Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/05/22
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
732 PM EDT Mon Apr 4 2022
.SYNOPSIS...
High pressure moves offshore of the Carolina coast by this
evening. Low pressure tracks across the area Tuesday evening
through early Wednesday morning, bringing widespread showers to
the area. A cold front crosses the area on Thursday, with
showers and thunderstorms expected across the local area.
Cooler weather returns from Friday through the weekend.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 320 PM EDT Monday...
Latest surface analysis reveals ~1020mb high pressure in place along
the E NC/SE VA coast. To the west, broad weak low pressure is noted
over the upper midwest to the Mid-Mississippi River Valley, with a
weak warm front arcing to the E-SE ahead of the low. Aloft,
shortwave ridging has briefly nudged into the region, allowing
for a pleasant spring afternoon across the local area.
Meanwhile, to the west, a weak shortwave has emerged from the
southern high plains and will push across OK/TX late today
through this evening.
19z Obs reveal highs in the upper 50s to mid 60s across the area,
warmest across NE interior NC. Expect mid to high clouds to thicken
and lower over western sections late this afternoon into this
evening, eventually spreading east to the coastal plain tonight.
Southern plains shortwave tracks toward the lower Miss River Valley
tonight, with developing sfc low pressure taking shape over the
Ozarks into the Mid-south early Tuesday. Meanwhile, S-SW flow aloft
will nudge warm front toward the local area. As the night
progresses, CAMs are in decent agreement in modeling some weak
mid- level overrunning moisture (well ahead of the main low
pressure system) toward the local area. This will manifest first
in lowering cloud bases across the nrn half of the FA by late
tonight, with some isolated to widely sct showers now appearing
likely over the northern quarter of the area, mainly north of
the RIC metro over to the northern neck and MD eastern shore.
Should continue to note the rather deep, dry sub-cloud layer
that will need to be overcome before pcpn reaches the ground.
However, with several successive runs of the HRRR and majority
of the other 12z CAMs consolidating on placement and QPF, bumped
up rain chances into slight to chance range over northern-most
zones. Lows will range through the 40s.
Bit of a lull in rain on Tuesday, with models seemingly a bit
slower with the moisture return late Tuesday. Initial weak slug
of moisture moves out by midday Tuesday, and we await southern
stream shortwave lifting across the mid-south toward the
southern Appalachians.In between these features, S-SW flow will
bring a milder day across the area, especially central and
southern zones that don`t get in on initial batch of rainfall.
Highs Tuesday in the lower to middle 60s, MD coastal zones, mid
60s to near 70 north, low to mid 70s central and south.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 320 PM EDT Monday...
Rain chances then ramp up quickly tomorrow night in association
with the quick-moving southern stream shortwave trough. Entire
area is still on track for a period of widespread showers Tue
evening into early Wed AM. Theta-e ridge lifts across the area
around and just after midnight Tue night/Wed morning, before
pushing offshore by mid-morning Wed. PWs rapidly increase to
1.3-1.7" during this period late Tue evening area wide, with
best moisture transport...and most of the pcpn...still modeled
to occur on the cool side of a subtle warm frontal boundary
which will be oriented to the south of the local area through
dawn Wed morning.
With respect to the convective threat, best lift still appears
to remain confined well to the south of the region from GA into
the western Carolinas Tuesday night, closer to the true warm
sector. Given the late night timing and little to no sfc-based
instability making it to the FA until the boundary moves N of
our area and pcpn ends, still primarily be concerned with
locally heavy rainfall over our area. The onset of moderate to
occasionally heavy pcpn will be from 6-10 PM across the wrn half
of the FA and 8 to midnight near the coast. Warm cloud depths
increase to 3-4km during this period, again portending a period
of moderate to perhaps briefly heavy rainfall. WPC has
continued a Marginal Excessive Rainfall Risk area over our
southern half of the area, highlighting potential flash
flooding of urbanized or flood prone areas. Despite minimal
severe threat locally during this time range, we`ll likely see
a few rumbles of thunder across at least the S half of the FA
Tue night. Will maintain categorical (80-100%) PoPs and have
QPFs of 0.50 to 1.00" area wide.
Mild Tue night with lows in the 50s to low 60s, which will be
achieved by 06z/2 AM Wed before temperatures steady then rise
slightly during the latter part of the night. There will be
rapid clearing on Wednesday, as the aforementioned warm frontal
boundary lifts north across the area and the system quickly
moves well offshore. This will result in warm temperatures (and
a brief period of dry wx) throughout much of the area for
Wednesday. Forecast highs are in the upper 70s-low 80s from
central VA to NE NC, with low-mid 70s from the Ern Shore to the
VA Nrn Neck.
Model timing of the frontal passage seems to have also slowed
with 12z suite of models. Expecting mainly variable clouds and
mild Wed night, with the slight chance of some showers over the
piedmont toward morning as front approaches from the west. Lows
in the 50s to low 60s.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 320 PM EDT Monday...
The late week period continues to be characterized by broad,
deep upper low dropping across the eastern-third of the CONUS,
with an equally deep upper ridge building just east of the
Rockies, extending north into the Canadian Prairies.
Mild to begin the day Thu. The amplifying upper trough will
push a reasonably strong cold front across the region late in
the day on Thu into Thu evening. Showers (and possibly isolated
tstms) will begin around or just after sunrise Thursday morning
along and west of I-95, with showers/tstms developing and/or
moving into eastern portions of the FA by aftn as the front
begins to cross the area. Enough in the way of deep layer shear
and developing CAPE, especially over eastern sections to monitor
potential severe threat for Thursday afternoon. Showers/tstms
should quickly end from WNW-ESE from Thursday evening through
the first part of Thursday night as the cold front pushes
offshore.
