Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/13/22
Area Forecast Discussion
National Weather Service La Crosse WI
611 PM CDT Tue Apr 12 2022
.DISCUSSION...(This evening through Tuesday)
Issued at 254 PM CDT Tue Apr 12 2022
Key Messages:
- Gusty winds/scattered storms late this afternoon with hail
potential
- Severe weather risk this evening/tonight, highest west of the
MS River
- Strong, gusty winds likely on Thursday
Tonight: Severe Storm Risk
The main focus late this afternoon and tonight remains on severe
storm potential. Preceding the surface low, gusty S/SE winds have
developed in conjunction with strengthening low-level flow. Gusts
have locally reached 45 to 50 mph in some areas so did issue a short
wind advisory for areas west of the MS River. Additionally, showers
and storms will continue to translate northeast with a slug of
strong mid-level warm advection on the edge of the elevated
instability axis through late afternoon. With the steepening mid-
level lapse rates, any storms may produce some hail, with a few
storms likely to produce hail to 1"+.
Heading into this evening, the filling surface low will lift from
eastern NE into southern MN with its associated warm front lifting
north into the area. Despite the extensive low clouds north of
the boundary, an airmass change will occur as the boundary lifts
north with increasing dew points/temps. While a plume of elevated
instability will lift north through the afternoon/evening as lapse
rates steepen aloft, a pool of MLCAPE will spread north and east
more gradually and weaken ahead of the low/cold front this
evening/tonight.
After the initial warm advection storms, the general expectation is
for storms to develop late this afternoon closer to the triple point
in western IA/eastern NE/southwest MN spreading east through evening
and likely organizing into a linear band of storms by the time they
approach. HREF UH paintballs show clustering across western
IA/southern MN during the evening, with storms approaching the local
area by late evening (10-11 pm), weakening as they track east
into WI overnight. Scattered elevated storms also could form by
early to mid evening near the warm front in northern IA/southern
MN/northern WI as the low-level jet strengthens posing primarily a
hail threat given the strong low-level stability/capping in the
warm sector.
There remains some uncertainty in the evolution/strength of the
storms late this evening. RAP soundings show fairly stable/capped
low-levels despite the moistening/increasing MLCAPE through the
evening. The window for surface-based storms looks quite narrow,
focused right ahead of the approaching front. This is when the risk
for damaging winds or an isolated tornado would be maximized with
any bowing segments/mesovortices, especially across far
southwestern counties where HREF/RAP fields show SBCAPE/MLCAPE
maximized over 1000 J/kg. Some severe weather risk could persist
into western WI, although buoyancy will be on the decline
overnight as storms move into this area. Despite the impressive
low-level shear, the low-level thermodynamic profiles and late
evening/overnight timing decreases confidence in the overall
threat, especially with eastward extent, but it will be an evening
to keep on eye on trends as storms begin to develop, given the
rapid airmass change as warm, moist air advects north.
Wednesday/Wednesday Night
Upper level closed low over the Northern Plains States lifts slowly
northeast into northern Minnesota Wednesday into Thursday. Several
pieces of energy rotate around the closed upper level low into the
Upper Mississippi River valley. Main surface front passes across the
forecast area early Wednesday morning. This will push the deeper
moisture transport/east of the forecast area during the day
Wednesday. However...with pieces of energy rotating around the upper
closed low...showers and potentially a few thunderstorms will linger
mainly along and east of the Mississippi River Wednesday afternoon.
Cooler temperatures will advect in behind the surface front and
allow for temperatures to remain nearly steady or fall into the
middle 40s to lower 50s by middle of Wednesday afternoon.
Thursday
Focus turns to the windy conditions across the forecast area
Thursday. Combination of pressure gradient tightening and winds
aloft mixing down to the surface will produce windy conditions
across the forecast area. Both of the NAM/GFS Bufkit soundings show
45 to 50 knots at the top of the mixed layer. Expect wind gusts to
be 40 to 50 miles per hour. Along with the windy
conditions...rain/snow showers will develop Thursday afternoon and
mainly over the northern half of the forecast area.
Friday through Tuesday
Main forecast concerns Friday through Tuesday are precipitation
chances Sunday into Monday. Upper level closed low/trough slowly
pulls east of the Upper Mississippi River valley and another
shortwave trough will track into the Northern Plains States this
weekend. The 12.12z deterministic GFS/ECMWF show some differences on
the strength with the shortwave trough. This will have impacts on
timing of precipitation chances. Depending on temperatures Sunday
into Monday...light snow will continue to be possible across much of
the forecast area. The deterministic models continue to show cooler
airmass filtering in with the shortwave trough and into early next
week. The 12.12z GFS/ECMWF indicate 925mb temperatures around 0
degrees celsius to minus 4 degrees celsius through the forecast
period. Temperatures will remain well below normal...with highs
mainly in the 40s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 611 PM CDT Tue Apr 12 2022
The next round of convection is quickly developing over northern
Iowa and is expected to expand northeast into the area this
evening. Current expectations are that thunderstorms will be
possible at both sites from mid-evening through about midnight or
so with MVFR/IFR conditions. Behind the storms, lingering
showers/rain for awhile overnight with what should be VFR ceilings
before the ceilings go back down to MVFR late tonight as the
showers/rain come to an end. The winds will be gusty out of the
southeast this evening coming around to the south/southwest
overnight before going west once the front goes through early
Wednesday morning.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
DISCUSSION...DTJ/JM
AVIATION...04
Area Forecast Discussion...CORRECTED
National Weather Service Brownsville TX
709 PM CDT Tue Apr 12 2022
.DISCUSSION...Updated for latest aviation discussion below.
&&
.AVIATION...Satellite and radar images as well as surface
observations indicate scattered showers and thunderstorms across
portions of northeast Mexico early this evening with high level
clouds from the storms moving across southern and eastern portions
of deep south Texas (mainly Cameron, Willacy and Hidalgo
counties). In addition...low to mid level clouds continue across
portions of the Rio Grande Valley. Ceilings were near 1400ft at
KPIL to near 3000ft at KMFE. Visibilities were near 6SM with haze
at KBRO. Expect MVFR conditions to prevail across the Rio Grande
Valley tonight into early Wednesday morning as a 500mb shortwave
trough across northeast Mexico moves eastward tonight providing an
increase in low to mid level moisture across the area. This will
provide showers or thunderstorms in the vicinity of local
aerodromes this evening. In addition...low clouds and haze will
reduce ceilings/visibilities across the RGV tonight. Last but not
least...a strong low level jet along the lower Texas coast will
provide some low level wind shear across portions of the Rio
Grande Valley late tonight into early Wed morning as the surface
winds decouple with the stronger winds aloft with the loss of
diurnal heating.
&&
.PREV DISCUSSION... /issued 311 PM CDT Tue Apr 12 2022/
SHORT TERM (Now through Wednesday Night): First off, congrats to
those who picked up a little rain this morning! It wasn`t much
(less than 0.05" everywhere) , but we`ll take any thing we can get
after a month or more of no rain in a number of locations. There
were also a few reports of pea-sized hail within the stronger
storms this morning, which makes sense given the dry mid-levels
and steep mid- level lapse rates over 8.5 C/km that were shown on
the 12Z sounding at KBRO this morning.
Aloft, an H5 shortwave is currently moving over northern Mexico with
another impulse of energy coming off the Sierra Madre Oriental
already (as of 2:45 PM CDT) sparking some showers and storms near
Monterrey, Mexico. As the impulse moves closer to the County Warning
Area (CWA) tonight, it should help sustain those showers and storms
as they come off the mountains. A few wrinkles to that is a stout
CAP (temperature inversion) between 925 & 850mb along with the very
dry mid-levels indicated on the special 18Z sounding we did for
PERiLS. These could limit how widespread the showers and
thunderstorms could be as they near the CWA later tonight. That
said, I leaned pretty hard on the Convection Allowing Models (CAMs),
which did handle this morning`s rain/convection fairly well, for
tonight`s forecast. As it stands now, the best chance for rain this
evening will be in the Rio Grande Valley. The current timing has
showers/storms entering around 5-6PM CDT for Starr County and an
hour or so later for the rest of the Valley as everything lifts in
from the southwest. The Storm Prediction Center (SPC) has placed
areas west of I-69C under a Marginal Risk of severe weather with
their latest update. The greatest threats for severe storms will
come from hail and damaging winds. Areas east of I-69C could see
stronger storms this evening as well, just confidence is a bit
higher out west.
Additionally, the last several runs of the HRRR have shown the
potential for a wake low forming behind the cluster of showers and
storms it has moving through the area. This is due to the dry mid-
levels in place evaporating the rain aloft, which then cools the air
in the mid-levels and allows it to rush to the surface and produce
strong, gusty winds. Not super confident in this, but wanted to
mention it as a possibility.
That`s all tonight... Wednesday will see a dry line advance westward
in the afternoon ahead of a cold front that will eventually catch up
to it. Areas west of the dry line, which should make it to roughly
the I-69E/US-77 corridor, could see temperatures climb above 100
degrees while those near the coast "only" top out in the middle to
upper 90s. This is a similar set up to last Wednesday, but some
morning clouds and slightly lower 850mb temperatures *should* keep
areas from spiking too high. Key word there... Should.
The cold front stalls along the coast Wednesday night and will get
pushed inland as the night progresses. So, while overnight
temperatures are expected to be a bit cooler Wendesday night,
they`ll still drop to near normal.
LONG TERM (Wednesday Night through Tuesday):The northern jet stream
retreats northward for the middle and latter half of the week as
northern edge of the Subtropical Ridge builds over Mexico edging
into South Texas. Two storms systems pass along and just south of
the Canadian border one the end of the work week and a second more
southern one next Monday and Tuesday. This in turn will result in
an overall reduction in the wind speeds with a more gentle to
moderate breeze and higher relative humidity to reduce the fire
danger for the long term. The first mid-level low pressure system
looks to have enough energy to push a trailing cold front into the
region Thursday but lifting back north Friday. Low level moisture
and increasing pwats in the 1.7-1.9 inch range may lead to some
isolated showers. NBM remains dry in this period while the GFS/EC
still show limited QPF. Confidence is low but will leave the
current low end pops in for Friday morning and add some in Thu
night for good measure with the front draped over the region. The
weekend looks fair with the subtropical ridge reaching its apex
and a light to moderate Gulf breeze. Highs Thu- Sunday in the 80s
to mid 90s and possibly a few lower 100s far west on the weekend.
Lows remain mild in the 60s to around 70 along the Rio Grande.
Next week a stronger mid-level low moves across the Great Lakes and
Midwest. A stronger front works its way south but there is uncertainty
if it moves through the RGV. ECMWF remains strongest with the
front with the GFS lagging on it southward push. There is a lot of
uncertainty on how this front plays out with the overall chance
of rain. NBM indicates rain chances increasing Monday and
lingering Tuesday while the 12/12Z GFS and 11/00Z ECMWF are not
in total agreement with this. Moisture does pool and increase
around the front so will go with the low end pops that the NBM
suggest for now. Monday`s highs will be in the upper 80s and 90s
with limited cooling in the low to mid 80s Tuesday if the front
makes it into the region.
MARINE (Now through Wednesday Night)...Adverse marine conditions
continue along the Lower Texas Coast for much of the period.
Breezy to gusty conditions are expected on the Laguna Madre the
rest of the afternoon through 6 AM CDT Wednesday. Meanwhile, seas
on the Gulf waters remain very high with the latest observation at
Buoy 42020 showing seas of around 7 feet. Elevated seas and
occasional winds above 20 knots are expected through Wednesday
night, where the Small Craft Advisory has been extended now until
1 AM CDT Thursday. Also, a complex of showers and thunderstorms
are expected this evening into the overnight hours. Gusty winds
(in excess of 35 knots), lightning, and small hail will all be
possible within any of the thunderstorms along the Lower Texas
Coastal waters tonight.
Thursday through Sunday...Fair marine conditions are expected
late this week and over the weekend. A weak cold front works into
the Lower Texas Gulf waters Thursday before returning north
Friday. Moderate northeast to east winds may be strong enough to
warrant short duration Small Craft Advisories Thursday with more
tranquil conditions Friday. Weak high pressure builds across the
eastern Gulf and Friday`s retreating front pulls up stationary
across the Gulf South maintaining a light onshore flow for the
lower coast. Seas will tend to be on the moderate to low side.
FIRE WEATHER (Wednesday): Critical fire weather conditions are
expected Wednesday due to a dry line/cold front combo that will be
pushing in from the west. This will drop relative humidity values
to between 8 to 25 percent for all of the Brush Country, Rio
Grand Plains, and the Mid/Upper Rio Grande Valley and western
portions of the Brooks/Kenedy Ranches in the afternoon. 20-foot
winds are forecast to increase and start coming out of the
northwest behind the dry line.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 74 94 69 82 / 40 0 0 10
BROWNSVILLE 75 98 71 87 / 40 0 0 10
HARLINGEN 74 100 68 87 / 40 0 0 10
MCALLEN 74 103 69 92 / 40 0 0 10
RIO GRANDE CITY 74 104 68 95 / 20 0 0 0
SOUTH PADRE ISLAND 73 82 70 75 / 40 0 0 10
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk through Wednesday evening for TXZ451-454-
455.
Red Flag Warning from noon to 7 PM CDT Wednesday for TXZ248>250-
252-253-353.
GM...Small Craft Advisory until 6 AM CDT Wednesday for GMZ130-132-135.
Small Craft Advisory until 1 AM CDT Thursday for GMZ150-155-170-
175.
&&
$$
This product is also available on the web at:
https://weather.gov/rgv
61-Castillo/69-Farris/67-Mejia
Area Forecast Discussion
National Weather Service Corpus Christi TX
1007 PM CDT Tue Apr 12 2022
.MARINE...
