVIATION, PREV DISCUSSION...
.UPDATE...
Issued at 1017 PM EST Sat Mar 2 2024
Mid-levels ended up drier than forecast, which slammed the door on
nearly all deep convection today. This is well depicted by the 00Z
TBW sounding, which actually rang in with a whopping 3,166 J/kg of
SBCAPE, but a PWAT of only 1.23" and a MidRH of 36 pct (this kills
the storm). A similar story is told by the MCO ACARS soundings,
though with a little more moisture in the mid-level, which is how
a few lightning storms have managed to develop across the interior
this evening, including one near Leesburg that produced small
hail.
As of 10 PM the sea breeze collision has produced a couple
lightning storms near Like Kissimmee, one of which has persisted
for a bit while riding boundaries to the northeast. Further north,
lightning storms have developed north of Leesburg again which the
HRRR and NBM have become enthusiastic over, so increased PoPs
across the north, but am ready to be burned again. This kind of
activity can be expected through the night, where a bit of
enhanced broad ascent or pockets of surface instability initiate
rounds of showers and lightning storms, especially as moisture in
the mid-levels continues to slowly increase from the stalled front
to the north drooping closer. Stronger storms capable of
occasional cloud to ground lightning, gusty winds 40 to 50 mph,
small hail, and heavy downpours remain possible, though the
chances are generally lower than earlier today.
&&
.MARINE...
Issued at 1017 PM EST Sat Mar 2 2024
Tonight...Isolated lightning storms remain possible over the local
Atlantic waters through the night, especially over the Gulf
Stream. South to southeasterly winds 5-10 kts back to easterly
around 5 kts near the Volusia coast. Seas 3-5 ft.
&&
.AVIATION...
(00Z TAFS)
Issued at 1017 PM EST Sat Mar 2 2024
ISO SHRA/TSRA expected to continue through the night, but low
confidence in timing and location, so TAFs continue VCSH/VCTS
through 10Z and will issue short-fused TEMPOs as needed. CIGs
forecast to drop to IFR-LIFR at the northern terminals around 10Z,
and DAB may drop to MVFR as early as 06Z. CIGs recover to VFR
between 13Z and 15Z, then rain chances increase again in the
afternoon with the sea breeze collision around 23Z. However,
TEMPOs for TSRA impacts may be needed as early as 18Z if outflow
from the north develops storms prior to the sea breeze collision.
&&
.PREV DISCUSSION...
Issued at 1017 PM EST Sat Mar 2 2024
Tonight-Sunday...After activity along the sea breeze collision kicks
off, westerly steering flow will push activity back towards the
coast late tonight, with scattered showers and isolated storms
possible through the overnight hours. Based on hi-res guidance,
activity will likely begin to diminish slightly towards daybreak
across east central Florida, which will lead to a short break
between rainfall and storms on Sunday morning. A weak disturbance in
the Gulf of Mexico will move across the peninsula on Sunday, with
moisture remaining elevated locally (PWATs 1.3-1.5"). Coupled with
the development of the east coast sea breeze that will move inland,
model guidance continues to indicate yet another afternoon and
evening of scattered showers and isolated storms. Similar to today,
any storms that are able to develop with this activity on Sunday may
be capable of producing occasional lightning strikes, gusty winds 40
to 50 mph, small hail, and brief heavy downpours. Activity is
forecast to diminish across the area Sunday night as the weak
surface disturbance moves offshore and drags a weak boundary across
the peninsula.
Cloud coverage will remain high tonight through Sunday, which will
keep temperatures similar to the last several days, with overnight
lows in the low to mid 60s and afternoon highs in the upper 70s to
low 80s.
Monday-Tuesday...A diffuse surface boundary remains draped near to
just north of east central Florida early next week. Meanwhile,
shortwave pulses traverse the area aloft. These pulses will be
enough to help generate daily showers and isolated lightning storms,
mainly during the afternoons. Ample moisture, with PWATs 1.3-1.6",
will work to create scattered showers and storms, with the highest
coverage across the interior. MUCAPE 800-1400J/kg is forecast,
though drier air aloft will be a limiting factor to updraft growth,
especially on Monday. Colder temperatures aloft will maintain a
small hail threat, though they will be warming through the period,
with -14/15C forecast Monday and -10/11C on Tuesday. A few storms
could become strong, with gusty winds and locally heavy downpours.