The trough axis aloft pushes into the ern CONUS by Fri,
bringing persistent clouds and a cooler (though still mild) end
of the work week into next weekend. Isolated to widely
scattered diurnally-driven showers expected on Fri/Sat with the
trough axis/cold pool aloft lingering near or over the area.
Finally by Monday, upper low ejects offshore, with a marked
warmup ensuing across the region, as deep upper ridge over the
central CONUS finally builds east.
Highs Thu in the mid 60s- near 70F NW to the mid-upper 70s in
SE VA-NE NC. Highs Fri mainly in the 60s, with upper 50s-low 60s
on Sat/Sun. Lows Thu night in the mid 40s-mid 50s, with upper
30s-40s Fri night, and mid 30s- mid 40s Sat night. Highs Monday
into the upper 60s to mid 70s, with warmer readings likely as we
head toward the middle of next week.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
As of 730 PM EDT Monday...
VFR conditions will likely persist through 00z Wednesday for
areas south and west of the Chesapeake Bay. Light southerly
winds tonight with high pressures centered east of the Outer
Banks. Increasing mid to high clouds moving in this aftn into
later tonight. CIGs fall to 6-9kft AGL tonight with iso to sct
showers from RIC to SBY well after midnight into Tue morning.
MVFR conditions are expected for Delmarva tomorrow. Winds at
KSBY will become ENE as a warm front develops across VA
tomorrow. Fog is possible tomorrow evening across the Eastern
Shore with the nearby warm front.
Outlook...Unsettled wx returns by early Tuesday evening. Low
pressure tracks across the area late Tue-Wed AM, with widespread
showers expected, along with a few tstms (best tstm chances are
at ORF/ECG). Periodic sub-VFR conditions are likely in heavier
showers/isolated tstms Tuesday night into Wednesday. Improving
conditions are expected by late Wed AM behind the departing
system. However, the next system quickly brings another period
of potential sub-VFR conditions from Thu aftn-Friday.
&&
.MARINE...
As of 340 PM EDT Monday...
High pressure was centered over the local waters this afternoon with
winds generally light with an onshore flow of 5-10 kt except S 10-15
kt across the northern coastal waters. SE/S winds increase to 10-15
kt late this afternoon/tonight as the high slides offshore. Some of
the high res CAMS hint at a brief period of 15-20 kt winds with
gusts 20-25 kt tonight. However, NBM probs are only 20-30% for
sustained winds 18 kt. Therefore, will refrain from issuing SCAs for
tonight at this time given low confidence. Winds become S 10-15 kt
late tonight.
Low pressure moves ENE across the Lower MS Valley into the southern
Appalachian mnts tomorrow before continuing ENE through the local
waters tomorrow night. As a response, WAA will ramp up with S/SSE 10-
15 kt tomorrow increasing to 15-17 kt across the Ches Bay and 15-20
kt across the coastal waters by late afternoon. Winds continue to
increase to 15-20 kt across the Ches Bay, Lower James, Currituck
Sound and northern coastal waters and 20-25 kt across the southern
coastal waters tomorrow evening/night ahead of the low. Gusts to 25
kt will be possible across the Ches Bay, Currituck Sound, and
northern coastal waters with gusts to 30 kt possible across the
southern coastal waters. SCAs have been issued for the Ches Bay,
Currituck Sound, and coastal waters from 6 PM tomorrow until 6 AM
Wed and from 10 PM tomorrow until 6 AM Wed for the Lower James due
to elevated winds and waves/seas. Elevated seas could linger through
Wed afternoon for the southern coastal waters and through Wed
evening/early Wed night for the northern coastal waters. However,
given 6 AM Wed is the end of the fourth period, will end all SCAs at
that time for now and extend SCAs as needed once we get closer to
the event.
As the low pushes ENE offshore late tomorrow night, winds become SW
15-20 kt, becoming W late. W winds 10-15 kt Wed morning become NW/N
5-10 kt Wed afternoon, becoming NNE late as high pressure briefly
builds in. Low pressure occludes over MN/WI Wed, gradually moving E
towards the Great Lakes Thurs. The occluded/cold front spawns a sfc
low over W NC Wed night that moves NE across VA Thurs, eventually
crossing N of the local waters Thurs evening. Winds become E 10-15
kt Wed night, becoming SE Thurs morning, and S by Thurs afternoon.
Winds become NW behind the front Thurs evening/night but are
expected to remain sub-SCA at this time due to weak CAA.
Waves of 1-2 ft build to 2-3 ft tomorrow afternoon, eventually
building to 2-4 ft tomorrow evening/night. Waves subside to 1-2 ft
Wed afternoon. Seas of 2-3 ft build to 3-4 ft tomorrow afternoon,
eventually building to 4-6 ft tomorrow night into Wed. Seas subside
to 3-4 ft Wed afternoon across the southern coastal waters but
linger at 4-6 ft through Wed evening/early Wed night across the
northern coastal waters.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory from 6 PM Tuesday to 6 AM EDT Wednesday
for ANZ630>634-650-652-654-656-658.
Small Craft Advisory from 10 PM Tuesday to 6 AM EDT Wednesday
for ANZ638.
&&
$$
SYNOPSIS...ERI
NEAR TERM...MAM
SHORT TERM...ERI/MAM
LONG TERM...ERI/MAM
AVIATION...CP/MAM
MARINE...RMM
Area Forecast Discussion
National Weather Service Denver/Boulder CO
901 PM MDT Mon Apr 4 2022
.UPDATE...