The HRRR and RAP indicated winds increasing through midnight with
gusts to gale force. Buoy020 reported gusts to 35 knots and MSAS
analysis indicated a meso-high has developed in response to
convection earlier in the evening near BROs area. Therefore, have
gone with a Gale Warning through 5 AM Wed for frequent gusts to
gale force. This includes the nearshore waters south of Port
Aransas and the offshore waters out to 60NM.
&&
.PREV DISCUSSION... /Issued 657 PM CDT Tue Apr 12 2022/
AVIATION...
MVFR conditions due to CIGs and patchy light fog are expected to
develop across the eastern TAF sites through the evening then
spreading west with brief MVFR conditions across LRD and COT
overnight into early Wed morning. Brief IFR CIGs are possible
across VCT toward early Wednesday morning. A low level jet will
strengthen to 40-45 knots overnight, but elevated surface winds
across most areas should preclude LLWS, except COT where surface
winds are expected to be lowest. A dryline will move east through
the day Wed resulting in winds shifting to the west then
northwest as the dryline approaches the coast. The dryline is
expected to retreat westward by late afternoon with winds along
the coast clocking back around to the east. Wind gusts to around 25kt
will be possible beginning mid morning Wed. All TAF sites winds
are expected to be easterly and weaker Wed evening.
PREV DISCUSSION... /Issued 335 PM CDT Tue Apr 12 2022/
SHORT TERM (Tonight through Wednesday Night)...
A look at water vapor imagery this afternoon reveals a shortwave
ejecting out of Mexico. This has led to isolated showers and storms
through the afternoon across the Coastal Plains and Victoria
Crossroads. A few of these storms have been on the stronger side
with small hail being the main threats. Our 18Z sounding hints at
a weakening cap and a substantial amount of instability. This is
also evident by the well defined field of ACCAS moving across the
Coastal Plains. Any additional convection that fires up this
afternoon would have the potential to near severe limits with
large hail and damaging winds the main hazards. With that said,
models continue to show another upper level shortwave rotating
across the region late this afternoon and evening. Another round
of showers and storms are possible as this disturbance moves
through. Recent CAM guidance keeps the bulk of the activity to our
south where the greatest forcing will be. However, the 12Z runs
of the ARW and FV3 showed some activity across our northern
counties this evening. Overall confidence in that solution is not
too high but would not be surprised to see anything develop along
a lingering outflow boundary. Any activity that does develop this
evening looks to push offshore by 03Z.
A low level stratus deck looks to build back in tonight as a ~40 LLJ
ushers moisture across the region. After a mild and breezy night,
the main story on Wednesday will be our critical fire weather
concerns. A dryline will mix across the region on Wednesday ahead of
an approaching cold front and associated upper level trough. It`s
possible we see some isolated showers and potentially a storm or two
ahead of the dryline where low level moisture convergence will be
maximized. Critical fire weather conditions are possible behind the
dryline as it stalls across the Coastal Plains (see fire section for
more). As the dryline begins to retreat back to the west late
Wednesday afternoon, a cold front will pick it up and eventually
stall across the CWA. The boundary will eventually begin to push
back north by Thursday morning.
LONG TERM (Thursday through Tuesday)...
Zonal flow aloft on Thursday will transition to a building mid to
upper level ridge by the weekend. Moisture will begin recovering
through the day on Thursday as a surface high pressure lifts to the
northeast, allowing for the surface flow to gradually become
onshore. Precipitable water values are progged to then increase to
around 1.7 to 1.8 inches on Friday, which combined with lift and
instability provided by a passing weak mid level disturbance could
result in a few showers and/or thunderstorms over the region. Drier
conditions are expected to develop heading into Friday night and
will generally continue through the weekend as ridging then takes a
hold.
Rain chances may return to the forecast early next week as weak
troughing develops aloft while it drags a few more passing
disturbances along. At this time have opted for closely following
the output from the NBM for Monday through Tuesday next week in
terms of precipitation chances, as the mid range models continue to
disagree on the amount of moisture available by then and also on the
possibility of another frontal boundary moving through. With that
said, have capped PoPs at the slight category.
Other than the potential slight chances for rain through the period,
the Extended forecast will feature increasingly warmer temperatures,
particularly over the weekend. Highs on Saturday and Sunday are
forecast to reach into the triple digits for portions of the Brush
Country and Rio Grande Plains, with temperatures in the mid 80s to
mid 90s elsewhere. These very warm temperatures along with high
dewpoints could lead to a few hours of heat indices in the 100-105
range both days. If the aforementioned frontal boundary is able to
push all the way trough the region early next week, then cooler
temperatures may be in the cards for next Tuesday.
MARINE...
Onshore flow has steadily strengthened through the day and will
remain elevated overnight. A Small Craft Advisory remains in
effect for the bays through early tomorrow and through the early
evening hours for the offshore waters. Onshore flow will weaken to
more moderate levels through the day Wednesday. There is a slight
chance for isolated showers and thunderstorms over the waters
through the day tomorrow. Moderate to strong northeast to east wind
is expected to develop again by mid morning Thursday and remain
in place through Thursday night. Winds will shift to the south and
southeast on Friday, with a moderate to at times strong onshore
flow expected through early next week. Slight rain chances will be
possible Friday and then again on Monday.
FIRE WEATHER...
Critical fire weather conditions are expected tomorrow across the
Brush Country as a dryline mixes east. Very dry conditions are
expected to settle in behind the dryline with RH values falling
into the single digits. Although the winds may not specifically
reach Red Flag Warning criteria, fuels are extremely dry and would
easily lead to rapidly fire growth. In addition, the latest suite
of the TFS maps places the Brush County under an Extreme Fire
Danger Rating for Wednesday. The Coastal Plains falls under the
Very High category. With that said, there may need to be an
expansion further east with the RFW depending on how far the
dryline shifts during the day.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 72 95 67 84 68 / 20 10 0 0 10
Victoria 71 93 59 87 65 / 20 20 0 0 10
Laredo 73 100 64 96 68 / 0 0 0 10 10
Alice 71 100 64 89 67 / 10 10 0 0 10
Rockport 72 87 67 81 69 / 20 20 0 0 10
Cotulla 72 100 58 97 68 / 10 0 0 0 0
Kingsville 72 99 66 87 68 / 10 10 0 10 10
Navy Corpus 71 85 69 79 69 / 10 10 0 0 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk through Wednesday evening For the
following zones: Aransas Islands...Calhoun Islands...
Kleberg Islands...Nueces Islands.
Red Flag Warning from noon to 7 PM CDT Wednesday For the
following zones: Duval...Jim Wells...La Salle...Live Oak...
McMullen...Webb.
GM...Small Craft Advisory from 5 AM to 7 PM CDT Wednesday For the
following zones: Coastal waters from Baffin Bay to Port
Aransas out 20 NM...Waters from Baffin Bay to Port Aransas
from 20 to 60 NM...Waters from Port Aransas to Matagorda
Ship Channel from 20 to 60 NM.
Gale Warning until 5 AM CDT Wednesday For the following zones:
Coastal waters from Baffin Bay to Port Aransas out 20 NM...
Waters from Baffin Bay to Port Aransas from 20 to 60 NM...
Waters from Port Aransas to Matagorda Ship Channel from 20
to 60 NM.
Small Craft Advisory until 5 AM CDT Wednesday For the following
zones: Baffin Bay and Upper Laguna Madre...Copano, Aransas,
and Redfish Bays...Corpus Christi and Nueces Bays...San
Antonio, Mesquite, and Espiritu Santo Bays.
Small Craft Advisory until 7 PM CDT Wednesday For the following
zones: Coastal waters from Port Aransas to Matagorda Ship
Channel out 20 NM.
&&
$$
TE/81...SHORT TERM
XX/99...LONG TERM
Area Forecast Discussion
National Weather Service Des Moines IA
659 PM CDT Tue Apr 12 2022
...Updated for the 00z Aviation Discussion...
.SHORT TERM.../Tonight through Wednesday Night/
Issued at 311 PM CDT Tue Apr 12 2022
Forecast Impacts for the week:
...Moderate Risk into Tonight
...Cooler Weather Returns
...Chances for Rain/Snow return into the weekend
Confidence Short Term: Medium to High
Overall the evolution of the system in both a synoptic and mesoscale
space is still on track. The big question that is becoming a bit
more clear is the northern location of the warm front around
initiation time. Previous model runs have placed the front/triple
point across far northwest Iowa (specifically the HRRR/GFS) as
compared to the Euro. Today the HRRR is farther south with the
boundary near 23z to 01z while the GFS is still closer to its
previous forecast and farther north. At 19z, the boundary is just
entering SW Iowa with a large shield of stratus and now elevated
convection over Iowa into MN with the stronger storms into southern
MN. Recent HRRR runs have shown that any stronger convection that
may develop over the north is now more focused nearer the US20
corridor, rather than the IA MN border. With that in mind, the
current moderate risk for that portion of the forecast appears well
placed and the westward extension back into west Iowa remains for
the area of secondary development expected along the dry line in the
evening from 01 to 02z across the west. Without going into great
detail, forcing and shear parameter space is is on the middle to
high end of the spectrum. With SBCAPE over 3200 j/kg into the early
evening along the retreating warm front and 0-1km SRH over 300 to
500 m2/s2 and long hodographs, there remains a potential for
discrete supercells and a strong and relatively longer lived tornado
or two in that area. If storms develop slightly north of the warm
front, then a large hail threat would likely dominate the mode. Any
supercells that develop will move northeast/east with time along or
near the warm front. As the dry line now in central Nebraska will
edge east and fire off a line of storms into our west by 01z. The
line of storms is anticipated to strengthen quickly to severe levels
and then slowly weaken as it moves toward the I35 corridor in
central and southern Iowa. These storms later in the evening will
have a somewhat less potential to be tornadic, but a severe wind
threat and hail threat will continue. The northern portion of the
line may have an opportunity to tap into the strong 0-3km shear and
continue to have a tornado threat through at least the early morning
hours. This area would more likely be along and north of US20. As
the synoptic low drives northeast, a weaker surge of west northwest
winds will move over the region tomorrow with colder air. Lows
tonight will drop to the mid 30s west to the lower 50s east. Highs
tomorrow will be in the 40s to around 50.
&&
.LONG TERM.../Thursday through Tuesday/
Issued at 311 PM CDT Tue Apr 12 2022
Confidence: Medium
The remainder of the forecast will be dominated by dry weather
through Saturday with a chance of rain and snow Sunday. We continue
with northwest flow and cool weather into the remainder of the
extended with little warming. Highs will remain in the 40s and 50s
with cool April highs during the remainder of the forecast.
&&
.AVIATION.../For the 00Z TAFS through 00Z Wednesday evening/
Issued at 642 PM CDT Tue Apr 12 2022
Main aviation concerns continue to be storms and wind, especially
in the next few hours of the TAF cycle. Storms could gust to
severe limits in addition to dropping ceilings and visibilities
into MVFR or even brief periods of IFR. Additionally, low-level
wind shear is expected into the early overnight hours and gusty
winds of the south, shifting to be out of the west to northwest,
will remain into tomorrow behind an approaching cold front.
Storms/showers expected to end west to east during the overnight
hours, roughly between 09-12Z, with VFR conditions returning
gradually to all TAF sites by about mid morning.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...REV
LONG TERM...REV
AVIATION...KCM
Area Forecast Discussion
National Weather Service Quad Cities IA IL
637 PM CDT Tue Apr 12 2022
...AVIATION UPDATE...
.SYNOPSIS...
Issued at 254 PM CDT Tue Apr 12 2022
A warm front is lifting north into the CWA as of 2 PM, and our 18Z
upper air sounding shows this taking place. As forecast, there is a
very steep layer of mid level lapse rates, but though steep, there
is very little moisture within that layer. A strong EML exists above
the lowest thousand feet, which means the impressive shear found
from the surface to 3500 ft is not able to be accessed by updrafts
this afternoon.
&&
.SHORT TERM...(This Evening through Wednesday)
ISSUED AT 254 PM CDT Tue Apr 12 2022
Tonight, the timing of the squall line arrival remains very late in
the evening west to around 6 AM in our Illinois counties. This late
arrival coincides with consistent model data showing waning
instability, decaying storm organization. Strong shear values
continue through early morning which should be something that really
stays going ahead of the front through tomorrow. In case, I find
little reason to deviate from the ongoing high pop forecast in our
northwestern counties around Midnight, then translating east as a
likely pop approaching the Mississippi River, then chance east. QPF
will be relatively low, generally less than 0.25".
I`ll continue to advertise the severe gust potential with the
decaying squall line, but this threat for severe will greatly lower
as the sees increasingly back sheared tilted updrafts with quick
eastward motions resulting in sputtering updraft strength.
Highs Wednesday for most locations will occur between Midnight
and 8 AM, as CAA increases with low stratus in place behind the
decayed line. Another wave of moisture and some MUCAPE will bring
rain and embedded thunder to the area during the day Wednesday. A
cold rain is expected in most spots, but the far east could see a
downdraft with winds over 50 mph, should surface heating early in
the day coincide with secondary wave. Right now, it looks like
precipitation will overspread the entire area during the late
morning, and then gradually end from west to east during the late
afternoon.
Afternoon wind chills in the upper 30s to lower 40s will be found
west of the Mississippi River. Brrr!
.LONG TERM...(Wednesday Night through Tuesday)
ISSUED AT 254 PM CDT Tue Apr 12 2022
Key messages:
1. Windy day on Thursday.
2. Cooler temps through the period.
3. Clipper into the weekend is next chance for QPF across the
area.