Easterly winds 5-10mph Monday veer southeasterly on Tuesday and
increase to up to 10-15mph. Temperatures will warm through the
period, with upper 70s to lower 80s Monday becoming the lower to mid-
80s Tuesday. Expect temperatures along the coast to be 5+ degrees
cooler, especially along the Volusia Coast, as Atlantic water
temperatures remain cool.
Wednesday-Saturday...The aforementioned boundary dissipates into mid-
week. Models have come into better agreement that a low pressure
system will develop along a cold front draped over the Southeast mid
to late week. This feature will then lift northeastward, moving off
of the Northeast or Mid-Atlantic coast Thursday night. The cold
front attached to this system will approach the local area through
the period. It will be weakening as it nears the area, bringing
additional showers and storms. Then, lifts back northward into next
weekend as a warm front.
Wednesday looks to be a wet day, with the frontal passage bringing
PoPs up to 60-70% and a chance for some lightning storms. Given the
expected weakening trend, organized severe storms are not forecast
at this time. A few showers will linger on Thursday. Then,
developing high pressure over the western Atlantic will help lift
the previous front northward as a warm front, increasing
temperatures and slightly increasing moisture. However, the end of
the work week looks to be dry, before yet another cold front
approaches the area Saturday.
A warming trend is forecast through the period, with highs in the
upper 70s to lower 80s on Wednesday warming into the mid to upper
80s by Saturday, as winds veer southwesterly. Should these
temperatures hold, they would be up to around 10 degrees above
normal for early March. Overnight lows will also be increasing, with
lower to mid-60s Wednesday night becoming mid to upper 60s by
Saturday morning.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 62 76 61 75 / 60 50 10 10
MCO 65 81 64 81 / 50 60 10 30
MLB 65 78 63 77 / 50 50 20 30
VRB 64 80 63 80 / 50 50 20 30
LEE 63 79 62 80 / 60 60 10 20
SFB 64 80 63 80 / 60 50 10 20
ORL 65 80 64 81 / 60 60 10 20
FPR 64 80 63 80 / 50 50 20 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&
$$
SHORT TERM/AVIATION...Tollefsen/Haley
LONG TERM....Sedlock
Area Forecast Discussion
National Weather Service Marquette MI
442 PM EST Sat Mar 2 2024
.KEY MESSAGES...
- For early March, unseasonably warm through the weekend. A
record high maximum temperature was set this afternoon and may
occur again Sunday afternoon, and record high minimum
temperatures may be set for the calendar day of March 3 and 4.
- Locally heavy precip possible late Monday into Monday night
with thunderstorms possible east and snow/sleet mixing in
west-central.
- Above normal temperatures continue through next week, although
not as warm as this weekend.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 247 PM EST Sat Mar 2 2024
Water vapor imagery and RAP analysis show a deep mid-level trof
moving onshore over the western U.S. with lower amplitude ridging
downstream across the central and eastern U.S. into se Canada.
Shortwave moving across Hudson Bay has pushed an associated cold
front out over Lake Superior today, but there is no pcpn with it due
to dry low to mid-level air mass over the area. With only high
clouds spreading into Upper MI, it`s a warm aftn for early Mar.
Current readings are in the 50s F across much of the w half of Upper
MI, in record territory. Over the e, southerly flow off of Lake MI
is holding temps down, ranging from the lwr 40s near Lake MI to
around 50F near Lake Superior. Most locations will see temps rise a
few more degrees this aftn, but weakening pres gradient and stalling
out frontal boundary will allow winds to take on an onshore
component across w to n central Upper MI, resulting in temps falling
back a bit.
A strong shortwave will emerge from the western trof tonight,
reaching eastern WY/MT by 12z Sun. Associated low 990s mb sfc low
will track out along the SD/NE border into se SD by sunrise. Btwn
this low and high pres ridging over the Lwr Great Lakes, the
tightening pres gradient will lead to increasing se winds tonight.
However, nocturnal inversion further strengthened by waa will lead
to most of the wind increase occuring aloft, but some gustiness will
develop in high terrain closer to Lake Superior down thru some of
the areas that see downsloping with se winds. Min temps will be held
up due to the winds with lowest temps only around freezing across
the s central, e and also along the e side of the Keweenaw. Temps
will range up to around 40F far w. These readings will be in record
high min temp territory. With temps settling toward freezing and sse
upslope winds eventually advecting dwpts slightly higher than the
air temps, low stratus seems likely to develop across central Upper
MI late in the night.