Issued at 842 PM MDT Mon Apr 4 2022
Radar shows snow showers beginning to develop over the higher
elevations this evening. Showers will continue to develop and
increase in coverage in the mountains overnight. As anticipated,
winds are increasing over the higher elevations as cross barrier
flow gradually increases aloft. No major changes were made to the
forecast. Could see some areas of blowing dust in the more dry
areas of the eastern plains tomorrow afternoon given high winds.
The previous Fire Weather Watch issued for the northeastern
Colorado plains and Palmer Divide tomorrow has been upgraded to a
Red Flag Warning. RH values will be near-critical to critical
combined with high winds.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 312 PM MDT Mon Apr 4 2022
Though the weather is quiet this afternoon across the forecast
area, a dynamic weather system is set to arrive tonight and
continue tomorrow. Multiple headlines are now in effect for the
mountains, Foothills, and plains over the next 24 hours.
RAP Mesoanalysis this afternoon shows a belt of 100+kt 500mb flow
over Oregon this afternoon, with a compact upper level low
spinning across the Pacific Northwest. This upper low will shift
across the US/Canadian border through tomorrow, with strong
westerly flow aloft spreading across Colorado tonight and
tomorrow. Moisture will gradually increase across the high country
overnight tonight, and orographic snow showers will develop after
sunset and continue through the night. Though snow accumulations
will be generally a few inches... the combination of snow and
strong wind gusts will lead to hazardous travel. Snow and blowing
snow will continue through much of Tuesday before tapering off.
Total snow accumulations of 5 to 10 inches of snow will be
possible across the mountains above 9000 feet.
Very strong wind gusts are also set to develop this evening across
the Foothills as a mountain wave develops. The mountain wave
itself doesn`t look particularly impressive, but a modest stable
layer near ridgetop and cross-barrier flow near 50-60kt should be
more than enough to get a few gusts in the 70-80mph range. The
High Wind Warning for the foothills is set to begin at 6pm and is
well supported by the HRRR and the rest of the HREF suite.
By tomorrow, we`ll see strong winds spread into the plains behind
a weak cold front. The far north/northeast plains have been
upgraded to a High Wind Warning where guidance shows better
agreement in at least a few 60-65mph gusts through the afternoon.
There is less certainty in the high wind potential for the Denver
metro, which will be displaced from the strongest mid-level flow
and subsidence. Thus we`ve left the High Wind Watch there and will
punt one more time to the overnight crew. With the high wind also
comes dry air, and elevated/near critical fire weather conditions
are also looking more likely. More details on that in the fire
weather section below.
.LONG TERM...(Tuesday night through Monday)
Issued at 253 PM MDT Mon Apr 4 2022
Tuesday night through Thursday, a deep upper level low pressure
system will be centered over the Northern Great Lakes Region with an
upper level ridge over the Western U.S. Colorado will lie in-between
these two systems under the influence of a strong northwesterly flow
aloft. A strong surface pressure gradient between higher pressure
over the Central Plains States and lower pressure over Colorado,
combined with moderate to strong winds aloft and plenty of
subsidence should lead to continued breezy to windy conditions
across the CWA. The strongest winds should be on Wednesday with the
potential for damaging winds across the far northern and eastern
sections of the plains. Will need to keep a close eye on this as we
may need to issue high wind products for these areas. With limited
moisture available, dry conditions are expected. The exception will
be scattered snow showers mainly over the North Central Mountains
with some light accumulation over the higher peaks mainly Tuesday
night into Wednesday morning.
Friday and Saturday, the large upper level storm system over the
Great Lakes is progged to weaken and shift eastward into the Eastern
U.S. This will allow a large ridge of high pressure to move across
the Rocky Mountain Region bringing warmer temperatures, less wind
and very dry conditions to the forecast area.
For Saturday night through Monday, ensemble and deterministic models
are showing an upper trough deepening over the Western U.S. with a
moderate west southwesterly flow aloft over Colorado. Increased
moisture and orographic flow associated with this pattern should
bring another round of snow to the high country. Further east across
the plains there is some uncertainty due to discrepancies between
the ensemble and deterministic solutions. Some of the deterministic
models, such as the GFS, suggest a cold front moving across
Northeastern Colorado Sunday night into Monday which could bring
cooler unsettled conditions to the plains and some relief to the
fire danger. For now, the consensus is for mostly dry, mild and
breezy conditions to continue through the period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 607 PM MDT Mon Apr 4 2022
VFR conditions are likely to continue tonight and Tuesday. Winds
return to light SSW/SW drainage this evening. High winds develop
in the foothills overnight which may edge into BJC for periods
overnight with gusts 25-35 kts. Confidence isn`t high in the
timing and duration of these gusts, but become more likely after
09z. A cold front shifts winds north Tuesday morning with a push
of increased winds. Stronger WNW winds become more likely in the
afternoon with gusts in the 30-40 kt range. BJC and potentially
APA will see an earlier onset of higher gusts (mid/late morning).
&&
.FIRE WEATHER...
Issued at 253 PM MDT Mon Apr 4 2022
UPDATE...
855 PM MDT Mon Apr 4 2022
Near critical to critical conditions remain likely across the
plains and Palmer Divide Tuesday. Relative humidity values still
look marginal, as previous mentioned. However, given the high wind
conditions the previous Fire Weather Watch has been upgraded to a
Red Flag Warning for the northeast plains and Palmer Divide.
Near critical to critical fire weather conditions are expected
across the plains and Palmer Divide Tuesday and Tuesday evening.
Gusty winds up to 60 mph will combine with dry conditions across
the forecast area. With little precip falling in the past 14
days... especially across the plains north of I-70... have opted
for a Fire Weather Watch despite marginal RHs. It is also possible
that our current RH forecast is too high, especially based on
observations this afternoon across portions of the urban corridor.