Discussion:
Upper level pattern changes from zonal to NW a few times through
the long term period as storm track is north of the area.
Reinforcing shots of cold air keep us on the cooler side of
average as we see highs in the 40s to low 50s. Nighttime temps in
the 30s near freezing may be the more important forecast
parameter as chances for snow or frost/freeze seem to be the main
thing of hazard after Thursday`s winds.
Thursday, guidance continues to have lower wind gusts than earlier
in the week. We are just getting into CAM data, and the NAMnest
continues the sub 40 knot wind gusts and more like a low to mid
30 gust potential. The 12z HRRR has stronger winds than most
guidance across S MN as the upper low moves in, so will need to
keep an eye on this to see which way it trends. My initial guess
is that the HRRR, may be better at gust forecasts for this event
as it usually does a better job with mixing and wind gusts. Still
plenty of time to analyze this threat as we are 40 some hours out
from when it would start.
After this, a clipper that moves across the northern CONUS will
bring a chance for precip late in the weekend. With temperatures
near or below freezing we could see some frozen precip. Confidence
in this occurring is low. We are right on the cusp for
frost/freeze headlines and will keep a close eye on vegetation.
This may be the larger threat after Thursday. Confidence in this
occurring is also low.
&&
.SHORT TERM...(This Evening through Wednesday)
ISSUED AT 254 PM CDT Tue Apr 12 2022
Tonight, the timing of the squall line arrival remains very late in
the evening west to around 6 AM in our Illinois counties. This late
arrival coincides with consistent model data showing waning
instability, decaying storm organization. Strong shear values
continue through early morning which should be something that really
stays going ahead of the front through tomorrow. In case, I find
little reason to deviate from the ongoing high pop forecast in our
northwestern counties around Midnight, then translating east as a
likely pop approaching the Mississippi River, then chance east. QPF
will be relatively low, generally less than 0.25".
I`ll continue to advertise the severe gust potential with the
decaying squall line, but this threat for severe will greatly lower
as the sees increasingly back sheared tilted updrafts with quick
eastward motions resulting in sputtering updraft strength.
Highs Wednesday for most locations will occur between Midnight
and 8 AM, as CAA increases with low stratus in place behind the
decayed line. Another wave of moisture and some MUCAPE will bring
rain and embedded thunder to the area during the day Wednesday. A
cold rain is expected in most spots, but the far east could see a
downdraft with winds over 50 mph, should surface heating early in
the day coincide with secondary wave. Right now, it looks like
precipitation will overspread the entire area during the late
morning, and then gradually end from west to east during the late
afternoon.
Afternoon wind chills in the upper 30s to lower 40s will be found
west of the Mississippi River. Brrr!
.LONG TERM...(Wednesday Night through Tuesday)
ISSUED AT 254 PM CDT Tue Apr 12 2022
Key messages:
1. Windy day on Thursday.
2. Cooler temps through the period.
3. Clipper into the weekend is next chance for QPF across the
area.
Discussion:
Upper level pattern changes from zonal to NW a few times through
the long term period as storm track is north of the area.
Reinforcing shots of cold air keep us on the cooler side of
average as we see highs in the 40s to low 50s. Nighttime temps in
the 30s near freezing may be the more important forecast
parameter as chances for snow or frost/freeze seem to be the main
thing of hazard after Thursday`s winds.
Thursday, guidance continues to have lower wind gusts than earlier
in the week. We are just getting into CAM data, and the NAMnest
continues the sub 40 knot wind gusts and more like a low to mid
30 gust potential. The 12z HRRR has stronger winds than most
guidance across S MN as the upper low moves in, so will need to
keep an eye on this to see which way it trends. My initial guess
is that the HRRR, may be better at gust forecasts for this event
as it usually does a better job with mixing and wind gusts. Still
plenty of time to analyze this threat as we are 40 some hours out
from when it would start.
After this, a clipper that moves across the northern CONUS will
bring a chance for precip late in the weekend. With temperatures
near or below freezing we could see some frozen precip. Confidence
in this occurring is low. We are right on the cusp for
frost/freeze headlines and will keep a close eye on vegetation.
This may be the larger threat after Thursday. Confidence in this
occurring is also low.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening)
ISSUED AT 629 PM CDT Tue Apr 12 2022
Low-level wind shear of 50+ kts and MVFR clouds are expected
overnight, along with a weakening line of showers and
thunderstorms arriving late. Periods of IFR are possible
especially in pockets of brief moderate/heavy rain. Gusty S to SSE
winds will continue into early Wednesday AM before switching to
the WNW behind a cold front. Another round of rain is expected
from around midday Wednesday through the afternoon, which could
be moderate to briefly heavy at times at BRL and MLI.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...Ervin
SHORT TERM...Ervin
LONG TERM...Gibbs
AVIATION...Uttech
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
752 PM CDT Tue Apr 12 2022
.UPDATE...
Severe thunderstorms have moved out of our CWA and we do not expect
any more severe storms to develop tonight. We have cancelled the
Tornado Watch for all of the counties in our CWA.
&&
.PREV DISCUSSION... /ISSUED 735 PM CDT Tue Apr 12 2022/
AVIATION... /00Z TAFS/
Dry-line to retreat west this evening and moderate the near record
temps along and west of I-35. Dew points in the low 70s over the
Coastal Prairies should help with drawing surface temps down to where
a low level cig should form, but it will probably not happen until
around midnight. With upper troughing still to the west, we`ll see
the overnight winds stay up and even be gusty to near 20 knots at
times. This should point to the cigs staying in the MVFR levels. No
convection is expected as the CAP is supposed to strengthen, but a
few streamer showers can`t be ruled out. Clouds should get kicked
out by around 15Z when the Pacific front arrives and kicks up the
wind gusts up to around 25 knots again.
PREV DISCUSSION... /ISSUED 423 PM CDT Tue Apr 12 2022/
UPDATE...
Thunderstorms have begun to form along the dryline and will continue
to move toward the northeast. Low level wind shear is quite strong in
the warm airmass to the east. Supercell thunderstorms will be
possible as the dryline moves into this warm air and some storms
could be severe. While large hail is the most likely threat,
tornadoes will also be possible and SPC has issued a Tornado Watch
for Burnet, Blanco, Hays, Travis, and Williamson Counties until 11
PM.
PREV DISCUSSION... /ISSUED 208 PM CDT Tue Apr 12 2022/
SHORT TERM (Tonight through Wednesday Night)...
Bottom line: confidence in storms developing somewhere in the area
is higher than it was this morning. However, coverage is still
expected to be widely scattered so not every location will be
impacted.
The forecast remains on track today with a somewhat diffuse dryline
beginning to push across the Rio Grande just after 18Z, just a bit
behind an H5 shortwave evident in water vapor imagery and RAP
analysis that was over the Rio Grande Plains. Behind the dryline,
we`ll see RH dip into the teens and winds increase to 10-15 mph, and
a Red Flag Warning remains in effect for our western counties
through 9pm. One small storm on radar clipped our far southeastern
counties early this afternoon, but otherwise skies are now clear
west and continue to clear out east.
If the dryline can tighten up the Td gradient a bit and advance
east, it`s ascending branch would easily mix out our capping
inversion in tandem with the mid-level PVA-induced lift moving
through. ACARS soundings and the 18Z DRT RAOB indicate the cap
continues to weaken but is not quite fully eroded. With storms
developing to our north from Menard to Runnels counties, we are
gaining confidence that storm development is imminent somewhere in
our area soon. Not 100% confident just yet, but we anticipate storms
are likely to develop somewhere in the area between the longitudes
of Rocksprings and Austin between 2:30-6pm. If they do they`ll have
3kJ/kg to work with along with increasing deep layer shear near 40
knots. Mainly discrete, supercellular modes are favored initially,
and large to very large hail will be the primary risk should storms
develop, with damaging winds also possible. However, there is also a
low-end threat for tornadoes, particularly over our far northeastern
counties. Should storms develop, they`ll likely be moving across the
highly populated I-35 corridor during the evening rush hour before
exiting our area to the east by 9pm.
The warm, moist airmass will remain in place overnight. Expect the
cold front to move in through the morning hours Wednesday. There is
a very low chance for frontal showers or perhaps a storm in the
morning over our far northeastern areas, but most guidance keeps
this activity out of our area. That said, can`t completely rule out
an isolated severe storm in the morning along the US-77 corridor.
Winds shift to the NW and advect in much drier air behind the front
as well as clear skies. With temperatures not too much cooler,
(highs still in the 80s and 90s), RH will likely dip into the single
digits for many areas Wednesday afternoon. Winds will increase to 15-
22 mph over western and northern portions of the area and 10-18 mph
for the Coastal Plains during the day gusts as high as 25-30 mph may
occur along and west of I-35 for a few hours. Will hold the Fire
Weather Watch as is for now but it will be upgraded to a Red Flag
Warning after today`s expires. Winds drop off quickly during the
evening and we`ll have some more comfortable lows by Thursday
morning in the upper 40s north and 50s elsewhere.
LONG TERM (Thursday through Tuesday)...
A zonal flow aloft is forecast to prevail across the area from
Thursday into Saturday. By Saturday afternoon into the evening, the
flow shifts to the northwest and pushes a series of disturbances
over our area. At the surface, an east to southeast wind is forecast
for Thursday and shifting to the southeast and south during the day
on Friday as a surface high pressure ridge develops across the
region. The GFS solution likes to bring light QPF across the coastal
plains and southeast counties on Friday afternoon while the ECMWF
brings a cluster of storms across the Burnet and Llano Counties. The
NAM is dry while the Canadian shows light QPF across the coastal
plains during the morning period. Due to the uncertainties shown by
the models, we are going for a slight chance for showers and storms
mainly for areas southeast of Interstate 35.
Dry weather conditions continue into the first part of the weekend.
However, there is a lot of uncertainties during the Saturday and
Sunday time frame. And here is why. The GFS pushes the frontal
boundary across the Hill Country on Saturday afternoon with some
light QPF across the Edwards Plateau and western Hill Country. The
ECMWF and Canadian solutions keep the area dry with the boundary
remaining to our north.
By Sunday morning, the GFS pushes back the boundary to the north
while the ECMWF and Canadian models push the frontal boundary to the
south and into the Hill Country. So, this coming weekend could be
dry for some people with some communities getting lucky with much
needed rain.
Rain chances continue on Monday and Tuesday as a stronger frontal
boundary signal is evident in all medium range models.
As far as temperatures go for later in the week into the weekend
expect highs in the 80s and 90s on Thursday through Sunday and near
100 across the southwest on Saturday and Sunday afternoons.
FIRE WEATHER...
Fire weather concerns still in place for Thursday as near critical
to critical weather exist for areas along and west of Highway 183.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 70 92 53 86 61 / 20 20 0 - -
Austin Bergstrom Intl Airport 71 92 51 86 60 / 20 20 0 - -
New Braunfels Muni Airport 71 94 52 88 61 / 20 - 0 - -
Burnet Muni Airport 68 89 50 85 61 / 20 10 0 0 -
Del Rio Intl Airport 67 92 55 92 66 / 0 0 0 0 0
Georgetown Muni Airport 71 92 50 85 59 / 20 20 0 0 -
Hondo Muni Airport 69 95 52 92 61 / 10 0 0 - -
San Marcos Muni Airport 69 94 51 88 60 / 20 20 0 - -
La Grange - Fayette Regional 72 91 56 86 63 / 20 30 0 - -
San Antonio Intl Airport 71 94 55 88 63 / 10 0 0 - -
Stinson Muni Airport 72 98 57 91 65 / - 0 0 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Wednesday morning through Wednesday evening
for Atascosa-Bandera-Bexar-Blanco-Burnet-Comal-Dimmit-Edwards-Frio-
Gillespie-Guadalupe-Hays-Karnes-Kendall-Kerr-Kinney-Llano-Maverick-
Medina-Real-Travis-Uvalde-Val Verde-Williamson-Wilson-Zavala.
Red Flag Warning until 9 PM CDT this evening for Dimmit-Edwards-
Kinney-Maverick-Real-Uvalde-Val Verde-Zavala.
&&
$$
Short-Term/Aviation...Oaks
Long-Term...05
Decision Support...Treadway
Area Forecast Discussion
National Weather Service Grand Rapids MI
904 PM EDT Tue Apr 12 2022
LATEST UPDATE...
Update
.UPDATE...
Issued at 903 PM EDT Tue Apr 12 2022
It would seem to me that showers should be developing over
central Lake Michigan within the hour and those showers should
quickly develop into scattered thunderstorms. I would also think
there is a good chance for small hail (less than 1 inch) from
these storms as mid level lapse rates (700 to 500 mb) are expected
to be in the range of 7 to 8.5c (23z HRRR). There is also decent
low level jet, centered southwest of Chicago for severe hours
before it begins to weaken and drift ESE toward western Ohio
around 5 am. Between midnight and 3 am there is 60 to 65 knot
speed max southwest of Chicago with a 20 to 30 knots of speed
convergence over the west Central CWA during that time. Moisture
transport vectors are pointed northeastward into Southwest
Michigan. There is between 500 and 1000 j/kg of mid level cape in
the midnight to 5 am time frame over most of Southwest Michigan.
On the other hand we have condensation pressure deficits in the
8000 to 1200 ft layer between 50 and 80 mb (to dry for clouds) in
that layer. So my thinking is this will be somewhat like 2 nights
ago. We will see scatted storms develop that move quickly
northeast around 40 mph. Many of these storms will produce small
hail. Gusty winds are possible given the 700 j/kg of dcape but
there is a decent low level inversion so it may be hard to mix
that down to the ground.