&&
.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 435 PM EST Sat Mar 2 2024
A negatively-tilted shortwave pivots across the Northern Plains and
into southern Manitoba Sunday evening. An associated surface
low deepens to a sub-1000 mb low near Lake Winnipeg Sunday
night. Warm air advection increases on Sunday as a ~60 kt 850 mb
low level jet shifts east across the area. This intense warm
air advection regime results in a strong boundary layer
inversion that prevents the strongest winds from mixing to the
surface. This inversion may be further enhanced by low level
stratus streaming off Lake MI with some upslope drizzle
possible. For now I kept drizzle mentions confined to Sunday
morning when even the GFS shows an area of low stratus, but NAM
guidance is much more aggressive with low level saturation and
drizzle potential. Other CAMs included in the HREF also show a
plume of stratus developing off Lake Michigan during the
afternoon as dew points increase above water temperatures.
Overall, didn`t make major changes to the going wind forecast
with southerly gusts to 25-35mph on Sunday, highest along the
Lake Superior shoreline.
Temperatures are also tricky on Sunday due to uncertainty in
cloudiness and mixing, but wouldn`t be surprised if theres >20F
difference between the warmest and coolest spots Sunday afternoon.
Temps warming into the 60s seem likely across the western 1/3 of the
UP with temps possibly struggling to warm into the 40s along the
Lake MI shoreline. Temperature struggles continue Sunday night as a
weak cold front moves into the area late. Ahead of the front, temps
stay in the 40s/50s with the front moving over the western UP just
before midnight then reaching the eastern UP around sunrise.
Isolated showers and perhaps a few rumbles of thunder accompany the
FroPa with clouds likely scattering out behind the front. This could
allow for a brief period of efficient radiational cooling to below
freezing at higher elevations leading up to sunrise on Monday.
On Monday, the right entrance of a 130+kt 250 mb jet streak from MN
to James Bay lead to upper diffluence across the area. In response a
weak surface low pressure tracks northeast along the frontal
boundary draped across the area Sunday night. This will support a
band of postfrontal rain developing across the area during the day
Monday, particularly across the eastern UP. This rain will shift out
of the area during Monday night, with a potential for some snow to
mix in with rain on the western edge of the band. It is noteworthy
that the frontogenesis is strong in some of the guidance, with PWATS
increasing to near an inch, so an area of steadier, heavier rainfall
rates is increasingly likely. The grand ensemble has chances of more
than 1/2 inch of QPF increasing to around 50% across the east. P-
type issues also appear likely Monday night across west-central UP
where sleet/snow will probably mix with rain before ending Monday
night.
Dry weather is looking likely Tuesday through Thursday with weak
ridging over the area in the wake of the exiting system. Late week,
a trough will shift out of the western U.S. into the central U.S.
There is high spread in the evolution of this feature, but that`s
not surprising at this time range. For now, a small number of the
ensemble members bring in our next chances for precipitation Friday
into the weekend, with soundings turning cold enough for snow
overnight and a rain/snow mix during the daytime.
&&
.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1252 PM EST Sat Mar 2 2024
Under a dry air mass, VFR will prevail into this evening at
IWD/CMX/SAW. Then tonight, upslope sse winds will eventually lead to
stratus/IFR cigs developing over central Upper MI late in the night,
including at SAW. As the stratus expands, IFR should develop Sun
morning at CMX for at least a couple of hrs. Downslope nature of the
sse winds at IWD will result in MVFR cigs developing at that
terminal during Sun morning. Tightening pres gradient tonight will
set the stage for LLWS to develop at all terminals overnight as
nocturnal inversion holds sfc winds down. LLWS will continue thru
the end of the fcst period though sfc winds will increase and become
gusty to at least 20kt.
&&
.MARINE...
Issued at 435 PM EST Sat Mar 2 2024
Light east-northeast winds continue through the afternoon will also
turn to the NE across western Lake Superior and SE across eastern
Lake Superior by evening. Winds will increase lakewide tonight into
Sunday as low pressure lifts from the Dakotas to southern Manitoba.
While ESE wind gusts will generally be 20-25kt over western Lake
Superior, across the eastern lake, expect S/SE winds to 30 knots.