Regardless of if conditions meet Red Flag Criteria, any fire start
will certainly have the potential to spread rapidly Tuesday.
Persistent breezy to windy conditions combined with low relative
humidity will result in near critical to critical fire danger across
portions of the Foothills, plains and Palmer Divide through much of
the period. The windiest conditions are expected on Wednesday with
the relative humidity ranging from the lower teens over Southern
Lincoln County to mid 20s across the far northeastern zones. Winds
will gradually decrease through the end of the week with with
relative humidity values dropping to the teens across all of the
plains.
On Saturday, humidity values are expected to drop further with
increasing winds ahead of another storm system. We may see some
relief of the fire danger across portions the plains Sunday and
Monday as cooler temperatures and higher humidity moves into the
region. However, the cooler, more moist air may not reach the
Southern Foothills, Palmer Divide and Southern Lincoln County.
Therefore, these area may continue to see near critical to critical
fire weather conditions through this period
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
High Wind Warning from 9 AM to 9 PM MDT Tuesday for COZ038-
042>044-048>051.
Red Flag Warning from 11 AM to 9 PM MDT Tuesday for COZ238>251.
High Wind Warning until 9 AM MDT Tuesday for COZ035-036.
Winter Weather Advisory until midnight MDT Tuesday night for
COZ031-033-034.
High Wind Watch from Tuesday morning through Tuesday evening for
COZ040-041-045-046.
&&
$$
UPDATE...
SHORT TERM...Hiris
LONG TERM...Kalina
AVIATION...Mensch
FIRE WEATHER...Hiris/Kalina
Area Forecast Discussion
National Weather Service Charleston SC
1024 PM EDT Mon Apr 4 2022
.SYNOPSIS...
High pressure will prevail today. A series of low pressure
systems will impact the region through the middle of the week.
Drier and cooler weather is expected to return late week
through the weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Quiet conditions late this evening, with some of the last
images of the sea breeze on radar showing that it cleared the
final part of the forecast counties around 930 PM as it
continues to move inland.
A warm front in the Gulf of Mexico and over southern Florida will
lift steadily north through the night and reaching into the
forecast counties well after midnight. Meanwhile, our expected
severe weather system for Tuesday afternoon and evening is
gaining strength in Texas and Oklahoma, with a surface low to
form near the Arklatex. Convection in and near that low will
develop into an MCS, with the leading edge reaching Mississippi
by daybreak.
For the late evening update we didn`t make any changes to the
coverage of the patchy fog, which is generally near and west of
I-95 after 3 or 4 AM. This remains similar to what the HREF and
HRRR would suggest are the most favorable locations, where we
find the lowest condensation pressure deficits and Fog Stability
Indices. At this time the fog doesn`t look to be too significant
given 15-20 kt geostrophic winds and the pre-existing dry
conditions.
Other than few to scattered thin cirrus, and few to scattered
late night stratocumulus/stratus, skies will be no worse than
mostly clear or partly cloudy.
There are hints of a few showers over the Charleston County
Atlantic waters. But even if they do form, the steering flow
would keep them offshore.
Although temps won`t be anywhere near as cool as last night due
to the onshore flow associated with high pressure off the coast
of North Carolina, we did lower some temps in the Francis
Marion National Forest, where the coolest temps in the lower
50s will occur. The warmest will be along the immediate coast
and in downtown Charleston, where the lower 60s will be common.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
Tuesday: The weather should be active with the approach of a h5
shortwave ejecting rapidly across the region well ahead of a parent
longwave trough digging across the Central United States. Ahead of
this feature, deep moisture combined with isentropic lift should
maintain a fair amount of clouds across the area, but warm air
advection within a southerly sfc wind should allow sfc temps to peak
between the upper 70s/lower 80s, warmest inland and across southeast
Georgia. These temps should lead to a fair amount of mixing into a
low-lvl jet (50-60 kt), favoring breezy winds during the day (gusts
around 25 mph). There could even be a period of Lake Wind Advisory
conditions near the shore of Lake Moultrie late day.
Latest guidance suggests a line or cluster of showers/thunderstorms,
some of which could be severe during the afternoon/evening hours
with the arrival of enhanced forcing at the time of an environment
marked by strong shear (~50 kt 0-6km bulk shear, +300 m2/s2 0-3km SR
Helicity, and 50-70 kt low/mid lvl jets under an increasingly
favorable left front quadrant of a 120 kt upper lvl jet) and modest
instability with mid 60 dewpts and SBCAPE approaching 1200-1500
J/kg. Best chances for strong/severe thunderstorms should be along
and west of I-95 in southeast South Carolina, but even more likely
across southeast Georgia where mid-lvl lapse rates and lifted index
values are more favorable for severe weather, especially in regards
to tornadoes. Damaging winds look to be the primary concern, but a
few tornadoes are also possible within a QLCS and/or within storms
that develop ahead of any line/cluster where sfc winds remain south-
southeast within a higher instability environment before precip
activity advances into the region. The SPC has also outlooked the
entire area under an Enhanced Risk of severe weather, including a
hatched area of 10% tornado probability, suggesting the potential
for a strong tornado across parts of southeast Georgia. Severe
Thunderstorm and/or Tornado Watches could eventually be needed
tomorrow afternoon and/or evening. Additionally, some thunderstorms
could produce brief heavy rainfall given PWATs near 1.75 inches
during the period, which could lead to localized minor flooding in
low-lying and poor drainage locations. Overnight, precip coverage
appears more widespread and the severe weather threat could linger a
few hours after sunset given substantial shear to hold
storms/rotating updrafts together, but the loss of sfc instability
should trend toward sub-severe convection, especially approaching
midnight. Lows should remain mild, ranging in the low-mid 60s.