The bottom line is I do not expect severe storms but I do expect
some thunderstorms, mostly north of I-96 in the 11 pm to 4 am time
frame. They will be most active north or Route 20 in the 1 am to 3
am time frame.
There will then be a break in the convection after that until the
southern stream shortwave convection arrives after sunrise.
&&
.DISCUSSION...(This evening through next Tuesday)
Issued at 207 PM EDT Tue Apr 12 2022
- Thunderstorms developing tonight
A surface warm front down in the mid MS river valley will lift
northward into lower MI tonight. An 850 mb low level jet arrives
here in MI as the front approaches along with elevated
instability. Showalter indices of -2 to -4 are predicted around
midnight. Scattered thunderstorms are expected to develop and
increase as the front and jet track through the region with
northern zones likely to see the most coverage of thunderstorms.
Mid level lapse rates steepen up and deep layer shear values are
over 40 knots...so there is some potential for hail out of the
thunderstorms. The steepest lapse rates are shown to occur across
our northern zones...around Route 10. We will continue to hold on
to high POPs north of the Muskegon to Lansing area for tonight.
- Slight chance for severe weather Wednesday into Wednesday night
The models show the stronger deep layer shear setting up north and
west of the CWA to start the day. After 22z is when the shear
starts to increase steadily from the west. SPC HREF surface based
CAPE values are shown to remain under 1000 J/kg through the day.
A mid level vort max moves in from the southwest for the late
morning to early afternoon hours...which may support one round of
storms. Given the relatively low CAPE forecast and limited deep
layer shear...any severe weather for middle part of the day would
appear to be isolated. The surface front arrives overnight with
strengthening deep layer shear. The instability is shown to be
diminishing. However stronger dynamics start to move in along the
approaching frontal zone as a potent mid level vort max lifts up
from the southwest. The flow aloft becomes highly diffluent as
well. How much if any severe weather we see will be impacted by
how much instability will be around. Thus timing will be
important. If storms do develop...they could feature some severe
weather given the stronger dynamics and shear that will be in
place. Our convective setup for Wednesday will be impacted by how
the pattern evolves tonight...so changes are possible.
- Heavy rain possible
While the storm motion will be relatively fast...models are
showing the risk for multiple rounds of storms. The last couple of
runs of the HRRR show some swaths of over 2 inches and WPC has the
area under a marginal risk for excessive rain. As a result the
potential for urban and poor drainage flooding exists.
- Possible wind impacts Thursday
Bufkit overviews from the NAM and GFS show deeper mixing
developing on Thursday across the CWA. Mixing heights top out
around 40 to 45 knots which could translate to surface gusts
around those values. These winds would be high enough to cause
some power outages. We will continue to highlight this risk in
social media posts and in messaging.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 748 PM EDT Tue Apr 12 2022
Currently skies are partly cloudy with mid and high clouds across
the GRR TAF sites at 730 pm. However there is a warm front to our
south pushing in our direction. There is a band of MVFR and some
limited IFR (as would be typical) close to the warm front over
IN,IL and eastern OH. There is currently no convection on the warm
front. However there is a active area of showers and a few
thunderstorms across NE WI, that are heading east northeast.
Those storms would pass north of Route 10 in central Lower
Michigan if the continue to track as they are doing now.
As I stated above, for the most part the showers and
thunderstorms over WI and now moving toward northern Lake
Michigan, should spread into northern Lower Michigan by 01z to 03z.
It would not be out of the question for a storms to develop a
touch father south in the 03z to 06z time frame. If that does
happen the northern TAF sites are more likely to see them than are
the southern TAF sites. Small hail is possible from the stronger
storms. Again if they happen, they should be out of the TAF sites
in the 06z time frame.
Meanwhile that area of MVFR/IFR cigs will head this way and reach
our TAF sites in the 03z to 05z time frame. Once they move in they
will remain around through Wednesday evening.
Winds will be very strong above the surface tonight. 50 knots will
get as close as 1000 ft AGL by 06z so I have continued the low
level wind shear in our TAFs tonight.
Another area of showers and few thunderstorms is expected for
late Wed morning into early evening. MVFR/IFR conditions are
expected at that time. The showers Wednesday afternoon should be
widespread and impact all TAF sites. It would not be impossible
for a few of the thunderstorms to become severe toward evening but
the SPC SREF had only a 10 pct chance at that time.
&&
.MARINE...
Issued at 207 PM EDT Tue Apr 12 2022
A strong storm system will move into the marine zones over the
next couple of days. One low level jet tracks in this evening and
that will generate some stronger wind gusts along the lakeshore.
Those gusty winds will continue through Wednesday as a strong cold
front approaches from the west. The front tracks through Wednesday
night and the cold air advection will strengthen on Thursday. This
will result in deeper mixing and possible gales.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...Gale Watch from Thursday morning through Thursday evening for
LMZ844>849.
Small Craft Advisory until 8 AM EDT Thursday for LMZ844>849.
&&
$$
UPDATE...WDM
DISCUSSION...MJS
AVIATION...WDM
MARINE...MJS
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
1049 PM EDT Tue Apr 12 2022
.SYNOPSIS...
Retreating high pressure will shift to the East Coast overnight.
Unsettled weather returns Wednesday with a front bringing
showers and thunderstorms. Above normal temperatures will drop
to near normal readings late in the week behind the front.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Partly to mostly cloudy skies will continue through the night as
lower clouds diminish but higher level clouds increase. South
winds will persist and perhaps strengthen a bit overnight.
Forecast lows look on track.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
A mid-level shortwave advancing northeast in deep southwesterly
flow provides the impetus for showers and thunderstorms
Wednesday... starting in the mid-morning over the Tri-State
region and reaching central Ohio by late afternoon. Guidance
generally agrees there will be a brief respite into the early
evening hours, following by pre-frontal convection. Highs
Wednesday will reach well into the 70s. Winds may gust to
around 30-35 mph during peak heating.
For Wednesday late evening into the overnight, there remains
plenty of uncertainty on timing of a band of pre-front storms.
Earlier timing such as the 12Z HRRR depicts would increase the
chance of damaging wind gusts due to better instability. For
now, have indicated a broad period of PoPs to cover this
instability, and also have kept mention of damaging wind gusts
due to clear indication on all the CAMs of a linear mode along
with shear of 40-50 knots. Also kept mention of isolated tornado
potential in the HWO due to expected QLCS-nature of the
convection.
Frontal passage is likely to occur after midnight behind the
thunderstorm activity. This leads to dropping dewpoints and lows
dipping into 40s by early Thursday morning.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
On Thursday morning, the aforementioned (rather large) low will be
positioned over northeastern Minnesota with its associated cold
front extending from Ontario down through the Appalachian mountains
continuing through the Louisiana coast into the Gulf of Mexico. As
the system continues to propagate off to the east, high pressure
moves into the forecast area bringing dry conditions for the
remainder of Thursday into Friday.
Gusty winds will be the primary post-frontal concern Thursday
morning. While deterministic guidance has been trending wind speeds/
wind gusts lower, still kept gusts between 25-30kts at start of
Thursday as frontal boundary exits the area. As the day continues, a
slightly tighter pressure gradient continues to sit over the
northern half of the CWA so gusts between 20-25kts are expected in
areas north of I-70 while winds in areas south are anticipated to
decrease in intensity during afternoon hours.
The closed low continues to slowly move east/northeast throughout
this time frame and ejects mid-level vorticity around its southern
base which could help force some pcpn Friday night into Saturday
morning. Confidence here is lower, so kept slight pops throughout
the CWA.
After this upper level low moves out toward the Atlantic/ Nova
Scotia area, northerly flow returns to our area and temperatures
trend cooler than normal for the next several days. Saturday highs
reach low 60s in the southern CWA and mid 50s in the north. Sunday
trends even cooler, with highs in the mid to low 50s for the
majority of our area. In fact, there is a signal for frost in parts
of our western counties Sunday morning as low temperatures dip to
mid/low 30s in spots combined with light wind and clearer skies.
Pcpn chances ramp up again near the end of the weekend as a larger
wave of energy begins to work its way into the area from our west.
Unfortunately, model guidance varies quite a bit during this time,
both in terms of location and timing. Therefore, have kept chance
pops in grids until better agreement between models.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
VFR will prevail through the night and well into Wednesday
morning. Winds will increase to 10 to 15 kt overnight and then
strengthen further after 13Z with gusts over 25 kt at times. A
couple of areas of showers are forecast to move northeast across
the region. Fair amount of uncertainty with timing/coverage.
Initially expect conditions to remain VFR but as low levels
moisten, ceilings will fall to MVFR, likely dropping below 2kft
for a period of time late in the period. There could be some
embedded thunder within these showers and there could be a drop
in visibility as well.
OUTLOOK...Thunderstorms are likely Wednesday night, potentially
producing very strong wind gusts. After the thunderstorms move
through, MVFR ceilings are possible late Wednesday night into
Thursday morning.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...CA
AVIATION...
Area Forecast Discussion
National Weather Service Lincoln IL
816 PM CDT Tue Apr 12 2022
.SYNOPSIS...
Issued at 805 PM CDT Tue Apr 12 2022
Windy and warm conditions will prevail across central Illinois
tonight...with a few showers developing toward dawn. Strong to
severe thunderstorms will be likely Wednesday afternoon and
evening, especially for locations east of the Illinois River.
&&
.UPDATE...
Issued at 816 PM CDT Tue Apr 12 2022
A warm front continues to lift northward through central Illinois
early this evening, with winds veering to S/SE and gusting 25 to
35mph. With only weak upper forcing in place, the front has not
generated any showers thus far and is not expected to do so for
the remainder of the evening. Meanwhile further west, a line of
thunderstorms has developed along a dryline across eastern Iowa
into north-central Kansas. These storms will track E/NE as the
night progresses and may spill into the Illinois River Valley in
a greatly weakened state toward dawn. In addition, a short-wave
trough currently over the Lower Mississippi River Valley will
trigger scattered showers/thunder as it lifts northward into the
Ohio River Valley late tonight. Have continued to go with a dry
forecast until after 08z/3am when showers/storms begin to spread
into the SE KILX CWA...then after 10z/5am when scattered showers
arrive in the Illinois River Valley. High chance to likely PoPs
will be focused along/south of a Paris to Shelbyville line by
daybreak...with low chance PoPs elsewhere around the area.
&&
.SHORT TERM...(This evening through Wednesday)
ISSUED AT 259 PM CDT Tue Apr 12 2022
Afternoon water vapor imagery reveals a couple waves that will
bring multiple rounds of showers and thunderstorms to central
Illinois through Thursday evening. This afternoon, a shortwave
trough is noted over central TX and is progged to lift northeast
across southern Illinois by early Wednesday morning. Showers and
perhaps a few storms will be possible with this initial wave over
portions of SE and east central Illinois, though instability will
be weak during that time frame and convection will remain elevated
limiting any severe threat with this initial wave of precip.
Meanwhile, a strong upper wave is over south central Montana this
hour while a deep surface low is analyzed over central Nebraska.
The surface low is progged to move slowly ENE across southern
Minnesota overnight with a trailing cold front pushing across Iowa
and Missouri where a line of strong to severe thunderstorms will
develop. This line of storms is expected to approach the Illinois
River Valley early Wednesday morning in a decaying state given
the time of day. Remnant showers and possibly a few non-severe
storms are expected to move across central Illinois through the
morning. The extent and exact timing of this initial round of
precip from both the cold front and the southern stream wave will
need to be closely monitored as it will delay recovery of
instability through the day Wednesday which comprises the primary
area of uncertainty with respect to the severe threat that will
develop later in the day.
The cold front is expected to push from the Illinois River Valley
towards the I-55 corridor through the early to mid afternoon
hours. With strong moisture transport due to favorable
trajectories off the Gulf of Mexico, dew points are expected to
surge into the 60s Wednesday as very steep lapse rates associated
with an elevated mixed layer overspread central Illinois. Guidance
suggests that 800-500mb lapse rates will exceed 8 C/km at times
Wednesday afternoon which will contribute to MLCAPE values pushing
possibly as high as the 1500-2500 J/kg range if all these
ingredients come together. As mentioned earlier, the amount of
recovery will be the big question mark through the day given the
morning round of precip and cloud cover early in the day. A number
of models are much more conservative on the amount of
destabilization, with CAPE values topping out more in the
500-1000 J/kg range. Despite uncertainty in the amount of
instability, there is high confidence in strong deep layer shear
exceeding 50 kt with much of this focused in the lowest 3-km.
With these ingredients in place, storms are expected to redevelop
along the cold front Wednesday afternoon and quickly grow upscale
as they sweep east across central Illinois through the remainder
of the afternoon and evening. Shear/instability parameter space is
favorable to support organized severe thunderstorms with the
primary hazard being damaging straight line winds. Given the
strong 0-3km shear values of 40-50kt along the front, do also
anticipate mesovortices to form supporting a QLCS tornado threat.
The confidence in severe storms is higher south of I-72 and
especially along and south of the I-70 corridor where SPC
introduced a moderate risk earlier today. Have lower confidence to
the north of I-72 given the aforementioned concerns in recovery.
Some of the latest CAMs including the 18Z HRRR have trended the
strongest convection further south. Placement details should
become more clear Wednesday morning. By early to mid evening, the
leading line of storms is expected to begin pushing into Indiana
with precip and severe chances diminishing in its wake.
.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 259 PM CDT Tue Apr 12 2022
By Thursday morning, the cold front will be pushing across the
Upper Ohio River Valley while the occluded surface low continues
to slowly meander northward across the Great Lakes region. High
pressure building across the lower to mid Mississippi Valley will
contribute to a strong pressure gradient across central Illinois
resulting in breezy west to southwest winds through the day.