Internal probabilistic guidance indicates a 30-50% chance for low
end gales to 35 knots across eastern Lake Superior. Given the strong
stability developing as warmer air moves over the cold lake waters,
gale gusts would occur at high obs platforms. Winds should diminish
behind the weak cold front sweeping across Lake Superior Sunday
night with light winds continuing into Monday night. Northwest gusts
become elevated again midweek, at around 20-25 knots, but fall below
20 knots again Thursday.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
Small Craft Advisory until 1 AM EST /midnight CST/ Sunday for
LSZ240-241.
Small Craft Advisory from 7 PM EST /6 PM CST/ Sunday to 7 AM
EST /6 AM CST/ Monday for LSZ240>243.
Small Craft Advisory from 1 AM Sunday to 7 AM EST Monday for
LSZ244-245.
Small Craft Advisory from 7 AM Sunday to 1 AM EST Monday for
LSZ246>251.
Lake Michigan...
Small Craft Advisory from 10 AM Sunday to 1 AM EST Monday for
LMZ221.
Small Craft Advisory from 1 PM Sunday to 7 AM EST Monday for
LMZ248.
Small Craft Advisory until 10 AM EST Sunday for LMZ250.
Gale Warning from 10 AM to 7 PM EST Sunday for LMZ250.
&&
$$
SHORT TERM...Rolfson
LONG TERM...EK/LC
AVIATION...Rolfson
MARINE...EK/LC
Area Forecast Discussion
National Weather Service Omaha/Valley NE
544 PM CST Sat Mar 2 2024
.KEY MESSAGES...
- Very high to locally extreme fire danger Sunday. A Fire
Weather Watch is in effect for portions of southeast NE and
southwest IA.
- Continued above-normal temperatures through the middle of next
week. Then, turning cooler with a chance of precipitation from
Wednesday into Saturday. Best precipitation chances (50-70%)
are Thursday and Thursday night.
- There`s a 10-30% chance of plowable snow in northeast NE
Thursday night into Friday morning.
&&
.DISCUSSION...
Issued at 334 PM CST Sat Mar 2 2024
Tonight through Sunday night:
A potent shortwave and associated mid/upper-level jet streaks
currently moving through the Sierra Nevada into the Great Basin are
forecast to accelerate northeast through the northern Plains and mid-
MO Valley Sunday. That upper-air system will be attended by a
surface cold front, which will move through the forecast area
tomorrow. The 12z models now seem to have a good handle on that
boundary with it`s movement similar to prior runs.
A 40-50 kt nocturnal low-level jet is forecast to develop across the
mid/lower-MO Valley tonight, which should support some degree of
boundary-layer mixing with mild overnight lows in the 40s and 50s.
In fact, there is a good chance that new record low maximums will be
set at Norfolk and Lincoln (40/1974 and 43/1905, respectively). It
will be close at Omaha (49/1983).
Winds will begin to veer to westerly Sunday morning ahead of the
front with a considerably drier low-level air mass being
advected into the region from the west. By afternoon, the
combination of the dry advection, increased vertical mixing, and
temperatures warming into the 70s will result in relative
humidity values falling into the 12-17% range. At the same time,
the stronger surface winds are forecast to shift east into IA
in MO along the eastward-migrating low-level jet. So, while
current fuel status and humidity will be quite favorable for
wildfire growth across much of the area, sufficiently strong
wind speeds (wildfire spread component) for Red Flag conditions
remain uncertain. That notion is supported by 12z HREF joint
probabilities of Red Flag criteria (RH < 20% and wind speed > 20
mph), which indicate generally less than a 20% chance of
occurrence tomorrow afternoon. However, using RAP forecast
soundings as a worst-case scenario, portions of southeast NE and
southwest IA will have sufficiently strong winds to warrant the
issuance of a Red Flag Warning. Given the mixed model signals,
we have opted to issue a Fire Weather Watch for portions of
southeast NE and southwest IA where the stronger winds are most
probable.
The models continue to advertise the potential for some light
precipitation Sunday night into Monday morning, aided by ascent from
a frontal wave tracking from northeast KS into northwest MO.
However, forecast soundings suggest that considerable top-down
saturation will be necessary for precipitation to reach the
surface. For now, the forecast will indicate a chance of
sprinkles and/or flurries Sunday night with the better
precipitation potential shifting east of the area by Monday
morning.