Lake Winds: Conditions will be close to Lake Wind Advisory
thresholds Tuesday afternoon and evening. Since convection could
alter the synoptic pattern, we opted not to hoist an advisory
at this time.
Wednesday: A warm front should be positioned north of the region
early well ahead of a cold front associated with a longwave trough
advancing across the Midwest. Conditions will be unsettled as the
area remains warm sectored through much of the day/evening. Highs
should approach the lower 80s for most locations away from the
immediate coast. Latest guidance suggests showers/thunderstorms
developing upstream and advecting into the area during evening and
overnight hours as the cold front approaches the local area late.
Some thunderstorms could be strong and/or severe while traversing
southeast South Carolina and southeast Georgia, but overall coverage
appears less than the previous day. Damaging wind gusts would be the
primary concern. The SPC currently has much of the local area under
a Slight Risk. The threat of severe weather will come to an end once
fropa nears late. Temps should remain mild for much of night, only
dipping into the mid/upper 60s.
Thursday: The cold front is anticipated to shift offshore within a
few hours of daybreak, shifting the bulk of moisture offshore as low-
lvl winds begin to turn more west-southwest during the afternoon.
Scattered showers along with a few thunderstorms are possible during
morning hours, before shifting offshore across coastal waters. High
temps should peak early and warmest for locations along and east of
I-95 (upper 70s to lower 80s) before the onset of cold air advection
post fropa mid-late afternoon.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Models are in good agreement in the long term period. A high
amplitude mid level trough will encompass the Eastern CONUS Friday
into Saturday, before the main trough axis slides offshore on
Sunday. At the surface, a large area of low pressure will lift over
the Northeast, followed by high pressure expanding into the region
later in the weekend. Dry weather is expected. Temperatures will be
cooler than normal.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Conditions will remain solidly in the VFR category the first
part of tonight, with some chances for light fog/ground fog
late tonight through about daybreak Tuesday. At this time the
better chances look to stay inland from KCHS, KJZI and KSAV.
A robust storm system will be racing across Mississippi,
Alabama during Tuesday morning, reaching into the local area
during the later part of the afternoon and evening. In advance
of this system, S to SE winds will steadily increase during the
morning, then become strong and gusty, especially for the
afternoon. Sounding profiles support winds at least 15-20 kt
sustained, with gusts of 25-30 kt after 16Z.
Isolated to scattered showers will be around the area in the
afternoon, but the bulk of the deeper convection, which could be
strong or severe, arrives late in the valid 00Z TAF cycle. For
now we show low end VFR ceilings and VCTS from 22-24Z. It is
highly likely that conditions will be sub-VFR at some point late
Tuesday and Tuesday evening. But these refinements will be
addressed in future TAF issuances.
Extended Aviation Outlook: At least occasional flight
restrictions are possible in showers/thunderstorms from Tuesday
night through Thursday morning. Gusty winds are also possible
on Tuesday (20-25 mph) at all terminals. VFR Conditions are
expected Thursday night through Friday.
&&
.MARINE...
The forecast area will remain between high pressure centered over
the western Atlantic and low pressure centered over the
Arklatex and lower Mississippi River Valley. Sfc winds will
continue to veer to the SE at speeds generally 10 to 15 kt or
less. Seas will gradually build to 2-4 ft as a warm front lifts
into the waters after midnight. Other than maybe a few showers
brushing into the AMZ350 waters late, no rainfall is expected
through the night.
Tuesday through Saturday: Winds and seas will increase Tuesday into
Tuesday night ahead of low pressure tracking across the Lower
Mississippi River Valley. Small Craft Advisories will likely be
needed for at least a portion of local coastal waters, mainly
northern SC waters and offshore Georgia waters by Tuesday night.
However, the Charleston Harbor could see gusts up to advisory levels
late in the day as well as low-lvl mixing occurs across land. In
addition to stronger gradient winds, a line of showers and
thunderstorms will likely impact the waters Tuesday late afternoon
and evening. Storms could be strong and necessitate Special Marine
Warnings for severe winds and/or waterspouts. Conditions are
expected to improve a bit on Wednesday. Winds will then increase
Thursday ahead of and behind a cold front. Another round of Small
Craft Advisories is possible Thursday, then again during the weekend
on Saturday.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
NEAR TERM...
SHORT TERM...DPB
LONG TERM...DPB
AVIATION...
MARINE...
Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
1036 PM CDT Mon Apr 4 2022
.UPDATE...
The isolated storms in Mexico have waned. A few convective allowing
models suggest some re-development across Mexico, the Rio Grande
Plains, and Winter Garden regions through the overnight. Farther
east and north, convection has been almost non-existent across the
CWA. AMDAR soundings the past hour out of AUS indicate the cap has
eroded, but not at SAT. SPC mesoanalysis reveals a pocket of no CIN
around Austin, so we will see how far south convection along the
boundary to the north can build. 00Z convective allowing models are
not indicating this will happen. Overall, we have lowered PoPs for
the remainder of tonight for most areas.
Finally, some of the 00Z convective allowing models are now
regenerating convection Tuesday afternoon ahead of the boundary
across the far southwest CWA, into the Winter Garden and Brush
Country. This will be looked at further by the mid shift. Should this
occur, we will have to watch for the potential for some downbursts
producing strong wind gusts given the very hot temperatures and
inverted V forecast soundings producing high DCAPE values in this
area.
&&
.FIRE WEATHER...
We have upgraded the Fire Weather Watch for Tuesday to a Red Flag
Warning and expanded into portions of the northern Hill Country.