Meanwhile, deep mixing will help to tap into stronger flow aloft.
Surface gusts in excess of 30 kt are a decent possibility and will
need to monitor the potential for occasional gusts near 40 kt
which would reach wind advisory criteria. Colder air wrapping
around the low will overspread the area through the day and
temperatures and afternoon highs will be a solid 10 to nearly 20
degrees cooler compared to prefrontal conditions.
Winds remain breezy to start the day Friday, but not quite as
strong as Thursday and should gradually diminish with approaching
col area moving overhead Friday afternoon. Will have to monitor
for low precip chances as WAA aloft helps to saturate the mid
levels. Forcing is somewhat limited Friday with H5 height rises
still showing slightly positive tendencies, but upper level
divergence in the LER of the jet and WAA will support at least a
chance of rain Friday.
An expansive surface high will overspread the region to start the
weekend resulting in fair weather Saturday, albeit still below
normal with northwest flow aloft. A compact wave emanating from
the Pacific NW will dig across the Midwest late Sunday into Monday
bringing the next chance for rain to central Illinois. A
reinforcing shot of cold air behind this system will bring temps
back to near the freezing mark Monday night and Tuesday night.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 639 PM CDT Tue Apr 12 2022
Complex aviation forecast over the next 24 hours...with the
primary concern being timing of convection at the central Illinois
terminals on Wednesday. Line of storms will develop along a
dryline across Nebraska/Kansas this evening...then will spill into
the Illinois River Valley in a much decayed state toward dawn.
Have only included VCSH at the TAF sites during the morning hours
accordingly. The main round of convection will develop/spread
northeastward into the region toward midday...then will push east
of the terminals by early Wednesday evening. Still quite a bit of
uncertainty about timing/duration of thunder, with KPIA perhaps
being missed entirely. Have therefore only mentioned VCTS, with
thunder mention ending along/west of I-55 by late afternoon as the
emphasis shifts further east and south. Winds will be very
strong/gusty...with southerly gusts of 25-35kt tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Barnes
SYNOPSIS...Barnes
SHORT TERM...Deubelbeiss
LONG TERM...Deubelbeiss
AVIATION...Barnes
Area Forecast Discussion
National Weather Service Indianapolis IN
1142 PM EDT Tue Apr 12 2022
...Updated Aviation Discussion...
.Forecast Update...
Issued at 948 PM EDT Tue Apr 12 2022
Radar trends and HRRR suggest convection associated with
upstream waves over the South will not make it in to southwestern
parts of central Indiana until after 4 AM. So, slowed down the PoPs
though 12z Wednesday. Breezy south winds with gusts to 30 mph along
with increasing convective debris canopy will result in near
stationary temperatures in the 60s through the overnight. Although
instability will be weak per instability progs and BUFKIT, there
will still be enough for thunder.
&&
.Short Term...(This evening through Wednesday night)
Issued at 254 PM EDT Tue Apr 12 2022
...SEVERE THUNDERSTORM THREAT WEDNESDAY INTO WEDNESDAY NIGHT...
BOTTOM LINE UP FRONT
*A line of strong to severe thunderstorms will move across Indiana
Wednesday evening
*Damaging winds and a few tornadoes are the primary threats, along
with heavy rain
*Uncertainty remains with timing and extent of severe potential
Through Tonight
A cold front dropped southward across the region last night, and
stalled out just south of our CWA. The stalled front is now lifting
northward as a warm front due to a large trough ejecting out of the
Rocky Mountains. In response, clouds have been increasing from
south to north today. Cloud cover will continue to progress
northward as the day goes on with a few showers possible. While
there is some weak isentropic lift associated with the advancing
front, overall forcing is limited and thus not expecting
widespread shower activity this afternoon.
An upper-level shortwave trough currently over Texas will get
absorbed in the flow ahead of the ejecting trough and lift
northeastward towards Indiana. This feature is not expected to phase
with the trough, however. Instead, it will remain a separate feature
and ride northward just ahead of the main trough. As it moves north
tonight, showers and thunderstorms are likely after 12Z.
Wednesday and Wednesday Night
Convection should be ongoing by Wednesday morning as the lead
shortwave moves through and exits to the northeast. By midday, the
main trough should begin to take on a negative tilt and move into
our area. Divergent flow aloft will promote lift along and ahead of
an advancing cold front. Hi-res models currently depict intense
convection developing along the front, reaching Indiana late in the
afternoon or in the early evening. Current timing appears to be
clustered around 00Z. Mean flow oriented parallel to the front imply
a linear convective mode is preferred. Sufficiently curved
hodographs would imply a few embedded circulations within the line
could develop. So in addition to damaging wind gusts, a few
tornadoes are also possible as these storms move across the area.
Warm air advection ahead of the main line of storms could
destabilize the environment enough that a few discrete cells are
possible ahead of the line. Deep layer shear over 50 kts and
sufficient helicity could lead to any discrete cells posing a hail
and tornado hazard.
One caveat to the severe threat is the morning convection.
Widespread early morning rainfall may stabilize the environment
enough to reduce the extent of the discrete cell severe threat later
in the day. However, if the early rain is on the lesser end of the
range of possibilities, the atmosphere may become more destabilized
and the potential for discrete convection may end up being higher.
Regardless, strong dynamics and forcing will be enough for the
linear severe potential to remain despite variations in potential
environmental stability.
In addition to the severe potential, the aforementioned strong
low- level flow could lead to general wind gusts over 30 to 35 kt
wind gusts across the region tonight into tomorrow. The gusty
winds, along with the severe weather threat, will diminish once
the cold front has passed. Cooler air will filter into the region
with lows as low as the upper 30s by early Thursday morning.
&&
.Long Term...(Thursday through Tuesday)
Issued at 254 PM EDT Tue Apr 12 2022
A milder period can be expected in the long term period, with flow
becoming quasizonal or weakly cyclonic late in the week into the
weekend as the larger closed low pressure system lifts northeast out
of the region and fast upper level flow promotes a more progressive
pattern.
Cooler temperatures, near to slightly below normal, will move in
Thursday in the wake of an exiting cold front and then persist
through the period. An elongated jet aloft will continue gusty winds
into the day Thursday as well, with gusts up to around 40 MPH mainly
for areas to the NW. At the surface, high pressure will be passing
through the area Thursday as well, so expect mostly clear skies with
the gusty winds.
Weak upper level waves may promote low chances for showers Friday
into Friday night, with slightly more substantial shower chances
needed late in the weekend into early next week as a somewhat more
amplified upper level trough moves along the northern periphery of
the country into the Great Lakes.
For early next week, models are suggesting at another upper system
that will bring better chances for rain, but given the variety in
solutions, it is too soon to nail down any details.
&&
.Aviation...(06Z TAF Issuance)
Issued at 1141 PM EDT Tue Apr 12 2022
IMPACTS:
-Mostly VFR flying conditions overnight, but brief MVFR ceilings
developing in convection after 10z or so.
-Thunderstorms possible after 10z. Strongest storms after
21z.
-Winds 160-200 degrees 15 to 20 knots with gusts to 30 knots through
03z Thursday. Then, winds switching to around 270 degrees behind
the cold front.
-Non-convective low level wind shear through 11z.
DISCUSSION:
A strong storm system will lift northeast into the northern Plains
today. Meanwhile, associated cold front will sweep through the
terminals late tonight. The front, combined with strong wind shear,
instability and deep moisture will bring widespread showers and
thunderstorms to the terminals through tonight. The strongest storms
will move through this evening. Mostly VFR flying conditions will
deteriorate to MVFR at times after the showers arrive this morning.
Low level wind shear will be a threat with the low level jet
overhead. Breezy or windy conditions are expected through the TAF
period.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Update...MK
Short Term...Eckhoff
Long Term...KH
Aviation...MK
Area Forecast Discussion
National Weather Service Jacksonville FL
910 PM EDT Tue Apr 12 2022
.UPDATE...
Mostly clear over the area this evening with sfc high pressure
well to our east. Prevailing south to southeast low level flow
shown in the obs and latest VWP and JAX sounding. Sea breeze
induced flow is fairly strong for coastal areas with winds up to
15 mph and gusty but will settle down overnight. Noted JAX sounding
and JAX VWP showed around 20 kt at 1000 ft this evening. Otherwise,
expect to see more high clouds streaming in from the west per
latest satellite trends and HRRR guidance. We continued to keep
the lows a bit above the min temp guidance but still tweaked them
a bit lower based on latest performance of the MOS and NBM
forecasts. Some patchy fog is possible and mainly toward interior
areas of southeast GA early Wednesday morning. Otherwise, no
significant changes in the forecast at this time.
.MARINE...
Winds and seas are on track in the latest CWF with only minor
adjustments needed in forecast grids. Main change was with the
winds initially tonight near 15 kt but consensus shows winds will
settle more southerly at 10-15 kt toward sunrise.
&&
.PREV DISCUSSION [748 PM EDT]...
.NEAR TERM [Through Tonight]...
High pressure will remain in command of the sensible weather
tonight. Aside from flat cumulus developing along the Atlantic
sea breeze and across inland SE GA and the Suwannee Valley, mostly
clear skies will prevail this afternoon. Breezy conditions will
continue along the coast through the rest of the afternoon with
gusts up to 25 mph before diminishing this evening. Dirty upper
ridge will introduce bouts of cirrus into the area this evening.
There should be enough boundary-layer wind and high clouds in
place to prevent widespread, organized fog tonight but patchy fog
development will be possible in wind-sheltered areas. Lows
tonight will be warmer tonight especially at the coast where lows
will be in the mid/upper 60s while inland areas will read in the
low 60s.
.SHORT TERM [Wednesday Through Thursday Night]...
Warm, moist southerly flow continues Wednesday with surface high
pressure well east in the open Atlantic. Meanwhile aloft, strengthening
southwesterly flow will develop ahead of an upstream impulse. An
influx of high clouds will precede the upper impulse Wednesday and
continue to drift overhead Thursday ahead of an advancing cold
front from the northwest. The cold front will slow and weaken as
it pushes into SE GA Thursday afternoon. Despite weakening,
sufficient convergence along the boundary will support scattered
showers and isolated storms across SE GA during the afternoon
hours. Further south in NE FL shower chances will be lower due to
stubborn low stratus and drier, warmer air in the low-levels.
Strong warm advection will boost temperatures well into the 80s by
Thursday with muggy overnight lows in the mid/upper 60s both
nights.
.LONG TERM [Friday Through Tuesday]...
A weakening cold front will slow, become diffuse, and eventually
stall somewhere across SE GA. Low level moistening will push PWAT
toward 1.5" with model soundings indicating afternoon instability
in the range of 1200-2000 J/Kg CAPE. Synoptic shear production
looks meager at this time but mesoscale/sea breeze influence may
lead to locally elongated hodographs and focused convergence
during Friday afternoon. Expect stronger storms to favor these
enhanced areas of convergence, with scattered run-of-the-mill
thunderstorms elsewhere; strong storms will be capable of gusty
winds and hail. Frontal zone will lift slightly northward Saturday
before another decaying, upstream cold front overtakes and presses
into the area Sunday and stalls once again. These features will
continue unsettled weather through the weekend and into early next
week. Late in the period, ensemble systems generally agree on a
sweeping frontal passage will occur Tuesday with cool, northwest
flow in its wake. Above normal temperatures are expected through
the weekend and into next ahead of the stronger cold front.
.AVIATION...
[Through 00Z Thursday]
Prevailing VFR expected through the forecast period with mainly SCT-
BKN cirrus and some FEW-SCT cumulus at times. Some low chance for
patchy fog late tonight mainly inland TAFs between 06Z-12Z Wednesday,
but at this time no significant restrictions are indicated in the
forecast based on latest model guidance and soundings. Sfc winds
from the southeast continue a bit breezy this evening roughly 8-14
kt and gusty. These winds will settle lower toward and after
midnight. Southerly winds initially Wednesday morning will trend
toward the southeast during the aftn again around 8-14 kt with
some gusts near 20 kt.
.MARINE...
High pressure will remain well to the east through the end of the
week. Meanwhile, a cold front will approach from the northwest on
Thursday and stall across the waters on Friday before wobbling
slightly north of the waters this weekend. The frontal zone will
support scattered showers and thunderstorms. Southerly flow will
increase to SCEC levels by Wednesday night through Thursday as
gradients tighten ahead of the front then relax Friday and through
the weekend in the vicinity of the stalled boundary.
Rip Currents: Influence of sea breeze and shore-parallel currents
will lead to Low to Moderate Rip Current risk at area beaches
through Thursday.
.FIRE WEATHER...
Increasing moisture and persistent southerly surface and
transport winds expected through Thursday. On Wednesday,
increasing southerly transport will lead to locally high daytime
dispersion across the Okefenokee NWR, Ocala NF, and other inland
forests along I-75. A weak cold front will enter and stall over
the area Friday with scattered showers and thunderstorms along it.
Unsettled weather will continue through the weekend and into
early next week with the passage of couple more frontal systems.
Patchy fog is expected tonight along and east of I-95.
.HYDROLOGY...
The Altamaha River continues to rise with portions entering minor
flood stage this evening. Santa Fe River continues to recede
however portions of the river will remain in flood. Unsettled
weather will bring more precipitation to the area this Thursday
and through the weekend. Upcoming precipitation is not expected to
exacerbate ongoing flooding or result in new river flooding.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 60 84 63 83 63 / 0 0 20 50 30
SSI 65 79 67 81 66 / 0 0 10 20 30
JAX 60 84 67 86 66 / 0 0 10 30 20
SGJ 65 82 68 84 68 / 0 0 10 30 20
GNV 59 84 65 86 65 / 0 0 10 20 10
OCF 59 85 65 86 66 / 0 0 10 30 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
Area Forecast Discussion
National Weather Service Lake Charles LA
955 PM CDT Tue Apr 12 2022
.DISCUSSION...