Monday and Tuesday:
A surface ridge axis will build into the mid-MO Valley early next
week with slightly cooler, but still above-normal daytime
temperatures in the 50s and 60s. Surface winds are expected to
be relatively light both days, which should mitigate the
wildfire threat.
Wednesday through Saturday:
Despite slight differences in timing and amplitude, the 12z global
ensembles are in reasonably good agreement in the progression of a
midlevel trough from the western U.S. Wednesday into the Great
Plains on Thursday into Friday. This forecast update will indicate a
chance of precipitation from Wednesday into Saturday with the
highest PoPs (50-70%) occurring Thursday and Thursday evening. The
12z WPC SuperEnsemble indicates a 40-70% chance of > 0.5" storm-
total liquid through Saturday morning, so it appears that at least
some locations will receive meaningful precipitation. Furthermore,
WPC is highlighting portions of northeast NE in a 10-30% chance of >
0.25" liquid equivalent snowfall (i.e., 2-2.5" accumulations)
Thursday night into Friday morning, so that`s something we will be
monitoring.
In regard to temperatures, the forecast will indicate highs in the
50s and 60s Wednesday falling into mainly the 40s by Friday and
Saturday.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 544 PM CST Sat Mar 2 2024
Winds will bring the greatest aviation impact through the TAF
period. South to southeast surface winds 12-20 knots with gusts
25-30kt continue early this evening. Gustiness will diminish
slightly with atmospheric decoupling. Low level wind shear is
expected to develop between 03/04-06Z at all three TAF sites up
to 2000ft AGL 45-50kts, and will diminish 03/12z-15z. As frontal
system moves through the area, surface winds will veer from
south to southeast to west then northwesterly and gustiness will
diminish.
VFR ceilings are expected through the TAF period.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...Fire Weather Watch from Sunday morning through Sunday
afternoon for NEZ067-068-090>093.
IA...Fire Weather Watch from Sunday morning through Sunday
afternoon for IAZ069-079-080-090-091.
&&
$$
DISCUSSION...Mead
AVIATION...Fortin
Area Forecast Discussion
National Weather Service Sacramento CA
117 PM PST Sat Mar 2 2024
.Synopsis...
Impacts from a major winter storm persist today into Sunday across
interior NorCal. After a very brief reprieve early Monday, the next
system arrives Monday afternoon, bringing additional periods of
moderate to heavy mountain snow and gusty winds through early
Wednesday, with some light snowfall accumulations into the Upper
foothills possible on Monday. A stretch of quieter and more
seasonable weather is then expected late week into next weekend.
&&
.Discussion...today through Wednesday.
Key points for the weekend storm:
*BLIZZARD CONDITIONS persist today into Sunday morning along the
Sierra. Moderate to heavy snow through today becomes heavy snow
(snowfall rates up to 2+" per hour) late this afternoon into the
overnight hours. Additional snowfall totals of 2 to 4 feet above
5000 feet, with up to an additional foot of snow above 3000 feet
through Sunday.
*Gusty southwesterly winds to 30 to 45 mph over the Sierra, with
gusts 20 to 25 mph elsewhere. This, in conjunction with heavy
snowfall, will continue to result in periods of near zero visibility
over the Sierra.
*Snow levels around 3000` through today lower to 1500` to 2500` by
Sunday morning (lowest in the northern Sacramento Valley), with
light accumulations possible at low elevations.
*Mountain travel will continue to be extremely dangerous to
impossible through today and likely into Sunday as well.
*Isolated thunderstorms possible this afternoon/evening throughout
the Valley and adjacent foothills locations. Brief heavy rainfall,
small hail, gusty winds, lightning, and isolated instances of funnel
clouds will all be possible with any storms that do develop.
---------------------------------------------------------------
As of early this afternoon, moderate to heavy snow is persisting
over the Sierra, with isolated showers elsewhere throughout the
Valley and foothills. This isolated shower activity is expected to
become more numerous through the afternoon as another plume of
moisture arrives with this system. With a brief window of clearing
beginning to work its way into the southern Sacramento and northern
San Joaquin Valleys, latest RAP mesoanalysis is indicating the
presence of some instability, around 250-500 J/kg, throughout the
Valley at this time. As a result, some isolated thunderstorm
activity will be possible through the afternoon and evening hours.
While directional shear is nominal at best, strong speed shear
(~20kts 0-1 km shear and 100+ kts 0-6 km shear) is present this
afternoon, along with an offshore jet streak placing interior NorCal
within the left exit region of the jet. This may result in a few
stronger updrafts able to produce some small hail and possibly a few
isolated instances of funnel clouds as well.