While sustained winds might not be meeting criteria, the every low
humidity, wind gusts forecast, and recent fire activity and behavior
in this region on similar weather days suggests a Red Flag Warning
is warranted. Red Flag Warnings are also likely across larger
portions of the area Wednesday through Friday.
&&
.PREV DISCUSSION... /ISSUED 646 PM CDT Mon Apr 4 2022/
UPDATE...
Convection developed across Mexico late this afternoon, and a recent
supercell split has produced a left mover that is impacting portions
of southern Val Verde County with a large hail threat. There is
lower confidence on whether the right movers make it across the
border, however additional upstream convection is possible through
the remainder of the evening hours and into portions of the overnight
along the Rio Grande and across the Winter Garden region as better
large scale forcing and streak wrap into the region. We have updated
to explicitly include a mention of severe along the Rio Grande.
Farther east confidence in convective potential remains much lower,
largely driven by the cap still in place seen on the last hours AMDAR
soundings out of AUS and SAT. Recent runs of the HRRR do not suggest
much development east into the Hill Country and I-35 corridor
tonight. We will continue to monitor trends.
AVIATION (00Z TAFs)...
VFR conditions prevail across South Central Texas. We are tracking
supercells across Mexico, with one split taking place and the left
mover approaching the vicinity of DRT. Large hail is likely occurring
in this storm. TSRA has been indicated in the DRT TAF through 03Z.
Confidence remains low on coverage of additional TSRA activity late
this evening and overnight farther east given the cap in place. We
will monitor trends through the evening for possible amendments to
the SAT and AUS TAFs, but at this time due to the low confidence we
have not included TSRA. Otherwise, MVFR ceilings developing 02Z-04Z
along and east of I-35 and I-37, lower to IFR 04Z-07Z and expanding
west into portions of the Hill Country.
PREV DISCUSSION... /ISSUED 338 PM CDT Mon Apr 4 2022/
SHORT TERM (Tonight through Tuesday Night)...
Latest surface observations and visible satellite photos show
abundant moisture across the area this afternoon. As of 3 PM, dew
point temperatures are in the 60s over most areas and up to the
lower 70s to the east of Interstate 35. Area Doppler radars have
been picking up on light to moderate showers since late this morning
where deeper moisture resides. The shower activity is expected to
continue for the rest of this afternoon and evening with
thunderstorm activity also increasing later this afternoon as the
cap weakens.
The scenario for late this afternoon and evening depends on how
quickly the cap erodes across the warm sector, and how far east the
dryline advances between northeast Mexico and Val Verde County. In
addition to all that, an upper-level short wave across the four
corners region is forecast to push east and into the Southern Plains
through the period to support strong to severe thunderstorms across
the area, especially over the Hill Country.
Earlier HiRes model runs were indicating convective initiation
across central Texas ahead of the dryline and pushing a line of
storms to the southeast. However, for the last several runs of the
HRRR, strong to severe thunderstorms have been depicting activity
crossing the international border between 5 and 6 PM with no cap in
place and MLCAPE values in the 1700 and 1800 J/kg range. Also, mid
lapse rates are coming in around 6 and almost 9 C/Km for a
moderately unstable atmosphere. On top of that, effective shear is
coming in around 60 knots. With all these ingredients in place and
if the HRRR pans out, expect storms to develop quickly and become
strong to severe with the main hazards being damaging winds and
large hail. Can`t rule out an Isolated tornado or two. Otherwise,
this is a low confidence event as models are having difficulties on
sharing a unified solution.
Once the activity pushes to the east of our area on Tuesday, all
eyes turn to fire weather concerns as dry air and breezy conditions
take place as the dryline pushes into the Hill Country and the Rio
Grande. We have opted to issue a Fire Weather Watch for Val Verde,
Edwards, Real and Kinney Counties from 1 PM through 7 PM Tuesday.
The other item of concern during the day on Tuesday will be the hot
temperatures with record highs expected for a lot of areas. Highs
will range from the lower to mid 90s across the Hill Country near
100 across the Rio Grande. See more details in the climate section.
LONG TERM (Wednesday through Monday)...
A cold front will make steady southward progress across the region
on Wednesday. Gusty north winds will spread in behind the front,
along with cooler temperatures. The coolest readings are anticipated
across the Hill Country where highs will peak in the mid to upper
70s. Farther south into the Rio Grande and coastal plains, highs will
still manage to warm into the upper 80s to lower 90s as a stout low-
level thermal ridge will still be in place. Some moisture will be in
place across the coastal plains just ahead of the front. Confidence
in precipitation along the front is low, so we will keep the forecast
dry at this time. A reinforcing shot of surface high pressure moves
in on Thursday and this will keep highs down in the 70s to near 80.
Surface winds finally ease Thursday night into Friday morning. With
winds decreasing and dry air and clear skies in place, overnight lows
will drop into the upper 30s to upper 40s across most areas. We can`t
completely rule out some lower to mid 30s in wind sheltered/low-
lying areas across the Hill Country. Highs on Friday will again range
from the mid 70s to lower 80s, with another cool night in store
Friday night into Saturday morning. A few of the models show return
southerly flow kicking in a little sooner on Saturday. This could
alter the low temperature forecast for Friday night into Saturday
morning. For now, we will show most areas in the upper 30s to upper
40s.
Southerly flow in the low-levels quickly ramps up for the upcoming
weekend into early next week, resulting in a warming and moistening
trend. We will keep the forecast dry through the weekend given the
fairly stable northwest flow aloft. By late Sunday into early Monday,
there are signs the flow aloft transitions to the southwest. For now,
we will only mention a slight chance for showers along the Highway 77
corridor into portions of I-35 on Monday.