Local 88Ds are a little quieter than earlier in the evening with
the afternoon convection driven by the initial disturbance aloft
now mostly east of the forecast area. Spotty convection continues
to pop up in this activity`s wake over the forecast area as
mesoanalysis shows we remain very moist and fairly unstable. Main
feature for tonight looks to be the well organized MCS beginning
to move into nwrn LA from nern TX...the tail end of this feature
looks to miss our nwrn zones on its current trajectory. However
additional convective development is ongoing off its srn flank and
considering our local airmass continues to show good instability
and lapse rates with excellent helicity, will have to keep an eye
on this activity should it get into our area closer to midnight.
POPs/wx grids were updated per latest trends. Elsewhere,
inherited grids/zones look in good shape as is.
Update out shortly.
25
&&
.PREV DISCUSSION... /issued 640 PM CDT Tue Apr 12 2022/
DISCUSSION...
For the 04/13/2022 0000 UTC TAF package.
AVIATION...
Sctd storms on radar late this aftn will continue to move
northeast through the evening, with chcs tapering off overnight.
The passage of the convection has left some breaks in the low
clouds, resulting in what is expected to be a brief period of VFR
conditions early this evening. Given copious low level moisture,
expect MVFR cigs filling back in acrs the area by 03-06Z. MVFR
cigs are expected to persist through day at BPT/LCH/AEX with a
possible improvement to VFR at the Acadiana terminals during the
morning. Another round of SHRA/TSRA will move in from the west
during the aftn ahead of a cool front. S-SE winds will remain
elevated and gusty through the period. Gusts to near 30 KT can
again be expected during the day Wednesday.
24
PREV DISCUSSION... /issued 435 PM CDT Tue Apr 12 2022/
SHORT TERM [Today through Wednesday]...
Showers and thunderstorms are currently progressing across the
area with gusty winds present. Showers and thunderstorms will be
possible into the overnight hours. Some storms could be severe.
A frontal system will be expected to move through the area
tomorrow. Showers and thunderstorms will be expected tomorrow
from the morning into the afternoon and overnight hours. The HRRR
is indicating sufficient CAPE and shear for the possibility of
severe thunderstorms. Damaging wind gusts, large hail, lighting,
and a few tornadoes will be possible. PWATs are showing in the
1.7 to 1.8 inch range which indicates the possibility of flooding.
HRRR soundings also show significant moisture from the low-levels
to the upper-levels.
A significant cooldown will not be expected post-frontal with
drier weather expected on Thursday.
55
LONG TERM [Friday through Monday]...
After an initially cool start Friday morning, an elongated surface
ridge will push towards the east coast during the day turning winds
back out of the south and lifting a warm front out of the gulf.
Dewpoints behind the boundary will climb into the mid to upper 60s
with the warm front providing a weak focus for scattered showers and
thunderstorms. Steady southerly flow will prevail in the wake of the
warm front through the weekend which will will maintain afternoon
highs near or slightly above normal. A surface low will develop over
northern Texas Friday and drift slowly southeast through the weekend
providing a weak focus for isolated to scattered daily afternoon
showers and thunderstorms. Weak perturbations in the otherwise zonal
flow aloft may periodically aid in this development.
A shortwave moving into the Pacific northwest Saturday will swing
rather quickly across the western and central U.S. pushing another
robust cold front through the region Monday dropping temperatures
below seasonal norms through the first half of next week.
Jones
MARINE...
Elevated onshore flow will continue into tomorrow. Showers and
thunderstorms will be possible for the remainder of today through
Wednesday night. Some of the storms could be severe. A Small Craft
Advisory is currently present through tomorrow.
55
LCH WATCHES/WARNINGS/ADVISORIES...
LA...None.
TX...None.
GM...Small Craft Advisory until 7 PM CDT Wednesday for GMZ430-432-435-
450-452-455-470-472-475.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 68 81 53 77 / 80 90 50 10
LCH 68 79 58 80 / 70 90 50 10
LFT 69 81 60 81 / 70 90 80 10
BPT 69 81 59 80 / 40 70 20 0
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...None.
TX...None.
GM...Small Craft Advisory until 7 PM CDT Wednesday for GMZ430-432-435-
450-452-455-470-472-475.
&&
$$
Area Forecast Discussion
National Weather Service Louisville KY
900 PM EDT Tue Apr 12 2022
.Forecast Update...
Issued at 858 PM EDT Tue Apr 12 2022
Things have been relatively quiet so far this evening across central
Kentucky and southern Indiana, with more clouds across the Kentucky
Bluegrass and more sun across south central Kentucky. Where there
has been more sun this afternoon, a few instability-driven showers
and thunderstorms have developed over the past few hours,
particularly along the KY/TN border where MLCAPE values of 1000-1500
J/kg are present. Expect these showers to diminish in intensity and
coverage over the coming hours as the atmosphere stabilizes after
sunset.
Otherwise no major changes to the forecast at this time. Expect
cloud cover to gradually build from south to north across the region
tonight as another surge of low-to-mid level moisture overspreads
the area. After a late evening lull, PoPs will begin to increase
again from southwest to northeast after 13/07Z. A peculiar
manifestation in the high-res guidance is a suggestion by the 12/23Z
HRRR that a remnant MCV left over from ongoing convection across
Texas could make its way into central Kentucky by late tomorrow
morning, potentially impacting the morning wave of precipitation.
For now, this is nothing more than a mere peculiarity until it is
consistently depicted in models/observed.
&&
.Short Term...(This evening through Wednesday)
Issued at 300 PM EDT Tue Apr 12 2022
...Strong to Severe Storms Possible Wednesday Evening and
Overnight...
****************************************************
*** Main Headlines for Wednesday/Wednesday Night ***
****************************************************
- Rain and embedded non-severe storms through early Wednesday
afternoon.
- Gusty southerly winds during daytime (30-40 mph)
- Multiple rounds of severe weather possible Wednesday evening
through the overnight hours
- Severity/timing of storms continues to remain uncertain
A warm front is slowly lifting northward through the region this
afternoon per latest observational guidance. Clouds and showers
lingered for much of the morning hours near the vicinity of the
front, but with it lifting out of the region, we are now starting to
see breaks in the clouds and precipitation. This drying trend should
continue into the evening and overnight hours. The next round of
rainfall looks to arrive early tomorrow morning as a shortwave
embedded within the main trough axis swings into our region. Best
chances for precipitation look to be west of the I-65 corridor. This
round of precipitation should be non severe as instability looks to
be meager with poor low/mid level lapse rates and marginal low level
dewpoints. This rainfall should be pushing north of the I-64
corridor by ~20z. Winds will also be breezy out of the south in the
wake of this rain, with gusts in the 30-40 mph range.
After 20z, attention then turns to the west where a line of strong
to severe storms along a cold front will be ongoing and quickly
racing toward our region. Several high-res CAMs also show a weak
vort lobe ahead of the front and develop a second line of convection
within the warm sector. We could see storms arriving in our western
CWA as early as 21z, but the main front/line will not likely arrive
until after 00z. Confidence with respect to the severity of storms
remains low, as the timing between multiple lines/waves of showers
and storms will impact the overall thermodynamic environment (i.e.,
will we be able to destabilize enough in between rounds of
showers/storms to get strong to severe convection?). Generally
thinking that storms west of the I-65 corridor have the best chance
for severe potential, where the greatest instability corridor will
reside. East of I-65, instability becomes quite meager, and models
tend to weaken convection in this area due to limited or near-zero
instability. Should severe storms form, the main threats would be
damaging straight line wind gusts and isolated embedded tornadoes
within the line. A localized flash flood threat will also be
possible where training of storms occurs. The severe threat should
end in our east by about ~09z.
.Long Term...(Wednesday night through Tuesday)
Issued at 255 PM EDT Tue Apr 12 2022
Long term period features much cooler and drier conditions for our
region. By Thursday morning, the well-advertised cold front will be
departing off to our east, taking with it the precip chances and
above normal temps. Quick moving sfc high will be arriving, helping
to clear out skycover. While Thursday should feature cool post-
frontal NW flow and a drier airmass, heavy rain from the recent
passing cold front may result in some minor river flooding issues.
OHRFC currently forecasts minor flooding at some stage points along
the Green River by later this week, and possibly at Rough Rover too.
Otherwise, not expecting much river flooding issues further east.
Expect temps to be a touch cooler than normal, mainly in the low to
mid 60s.
Warmest day of the long term comes Friday, with temps in the upper
60s and near 70F as the upper level pattern flattens some and the
aforementioned sfc high over the Carolinas filters some warm return
flow into the Ohio Valley. A weak low-level disturbance will bring a
moisture-starved frontal boundary through the region Friday night,
though some isolated to scattered light showers will be possible.
Perhaps enough dry air below 700mb could be enough to evaporate most
precip before hitting the ground, so decided to slightly lower PoPs
for Friday night to keep our chances in the Slight Chance category.
This front will sag south of the region and stall across the Deep
South by Saturday.
A stronger sfc high from Canada will begin to build into the region
on Saturday, resulting in cooler NNW flow. The region may be split
on Sat between drier conditions to our north from the sfc high, and
slight PoPs to our south caused by the stalled boundary just to our
south. Not expecting much in the way of impacts through the weekend.
Temps will slightly get cooler each day through the weekend and into
early next week. CPC highlights the 6-10 day outlook with likely
probabilities of below normal temps. Greatest rain chances of the
period come at the start of early next week as we get another
disturbance moving through the area, but it`s too soon to get into
the finer details at this time.
&&
.Aviation...(00Z TAF Issuance)
Issued at 751 PM EDT Tue Apr 12 2022
The airports will be well within the warm sector of a powerful
spring storm system over the Plains tonight. An area of showers,
with a few embedded rumbles of thunder, over the lower Mississippi
Valley this evening will cruise northeastward into the region
tonight into Wednesday morning, though flying conditions should
prevail VFR outside of locally heavier downpours. Of possibly
greater concern will be brisk surface winds around 10-15kt and
marginal speed LLWS as a low level jet intensifies from the western
Gulf to the Great Lakes.
Tomorrow a sharp cold front will approach from the west with gusty
south winds out ahead of it. Morning showers will become more widely
scattered in the afternoon. We could see some convective
redevelopment by late afternoon, but the main show will be a
potential band of very strong storms moving in from the west
Wednesday evening. Will put some TSRA in the extended planning part
of the SDF TAF, with future TAF issuances employing greater detail
and probably some timing adjustments.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&
$$
Update...CSG
Short Term...DM
Long Term...CJP
Aviation...13
Area Forecast Discussion
National Weather Service Mobile AL
1052 PM CDT Tue Apr 12 2022
.NEAR TERM /Now Through Thursday/...Southwest flow aloft this
evening transitions to westerly difluent flow aloft by Wednesday
evening into Thursday. This is owing to a powerful upper level
trough over the central Plains quickly taking on a negative tilt
during the day Wednesday into the ArkLaTex region and a
subtropical jet nosing into the northern Gulf of Mexico. As this
occurs, a low pressure system occludes across the north-central
midwestern states as a trailing surface cold front races east
across the gulf coast states Wednesday night into Thursday
morning. This feature should transit most of the CWA by Thursday
morning, gradually becoming more diffuse and slowing as it does
so.
For the rest of tonight, we continue to have light to moderate
showers attempting to move into our southeastern MS counties. So
far they have struggled to make much progress and for the most
part a majority of the CWA should remain dry tonight outside of
our interior MS and southwest AL counties. A feature of interest
that recent HRRR runs has been honing in on is an ongoing mature
MCS across western/northwestern Louisiana possibly knocking on our
southeastern MS counties and interior southwestern AL counties by
daybreak. Shear and instability should be sufficient through the
night to support a continuation of this feature with around 500 to
1,000j/kg of CAPE and 30 to 35kts of effective shear across the
area through the overnight hours. It`s a bit early to know exactly
how this will evolve as most 00z CAMs (even the 00z HRRR) were
not as keen on this. With that said, the 00z CAMs have not had a
good handle on the ongoing convection while recent HRRR runs
depicts this better. Given that, I felt it worth mentioning for
now. Future CAMs runs will need to be monitored to gain a
meaningful understanding of how this MCS will evolve before making
any forecast changes at this time. Otherwise, expect isolated to
scattered showers over southeastern MS and interior southwestern
AL through the overnight hours.
If that wasn`t enough to talk about, there is some evidence of a
wake low beginning to develop across south-central Louisiana as
precipitation continues to evaporate across the area. Surface
observations over that area support this development with several
ASOS stations reporting winds gusting from the east/east-
southeast at 30 to 50mph. Latest CAMs even note this feature
transiting east into southeastern MS and southwestern AL within
the next 3 to 6 hours. Confidence on how this evolves and if it
truly makes it into the CWA is low, and thus will hold off on any
forecast changes at this time. If confidence becomes high enough
this will pass over our area then changes to the current wind
forecast would be needed and the possibility of a short fused wind
advisory for portions of the area. Lows should dip into the lower
to middle 60`s.
Wednesday should start off mostly dry barring the aforementioned
MCS doesn`t throw a wrench into the forecast. Ample moisture
return continues with strong daytime heating bringing
temperatures into the lower 80`s for most locations by the
afternoon hours. With forcing remaining well to the west of the
area through Wednesday afternoon, not anticipating much if any
shower or thunderstorm activity for most of the day. It`s once we
get to the evening and overnight hours Wednesday night into
Thursday morning that the weather becomes more interesting.