While moderate to occasionally heavy snow prevails over the Sierra
this afternoon, as this activity travels eastward toward the Sierra,
the convective and upslope enhanced elements are expected to result
in additional heavy snow late this afternoon into the overnight
hours. Snowfall rates of 2+" per hour will be possible at times with
snow levels lowering from around 3000` today down to 1500` to 2500`
by Sunday morning. Moderate snow is then expected to linger through
Sunday, with a brief period of lighter snow showers on Monday
morning.
Despite this seemingly downward trend in impacts, the next system is
expected to arrive by Monday afternoon. Lower individual impacts are
anticipated with this system, but with the limited time between
systems, overall impacts may be compounded, especially over the
mountains. Isolated, light showers are expected in the Valley, with
moderate to occasionally heavy snowfall expected over the Sierra
from Monday evening through Tuesday. Additional periods of moderate
snowfall are also expected over the Coastal Range and northern
Shasta County through Monday. Gusty south-southeasterly winds look
to increase with this system late Monday through Tuesday as well.
Strongest gusts to 45 mph will be possible over the Sierra, with
gusts to 35 mph across the northern Sacramento Valley, and gusts 20
to 25 mph elsewhere.
Snow levels will start off somewhat low on Monday, in the 2000` to
3000` range, before rising to 3000` to 4000` Tuesday into Wednesday.
These initially lower snow levels will allow for some light
accumulations across the Upper foothills on Monday. Otherwise, an
additional 1 to 3 feet of snowfall will be possible above 4500 feet
along the Sierra through early Wednesday morning, with an additional
1 to 2 feet possible over the highest elevations of the Coastal
Range and northern Shasta county. Lingering snow showers over the
Sierra will then be the only impact remaining by midday Wednesday,
as a quieter weather period begins to settle in mid to late week.
*Mountain travel is HIGHLY discouraged while the warnings are in
effect!*
&&
.EXTENDED DISCUSSION (Wednesday THROUGH Saturday)...
Cluster analysis and ensembles are showing the secondary trough
we`re expecting moving over and out of the area on Wednesday and
Thursday. While the mountains may see lingering snowfall into early
Thursday morning, snow levels will continue to rise, and snow rates
will diminish over this time. Overall, this secondary system will
have less total impact than the current storm, but by late Wednesday
higher elevations can still expect to see an additional foot or more
of snow (50-85% probability above 4500 ft). Precipitation outside of
the mountains, foothills, and northern Sacramento Valley looks to
remain minimal. Currently, the NBM is projecting a 25 to 30%
probability of exceeding half an inch in the northern San Joaquin
Valley by late Wednesday, and a 50-70% probability in the southern
and middle portions of the Sacramento Valley. The northern
Sacramento Valley, as well as areas in the northern foothills and
mountains show a 50 to 85% probability of an inch or more of
precipitation.
There is generally good ensemble agreement on upper level ridging
building over the area late in the week, bringing a respite from the
active weather we have been experiencing. Weather during this time
will be drier and warmer than it has been in recent days. Looking
past the extended period, there is some indication of another
unsettled weather pattern occurring early next week, though
cluster analysis shows some disagreement between ensembles on when
exactly that pattern might occur and how strong it will be. //SP
&&
.AVIATION...
In the Central Valley, periods of MVFR/IFR with showers over the
next 24 hours. Periods of southerly surface wind 12-20 kts with
local gusts to around 25 knots possible thru 03z Sunday. Isolated
thunderstorms possible through 03z Sun in the Valley, with low
confidence on these impacting any TAF sites. Over foothills and
mountains, widespread MVFR/IFR with areas of LIFR in rain/snow.
Snow levels around 3000 feet today, decreasing to 1500-2500 feet
Sunday morning. Southwest to westerly gusts to 30-45 kts across
mountains over the next 24 hours.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 10 AM PST Sunday for Burney Basin /
Eastern Shasta County-Mountains Southwestern Shasta County to
Western Colusa County-Shasta Lake Area / Northern Shasta County.
Blizzard Warning until 10 AM PST Sunday for Motherlode-Northeast
Foothills/Sacramento Valley-West Slope Northern Sierra Nevada-
Western Plumas County/Lassen Park.
&&
$$