FIRE WEATHER...
Elevated to critical fire weather conditions and opportunities for
Fire Weather Watches and Red Flag Warnings return on Tuesday and
continue through Saturday. By the way and as mentioned above, there
is a Fire Weather Watch for the northwest of the area from 1 PM to 8
PM Tuesday for low humidities and breezy conditions. Minimum
humidities will plunge into the single digits and teens across our
western areas on Tuesday and Wednesday, then continue through
Saturday. Minimum humidities in the 20s and 30s across our eastern
areas on Tuesday and Wednesday, also plunge into the single digits
and teens on Thursday, then continue through Saturday. Humidities
recover a little on Sunday. Winds will be breezy and gusty most
days. Westerly winds on Tuesday turn northerly on Wednesday and
Thursday, then turn southerly out west on Friday and all areas on
Saturday. Any wetting rains from showers and thunderstorms today and
tonight will be spotty and will likely not contribute to any fuel
moisture. As a result, fuels are expected to dry even more during
the next several days.
CLIMATE...
Record High Temperatures for April 5
Austin Camp Mabry 94
Austin Bergstrom 89
San Antonio 93
Del Rio 96
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 65 93 62 79 52 / 20 0 0 0 0
Austin Bergstrom Intl Airport 64 92 60 80 49 / 20 0 0 0 0
New Braunfels Muni Airport 66 94 60 84 50 / 20 - 0 0 0
Burnet Muni Airport 60 92 58 77 48 / 20 0 0 0 0
Del Rio Intl Airport 63 99 62 89 55 / 20 0 0 0 0
Georgetown Muni Airport 62 92 60 78 50 / 20 0 0 0 0
Hondo Muni Airport 63 97 59 89 49 / 20 - 0 0 0
San Marcos Muni Airport 64 93 60 82 49 / 20 - 0 0 0
La Grange - Fayette Regional 69 90 63 81 50 / 20 - 0 0 0
San Antonio Intl Airport 66 94 62 84 53 / 20 - 0 0 0
Stinson Muni Airport 69 97 65 89 55 / 20 - 0 0 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 1 PM to 8 PM CDT Tuesday for Bandera-Edwards-
Gillespie-Kerr-Kinney-Llano-Real-Uvalde-Val Verde.
&&
$$
Short-Term/Aviation...76
Long-Term...KCW
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
757 PM EDT Mon Apr 4 2022
.SYNOPSIS...
Dry and mild high pressure will slide east of the area tonight.
A strong low pressure system with plenty of moisture is expected
to move over the area Tuesday afternoon and evening. A strong
cold front will then cross the western Carolinas early Thursday,
bringing well below normal temperatures through the end of the
week.
&&
.NEAR TERM /THROUGH TUESDAY NIGHT/...
As of 741 PM EDT Monday: Current fcst remains on track with high
clouds moving overhead. Radar shows some light returns that should
brush past the nrn mountains this evening, but nothing is expected
to reach the ground. No changes.
Otherwise, dry weather will continue tonight as high pressure
slides offshore and a low-level return flow gradually builds into
the region. High clouds will increase overnight, ahead of a potent
shortwave that will cross the Southern Plains and enter the Lower
MS Valley by daybreak Tuesday. Deep layer southwesterly flow will
filter WAA into the region, ahead of the shortwave and allow for
lows tonight to remain slightly above normal for most locations.
The shortwave will traverse into the southeastern CONUS mid-morning
Tuesday with a stout low pressure system riding underneath. Strong
upper divergence aloft from the southern stream jet and strong
low-level isentropic lift will only enhance the dynamics of this
system by providing an abundance of forcing as the low pressure
system enters the CFWA by the early afternoon hours across the
southwestern zones. Strong 35-45 kt south to southwesterly LLJ
on the leading edge of the system will surge deep moisture from
the Gulf of Mexico and Atlantic into the CFWA just as the brunt
of the system arrives at our doorstep. In response, PWAT values
will rapidly reach 1.0"-1.5+" across the entire CFWA, with the
highest values overlaying the southeastern zones. In this case,
expect for heavy rainfall rates as the system slides across the
CFWA Tuesday afternoon/evening, especially across the southern Blue
Ridge Escarpment where favorable upslope enhancement will be in
store. Model guidance indicated a wedge boundary to develop as the
system pushes into the region. This should help provide more stable
air on the north side of the boundary which will ultimately limit
instability. Strong deep layer shear and high SRH values suggest
that if enough forcing can overcome the lackluster instability,
the potential for QLSC development can`t be ruled out Tuesday
evening into Tuesday night as the frontal boundary associated with
the low pressure system moves into the area. Thus, a low-end severe
threat will be present with this system, but has potential to bust
as hi-res models indicate a deep MCS to move across the Deep South,
which could lower QPF amounts and the overall severe threat as the
deeper moisture and instability could have trouble transporting
this far north. Still expect widespread rain to move across the
CFWA from the southwest to the northeast, but the shortwave is
expected to zoom across the area, so any hydro threat will be
limited. Isolated flash flooding will be possible in flood prone
areas. Max temperatures will be near normal Tuesday.
Expect the system to push out of most locations by midnight Tuesday
as a dry slot gets punched into the region. The HRRR has suggested
a few discrete cells developing on the back end of the system with
some available surface based instability as the frontal boundary
crosses the CFWA. This is possible as the wedge boundary likely
becomes eroded after the brunt of the system leaves the area. This
could prolong the severe threat through the evening hours on
Tuesday. Otherwise, most locations will become dry Tuesday night
with clouds slowly scattering out as drier air advects into the
region. Temperatures Tuesday night will remain 5-10 degrees above
normal due to deep layer WAA southwesterly flow still in place.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
As of 235 PM EDT Monday: The short-term fcst picks up at 12z on
Wednesday with an embedded upper shortwave lifting off the Atlantic
Coast as a large, closed upper low/ trof digs southward over the
Central CONUS. For the rest of the period, the upper low/trof will
gradually push farther south and east and into our area.