As the aforementioned upper level difluence overspreads the
region, scattered showers and thunderstorms should develop over
the area from west to east, beginning in the early evening hours.
Models hint at two possible rounds of storms, with the first
belonging to initial convection firing over southeastern MS into
southwestern AL Wednesday evening over the open warm sector. This
convection will develop in around 1,000 to 1,500 j/kg SBCAPE and
30kts of shear. Expect this to mainly be multicellular and pose a
threat for large hail and damaging wind gusts. Can`t rule out a
tornado or two if favorable storm mergers can result in a
mesoscale accident. Confidence in this first round remains low to
moderate. The more confident round will be associated with the
front itself. CAPE values remain near 1,000j/kg during the
overnight hours and shear increases modestly to near 35 to 40kts.
Overall anticipating a squall line to transit the area from
northwest to southeast during the overnight hours into Thursday
morning, with a primary threat of damaging wind gusts. Once again
can`t rule out a tornado or two with the line itself. In addition
to the severe weather threat, localized flash flooding of low
lying areas is possible. This is particularly the case if the line
slows to a crawl and becomes oriented west to east allowing for
training of thunderstorms over the same areas by Thursday morning
into early afternoon. Confidence in this remains relatively low to
moderate. A High Risk of Rip Currents remains in effect through
late Friday night. MM/25
&&
.MOB WATCHES/WARNINGS/ADVISORIES...
AL...High Rip Current Risk through late Friday night for ALZ265-266.
FL...High Rip Current Risk through late Friday night for FLZ202-204-
206.
MS...None.
GM...Small Craft Advisory until 4 PM CDT Wednesday for GMZ630>632-650-
655-670-675.
&&
$$
This product is also available on the web at:
www.weather.gov/mob
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
546 PM CDT Tue Apr 12 2022
.UPDATED for 06Z aviation discussion...
Issued at 536 PM CDT Tue Apr 12 2022
&&
.DISCUSSION...(This evening through Tuesday)
Issued at 230 PM CDT Tue Apr 12 2022
* KEY MESSAGES: (optional)
- Severe thunderstorms are possible through this evening from
southwest and south central Minnesota through east central
Minnesota and into west central Wisconsin. Although isolated severe
weather is possible prior to 7 PM, most of the potential for severe
storms will be from 7 PM onward.
- Strong winds are expected Thursday into Thursday night, with gusts
of 40 to 50 mph possible, especially along and south of the
Minnesota River valley.
Visible satellite imagery this afternoon shows clouds locked in
across the area, with the nearest clearing from southeast South
Dakota into western Iowa. Surface low of around 985 mb was analyzed
over eastern Nebraska. This low will lift northeast through this
evening, and should bring the warm frontal boundary into far southern
and southeast Minnesota after 00Z. Instability will be somewhat
limited, and will be primarily elevated, although the south/southeast
portion of the area could see some storms rooted in the boundary
layer which would enhance tornado potential there. In addition, the
eventual evolution into more of a QLCS structure east of I-35 after
02Z could favor the development of low-level mesovortices and short-
tracked tornadoes and/or enhanced areas of wind damage. Otherwise,
hail looks to be the primary concern over most of the area, including
the Twin Cities metro, where forecast soundings from the RAP and HRRR
favor things remaining elevated. Even with somewhat limited
instability, low-level and deep layer/effective shear will remain
high through the evening, favoring rotating updrafts in discrete
elevated storms, further enhancing the large hail potential. The
forecast 0-3 km bulk shear fields across the southern portion of the
area this evening favor greater than 30 kt of shear with any
potential storm/line motion, which is why mesovortices (as mentioned
above) would be favored if/when a QLCS structure evolves. Meaningful
convection should push east of the area by around 05-06Z, with some
lingering showers possible, mainly over the north.
The surface low will occlude from Minnesota into Wisconsin on
Wednesday, with the bulk of the lingering precipitation staying
north/east of the forecast area, although some PoPs are still
warranted (particularly north of I-94). Cold advection increases
Wednesday night into Thursday, along with the pressure gradient.
Winds look to significantly increase Thursday into Thursday night,
with gusts to 50 mph a possibility (especially from west central into
south central Minnesota). Included gusts above 40 mph for much of the
area Thursday afternoon/evening, and subsequent forecasts should be
able to refine things, with the definite possibility of a wind
advisory being needed at some point.
Medium range guidance is in good agreement after Thursday, with
unseasonably cool temperatures continuing through the weekend,
although precipitation chances are limited and light through that
time. Return flow will precede the next system of note Sunday
afternoon/evening, with sufficient moisture and lift for rain/snow
across the area. It looks to cool off a bit behind this system, with
any significant warming holding off until after the current seven day
forecast period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 536 PM CDT Tue Apr 12 2022
Areas of MVFR/IFR developing this evening as thunderstorms lift up
from Iowa and move across Minnesota and Wisconsin. These storms could
be severe with strong winds and large hail. Expect a strong wind
shift as well with a surface low moving through. Winds will start out
easterly this evening, and then take on a more westerly direction
with strong gusts near 30kts on Wednesday after the surface low
passes through.
KMSP...
No significant changes from the previous forecast. Thunderstorms are
expected later this evening with MVFR/IFR clouds developing as well.
These storms could produce strong winds or large hail. Winds will be
easterly, and then switch northeast and to the north tonight,
eventually becoming westerly on Wednesday. Clouds should lift towards
VFR by the late afternoon and evening.
/OUTLOOK FOR KMSP/
Thu...IFR/MVFR chc -RASN. Wind W 20-25 kts, gusts 40-45 kts.
Fri...VFR. Wind W 20-25 kts, gusts 35-40 kts.
Sat...VFR. Wind WNW 10-15 kts, gusts 25kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
DISCUSSION...WFO MPX
AVIATION...JRB
Area Forecast Discussion
National Weather Service Norman OK
1101 PM CDT Tue Apr 12 2022
...New AVIATION...
.SHORT TERM...
(This evening through Wednesday)
Issued at 331 PM CDT Tue Apr 12 2022
* Storms? - Severe This Afternoon/Evening
* Fire Weather
* Strong Winds
Discussion:
No significant changes to expectations in the big picture with
wildfire potential west and a conditional potential of severe storms
east. The shortwave over north Texas will likely be the main
synoptic-scale forcing mechanism and with that, the highest
potential for storm development late this afternoon and this evening
will be in the southeast. So the big question remains, will there be
storm development on the dryline? Some of the models suggest the cap
weakening and very little negative area on the soundings, especially
across southwest and south central Oklahoma this afternoon. But
without significant forcing near the dryline, that is no guarantee
of storm development on the dryline. And we may be fighting some
subsidence north of the north Texas shortwave. Some of the
convective-allowing models (including the HRRR and the 12Z HiRes-ARW
and 3 km NAM) are showing some potential of development in the SW or
south central. Farther north, there is still more uncertainty on
potential development along the dryline. But if any storms do
develop, the atmosphere is quite unstable with sufficient shear for
supercells. Regardless, without significant forcing on the dryline,
we do not expect widespread storms. We will continue to monitor
mesoanalysis and satellite trends through the day to assess the
potential for development.
In the west, the winds continue to increase across the western and
central Oklahoma and Texas panhandles, and we expect to see winds
increase in northwest Oklahoma this afternoon. The dryline was slow
to mix eastward today, but is in parts of western Oklahoma and
western north Texas where relative humidity is 20 percent or lower.
Expect fire weather conditions to worsen through the afternoon in
the west as the dryline mixes east and very dry air spreads into the
area along with the increasing winds. This remains a potentially
dangerous wildfire situation in the west, especially in northwest
Oklahoma.
Models show a cold front moving across the area tonight into
Wednesday with winds shifting to the NW/N. This could cause problems
to any ongoing fires. Models also show some showers/storms
developing near the front late tonight into Wednesday morning
affecting eastern portions of the fa, mainly along and east of I-35.
Despite cooler temperatures (highs 60s and 70s) Wednesday, gusty
winds, low RH, and dry fuels will lead to near critical/critical
fire weather conditions across western portions of the area. Will
continue with the current Fire Wx Watch.
&&
.LONG TERM...
(Wednesday night through next Monday)
Issued at 331 PM CDT Tue Apr 12 2022
Focus was on the next couple of days. Colder temperatures are
expected Wednesday night/Thursday morning. Freezing temperatures
could be possible in parts of northern OK. Shower and thunderstorm
chances will return to portions of the area Friday into the weekend,
generally along and east of I-35.
&&
.AVIATION...
(06Z TAFS)
Issued at 1056 PM CDT Tue Apr 12 2022
LLWS and temporary MVFR cigs will be the main forecast concerns
overnight. A line of thunderstorms has developed along the cold
front across far northern OK late tonight and this will be watched
for any amendments later for TSRA near PNC. Otherwise, some light
rainfall and brief low cigs may accompany the front into the early
morning hours Wed. A gusty wind shift from the north will also
occur.
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 84 52 67 39 / 20 20 10 0
Hobart OK 92 50 70 36 / 0 0 0 0
Wichita Falls TX 90 58 76 40 / 10 10 0 0
Gage OK 92 41 61 32 / 0 10 10 0
Ponca City OK 85 48 60 33 / 10 30 10 0
Durant OK 81 63 79 42 / 30 30 20 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Fire Weather Watch from Wednesday afternoon through Wednesday
evening for OKZ004>006-009>011-014>017-021>023-033>038-044.
TX...Fire Weather Watch from Wednesday afternoon through Wednesday
evening for TXZ083>090.
&&
$$
SHORT TERM...26
LONG TERM....25
AVIATION...03
Area Forecast Discussion
National Weather Service Pueblo CO
958 PM MDT Tue Apr 12 2022
.UPDATE...
Issued at 957 PM MDT Tue Apr 12 2022
Based on 00z model runs, have cancelled Winter Storm Warnings and
Advisories for the southwest mountains for the remainder of
tonight as any additional accumulations will be spotty and light.
Have maintained Warnings and Advisories for the central mountains
where northwesterly flow will provide favorable orographics for at
least some moderate snow and blowing snow into Wednesday morning
across the higher peaks and passes. -KT
UPDATE Issued at 815 PM MDT Tue Apr 12 2022
High winds have come down and humidity values have crept up above
critical thresholds both ahead and behind a cold front advancing
through the southeast plains. Winds will remain gusty across the
region through midnight but with damaging gusts and critical fire
weather conditions no longer expected, have allowed the High Wind
Warning and Red Flag Warning expire. -KT
&&
.SHORT TERM...(Tonight)
Issued at 344 PM MDT Tue Apr 12 2022
Key Messages:
1) High winds with blowing dust continue this afternoon, mainly
along and south of Highway 50. The High Wind Warning for Teller, El
Paso, and lower Chaffee counties has been cancelled.
2) Fire weather concerns also continue this afternoon, with high
winds and low RH values still supporting high fire danger across
much of southern Colorado.
3) Light to moderate snow continues across the Continental Divide
this evening/tonight.
The downward trend with the winds/gusts noted over the last couple
of hours will continue for the remainder of the afternoon. Latest
RAP analysis still indicating some stronger flow aloft translating
overhead though, which is still supporting some wind gusts to around
60 mph mainly along and south of Highway 50. So, have continued the
High Wind Warning for these areas but did cancel it for Teller, El
Paso, and lower Chaffee counties where these higher gusts are no
longer expected. Have not received any reports of blowing dust here
recently, however, can see some patches of blowing dust on latest
satellite imagery. Additionally, the winds and gusts expected for the
remainder of the afternoon will continue to support blowing dust,
and so have continued the Blowing Dust Advisory this afternoon. As
noted earlier, the precip development and cloud cover along with
some cooler temps have kept RH values higher in spots mainly along
and west of I-25. Elsewhere, RH values are still down to around 10
percent. Despite the higher RH values in spots, did keep the Red
Flag Warning in effect for much of southern Colorado this afternoon,
as the very strong to damaging winds in place are very concerning.
Lastly, snow development has diminished for much of the day across
the Continental Divide, though still snowing across the southwest
mountains. With the snow still occurring across the southwest
mountains and snow anticipated to return to the central mountains
this evening, have kept the winter headlines in place.
.LONG TERM...(Wednesday through Tuesday)
Issued at 344 PM MDT Tue Apr 12 2022
Key messages:
1) Breezy to Windy Conditions with Critical Fire Weather conditions
expected across portions of south central and southeast Colorado
again Wednesday and Thursday.
Latest models continue to indicate moderate to strong northwest flow
aloft across the region on Wednesday, as a secondary trough
translates across the central Rockies tomorrow morning and into the
central High Plains into the afternoon. Increasing northwest
orographic flow will bring another round of snow across the central
mts, with another 1 to 3 inches possible across the higher terrain,
greatest north of Cotton Wood Pass through the day tomorrow. While
can`t totally rule out a few showers spreading out across the
eastern mountains and plains early tomorrow morning, latest models
remain consistent with very dry air mixing into south central and
southeast Colorado behind this passing trough later Wednesday
morning and into the afternoon with dew pts tanking into the single
digits above and below zero areawide by tomorrow afternoon. Although
temperatures cool behind the passing system, with highs only in the
40s to lower 50s expected across the lower elevations, and mainly in
the 20s and 30s over the higher terrain, min rhs are still expected
to drop into the 10 to 15 percent range across the San Luis Valley
and most of the southeast plains. This combined with breezy westerly
winds of 20 to 40 mph developing from west to east through the late
morning and afternoon will once again lead to critical fire weather
conditions being met across the region, and have upgraded the
previous fire weather watch from noon to 7 pm Wednesday for the
southeast plains to a Red Flag Warning, and also added the San Luis
Valley as well as northern El Paso County to the warning.
Breezy to windy westerly flow remains progged across the region
Thursday before slowly diminishing through the day on Friday, as
short wave ridging builds across the Rockies. This will bring
warmer and drier conditions to the region with temperatures
warming back to at and above seasonal levels into the end of the
work week. However, breezy conditions, especially through the
afternoon and early evenings, will lead to continued critical to
near critical fire weather conditions, with Fire Weather Watches
and Red Flag Warnings likely needed across portions of south
central and southeast Colorado through the end of work week.
Model solutions begin to diverge later Saturday and into early
next week, with a new upper-level disturbance possibly passing to
our north which could serve to knock temperatures back down and
bring in some more unsettled weather.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 344 PM MDT Tue Apr 12 2022
VFR conditions are expected for all three sites, KCOS, KPUB, and
KALS for the remainder of the TAF period. Westerly and northwesterly
winds are beginning to diminish, and will weaken to below 35KT by
02Z tonight. Lighter northwesterly winds will remain in place
through the overnight hours, with midlevel clouds moving in by
tomorrow morning. Westerly winds are expected to pick back up
towards the end of the TAF period, around 16-18Z on Wednesday
morning, but are not expected to be as strong as today.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon to 7 PM MDT Wednesday for COZ224-
226>237.
Winter Weather Advisory until noon MDT Wednesday for COZ058-059-
061.
Winter Storm Warning until noon MDT Wednesday for COZ060.
&&
$$
UPDATE...KT
SHORT TERM...RODRIGUEZ
LONG TERM...MW
AVIATION...EHR/RODRIGUEZ
Area Forecast Discussion
National Weather Service Blacksburg VA
815 PM EDT Tue Apr 12 2022
.SYNOPSIS...
A stalled front will retreat northward tonight. Warm and muggy
conditions are expected Wednesday before a strong cold front
approaches the region Thursday. Dry weather with high pressure
Friday and Saturday before another disturbance early next week.
&&
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
As of 545 PM EDT Tuesday...
Forecast remains on track for tonight, no significant changes
made for the evening update. Showers in the NC mountains and foothills
are slowly dissipating, and mid and high level clouds continue
to move across the area.
Previous discussion as follows...
As of 235 PM EDT Tuesday...
Mid to high level clouds remain along with warm temperatures this
afternoon. An isolated shower chance remains over the mountains...
Overall most of the light shower and sprinkle activity has come to
an end across our region with the exception of the North Carolina
mountains/foothills. Hi-res guidance from the HRRR, ARW, and NAMnest
try to hold onto a few lingering showers in these locations as well
as a couple hit or miss showers over the western mountains this
afternoon with our shortwave disturbance working east out Tennessee.
Coverage will be relatively sparse with our stalled front draped
over northern Virginia and back into the southern Ohio River Valley.
This stalled boundary will retreat further north as a warm front
later today and into tonight with low pressure ejecting east out of
the Upper Midwest region. As a result, our area will be open for
business with a steady dose of moist southwesterly flow feeding in.
Meanwhile weak upper level ridging at 500 mb will build into the
region tonight and for the first half of Wednesday allowing rain
chances to decrease. Rain chances do return for some during the
second half of although coverage once again will be isolated.
The 12z NAMnest, HRRR, and ARW illustrate the potential for
prefrontal shower activity Wednesday afternoon and evening as a
piece of shortwave energy races ahead of the front. Did take this
into account with 15 to 30 percent PoPS confined to southeast West
Virginia and the Alleghany Highlands Wednesday afternoon and
evening. Also left a mention of thunder in for the mountains
Wednesday afternoon since enough instability looks to be generated
from filtered sunshine, warm temps, and increased humidity. Most of
the activity looks to remain in the mountains with lower confidence
for an isolated shower or storm further east Wednesday afternoon.
As for temperatures, we look to remain 5 to 15 degrees above average
through the period. Highs today will be similar to Monday with upper
60s and 70s over the mountains to near 80 further east. Temperatures
will be tapered a bit due to excess cloud cover especially over the
mountains where filtered sunshine may take longer to poke through.
Wednesday will be our warmest day of the next seven days ahead and
will feel more like a day to jump in the pool or float on the river
with highs around 80 degrees. Humidity will also be on the uptick as
dewpoints climb into the mid to upper 50s Wednesday afternoon
Confidence remains high in the near term period. Leaned toward the
ARW and HRRR for cloud cover and precipitation chances today
through Wednesday. Both of these models kept us drier in the
near term as convection flourishes to our south and west. They
also hold mid to high level clouds in longer with better
opportunities for sunshine during the afternoon and evening
hours especially east of the Blue Ridge Parkway.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 235 PM EDT Tuesday...
Showers/few thunderstorms Thursday but still mild.
Seems models are speeding up slightly the fropa Thursday, and this
may impact instability in the east if it clouds up faster.
Still a decent shortwave/vort moving across that morning but overall
am not too impressed with severe chances as better instability will
be south across southern NC into SC, but still enough to warrant
thunder chances mainly east of the Blue Ridge Thu afternoon.
Lingering showers in the piedmont Thursday evening then high
pressure builds in Friday with dry and mild weather.
High pushes to the coast Friday night with return flow ahead of warm
front and approach of another weaker front from the west may bring a
few showers to the mountains by Sat morning.
Warm lows Wed night in the 50s with low 60s east. Highs Thursday
will range from the mid to upper 60s mountains to mid to upper 70s
piedmont.
Cooler behind front but still warmer than normal Thu night with 40s
areawide, then warming back into the 60s and 70s Friday.
Forecast confidence is above average on temps/winds and sky cover
and mainly above average on pops, but average on thunder
chances.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 100 PM EDT Tuesday...
Mostly dry weekend, then chance of showers and turning cooler.
ECMWF/GFS/Canadian have differences again today but are close enough
to give an idea about this period. The weekend overall looks mostly
dry aside for some fast moving shortwaves in westerly flow with
broad trough in place. Saturday looks to be the mildest day with
highs in the 60s in the mountains to 70s piedmont.
Easter Sunday, the trough deepens with high pressure building in
from the north while front stalls out across the Gulf Coast states.
Cannot rule out a few shower in the southwest mountains as inverted
trough sets up, but overall should be pretty good day to be outside
doing an easter egg hunt. After a typical mid April cool start in
the 30s and 40s, temperatures will rebound to the 60s for most, with
50s in the WV mountains.
Monday shows another 5h low/trough pushing across the upper MS
Valley into the TN Valley. Differences exist on the strength of this
system, with the ECMWF the strongest. The front to our south lifts
back north as a warm front while a surface low moves into the Ohio
Valley. Monday could be tricky on highs as rain chances increase
ahead of the warm front and surface high moves off the mid-Atlantic
coast. Have leaned toward the 00z ECMWF in our typical wedge area
from southeast WV to the piedmont of VA north of Danville, with
highs in the 50s, with some 40s along the ridges, while milder
temperatures in the lower to mid 60s reside along/south of the VA/NC
border in the piedmont and in the mid 50s to lower 60s in the
southwest VA mountains/NC mtns.
Given discrepancies in the models still, leaning toward keeping pops
capped at chance 30-50. Using a blend of models, will see a cold
front work across Tuesday. Cooler air may allow for some high
mountain snow showers but at the moment nothing of consequence.
Low temperatures will be close to normal in the 30s mountains to
lower 40s piedmont. Cooler highs Tuesday ranging from he upper 40s
to lower 50s mountains to upper 50s to mid 60s east.
Forecast confidence is average on rain chances early next week and
temperatures, but slightly above average this weekend.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
As of 800 PM EDT Monday...
Mid and high level clouds continue to move through the area.
Conditions at TAF sites have improved to VFR and are expected to
remain VFR through Wednesday morning. Scattered to overcast high
level clouds will return to the area Wednesday, before skies start
to clear Wednesday afternoon.
Overnight, winds will decrease and turn to the south, before
becoming more southwest Wednesday afternoon ahead of an
approaching front. Winds speeds will be between 10 to 20 knots,
with the stronger winds along the higher elevations. Gusty winds
expected Wednesday afternoon and evening, around 15 to 25
knots.
Lingering moisture in the mountains of SE West Virginia may lead to
the development of fog near KLWB Wednesday morning for a few hours.
Otherwise, Wednesday looks to be mostly dry, with some chances
of intermittent showers and storms, mainly west of the Blue
Ridge, in the afternoon and evening hours as the cold front
approaches.
Average confidence for ceilings, visibilities, and wind through
the TAF period. Lower confidence for timing of precipitation
associated with the cold front.
Extended Discussion...
The best opportunity for MVFR to IFR conditions appears to be
on Thursday as a cold front swings through. Precipitation
chances at most of the TAF sites are isolated to scattered, with
higher chances -SHRA/-TSRA at KLWB and KBLF. Expect areas of
MVFR/IFR in -SHRA/-TSRA with LAMP probability guidance
indicating LWB and BLF as the most likely candidates for sub-VFR
Wednesday and Thursday.
The front looks to clear the area Thursday afternoon and evening
with brief high pressure settling in for Friday. Another chance for
sub-VFR conditions is likely a possibility for the weekend
ahead.
The winds shift back toward more of a westerly direction while
still remaining gusty behind the front Thursday. Lighter winds
are expected Friday as high pressure builds in. Another front
looks to cross the area on Saturday, before another round of
high pressure to end the weekend.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...ET
NEAR TERM...ET/AS
SHORT TERM...WP
LONG TERM...WP
AVIATION...AMS/ET/AS
Area Forecast Discussion
National Weather Service San Angelo TX
622 PM CDT Tue Apr 12 2022
...New AVIATION...
.SHORT TERM...
(This evening through Wednesday)
Issued at 222 PM CDT Tue Apr 12 2022
As of 2:30 PM...the dryline was situated roughly along and east
of line from Stamford to San Angelo to Junction line. Scattered
showers and thunderstorms have developed east of the dryline
across our eastern counties. A severe thunderstorm warning has
already been issued on the storm currently in northern Coleman
County. Given the current environment- ML CAPE values of
2000-2500 J/KG and mid level lapse rates of 8 degrees C/KM per
current RAP analysis- additional strong to severe thunderstorms
are possible through the afternoon and evening hours for the far
eastern Concho Valley and Heartland. The bulk of the activity
should exit our county warning area by around 6-7 PM. For tonight
will hold on to a slight chance of PoPs across our far
southeastern counties as a Pacific front moves down into the area.
Otherwise, lows will fall into the upper 50s to mid 60s.
Wednesday will be much cooler compared to today behind the
Pacific front. Highs will be in the upper 70s and 80s. The
combination of very dry conditions (relative humidity values under
10%) and gusty west- northwest winds will lead to another day of
critical fire weather conditions across the entire area.
&&
.LONG TERM...
(Wednesday night through next Monday)
Issued at 210 PM CDT Tue Apr 12 2022
Southerly return flow will build back in on Thursday, which should
allow high temperatures to climb back into the upper 80s and low 90s
by the end of the week. Otherwise, dry weather will persist. Over
the weekend, there are some model differences, as the GFS shows a
cold front coming down into Texas on Saturday, the ECMWF delays this
front until Sunday. High temperatures could range from the mid 70s
to the low 90s over the weekend, but for now, we trended with the
warmer solution, given the dry soil conditions and overall warm
pattern. Regardless, this could include some rain chances for our
southeast counties over the weekend, but models are still struggling
to get a handle on timing and location.
&&
.AVIATION...
(00Z TAFS)
Issued at 621 PM CDT Tue Apr 12 2022
Expect strong west to northwest winds late Wednesday morning and
afternoon with gusts to 35 knots. Otherwise, expect VFR for the
next 24 hours.
&&
.FIRE WEATHER...
Issued at 258 PM CDT Tue Apr 12 2022
A Red Flag Warning remains in effect through this evening for
the Big Country, Concho Valley, and the Northern Edwards
Plateau. Gusty southwest winds combined with minimum relative
humidity values 7-18 percent are resulting in critical fire
weather conditions.
A Fire Weather Watch remains in effect for all of west central
Texas for Wednesday. After passage of a Pacific front early in
the day, gusty west to northwest winds combined with relative
humidity falling below 10 percent will result in critical fire
weather conditions. Wind speeds are expected to be 15-25 mph with
higher gusts.
Elevated fire weather conditions are expected to continue through
the rest of the week, during the afternoon hours. Warm and above
normal temperatures will be combined with relative humidity values
dropping to 6-12 percent Thursday, and 10-30 percent Friday.
Winds will be from the south to southeast on Thursday, and mostly
from the south on Friday. Overall wind speeds will be lower than
what is occurring in the first half of this week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 63 79 44 83 / 10 0 0 0
San Angelo 62 81 44 87 / 10 0 0 0
Junction 62 85 47 88 / 10 0 0 0
Brownwood 61 83 43 85 / 20 0 0 0
Sweetwater 63 76 46 83 / 0 0 0 0
Ozona 60 79 48 86 / 0 0 0 0
Brady 65 82 47 85 / 20 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 9 PM CDT this evening for Callahan-Coke-
Crockett-Fisher-Haskell-Irion-Jones-Nolan-Runnels-Schleicher-
Shackelford-Sterling-Sutton-Taylor-Throckmorton-Tom Green.
Fire Weather Watch from Wednesday morning through Wednesday
evening for Brown-Callahan-Coke-Coleman-Concho-Crockett-Fisher-
Haskell-Irion-Jones-Kimble-Mason-McCulloch-Menard-Nolan-Runnels-
San Saba-Schleicher-Shackelford-Sterling-Sutton-Taylor-
Throckmorton-Tom Green.
&&
$$
SHORT TERM...42
LONG TERM....SK
AVIATION...21