At the sfc, a robust cold front will move into the area late Wed/
early Thurs. With deep-layer SWLY flow still in place and the area
under the warm sector ahead of the front, more sfc-based instability
is expected. Shear and helicity will increase again as the front
moves in with another low-lvl jet expected to move over the CWA.
A QLCS line may develop over our area with the front, along with
discrete or semi-discrete cells given the better instability.
This scenario remains in line with the Day 3 Enhanced convective
risk over the western portion of our CWA and the Slight risk over
the rest of our CWA.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 215 PM EDT Monday: The extended forecast picks up at 00z on
Friday with a large, closed upper low/trof digging southward over
the Mississippi River Valley. For the rest of the period, the upper
low/trof will gradually push farther south and east and into our
area. The trof axis is expected to move over the Carolinas over the
weekend as the upper low opens back up to the mean flow. By the
end of the period early next week, the upper trof will have moved
offshore with heights recovering in its wake. At the sfc, a very
broad, stacked low will be centered over the Great Lakes region
as the period begins. Anomalously cold thicknesses will set up
over our area as we enter a WLY to NWLY flow regime. With plenty
of moisture available, at least sct upslope showers will likely
develop over the usual areas and expand further east during the
day Friday. Persistent WLY to NWLY flow will allow for ongoing
showers thru at least Saturday, and perhaps thru Saturday night.
With 850mb temperatures dropping with the cold thicknesses, expect
elevations above roughly 3500 ft to receive some snow mixed in
with the rain as precip develops, especially early Saturday.
Dry high pressure will build back in on Sunday as thicknesses
begin to recover behind the departing upper trof. Temperatures
will be 5-10+ degrees below normal Friday and Saturday and begin
to recover on Sunday.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
At KCLT and elsewhere: VFR conditions are expected through the
morning hours on Tuesday at all terminals, with only thick patches
of cirrus to contend with until a dynamic weather system arrives
Tuesday afternoon. Wind should be light and southerly overnight and
early Tuesday. Conditions go downhill quickly Tuesday afternoon
from southwest to northeast as a strong upper wave brings deep
moisture. Low clouds and widespread showers will cross the region
with the first wave during the bulk of the afternoon, with each
terminal most likely experiencing a 4-6 hour period of steady rain
with embedded heavier showers/thunderstorms. To cope with this,
all terminals will feature a prevailing MVFR condition with a
temporary IFR to handle the heavier rain potential. In reality,
this could easily turn out to be IFR/LIFR at some terminals. The
heavier precip will depart right around the end of the fcst period
at most locations, but with KCLT having the longer fcst period,
we include a lingering IFR ceiling Tuesday evening. A period of
low level wind shear is also possible in the wake of the main
precip area, so that is featured at KCLT but omitted at the other
terminals whose fcst ends at 00Z.
Outlook: Restrictions will linger Tuesday night behind the first
system. Partial clearing takes place Wednesday morning with a
possible return to VFR, before a cold front brings another round
of precip Wednesday evening or Wednesday night. Gusty westerly to
southwesterly winds expected behind the front Thursday thru Friday.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...JPT
NEAR TERM...CAC/PM
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...PM
Area Forecast Discussion
National Weather Service Huntsville AL
904 PM CDT Mon Apr 4 2022
.NEAR TERM...(Tonight)
Issued at 903 PM CDT Mon Apr 4 2022
High clouds were increasing from west to east, but remained thin
enough to allow for quicker radiational cooling in our eastern
counties. Temperatures have dipped quickly into the middle to upper
50s in these areas, but area holding in the lower to middle 60s west.
An MCS was taking shape as expected over north TX into southeast OK.
The latest HRRR continues to suggest showers and perhaps embedded
thunderstorms on the northern extent of the MCS arriving just before
12Z in northwest AL. The NAM is a bit slower than this, arriving
after 12Z. The system will encounter very dry low to mid levels
initially noted on the BMX sounding which may be a factor in the
timing of arrival. But for now, best course is to keep the forecast
about as is.
.SHORT TERM...(Tuesday through Wednesday Night)
Issued at 240 PM CDT Mon Apr 4 2022
The system we are watching for tomorrow is right now
producing supercells over central Oklahoma, and will ride along a
boundary currently located south of us between Montgomery and
Birmingham. As we will be cooler and significantly more stable than
areas farther south, the chance for even thunderstorms along the
north side of the line that moves through our area will be pretty
low. Much less anything strong to severe. What SPC is looking at when
deciding to keep us in the Marginal risk is the potential for
destabilization above the stable boundary layer behind the main line
Tuesday afternoon. A few of the CAMs and even global models suggest
the potential for a few scattered to isolated thunderstorms just
ahead of the surface low that moves across our area Tuesday
afternoon. Model soundings do suggest we may destabilize enough for a
stronger storm or to to possibly develop. Primary threat would be
strong winds and maybe some small hail.
Once the storm chances end Tuesday evening we look ahead to
Wednesday. This will be our better chance for severe weather as the
warm front will have lifted well to our north Tuesday
afternoon/evening. With lows in the mid-to-upper 50s Wednesday
morning, we`ll warm right up into the mid-to-upper 70s Wednesday
afternoon, with ample destabilization ahead of the cold front that
will approach from the northwest. The best environment for stronger
storms will be along and east of I-65 where there will be more time
for the environment to energize before the front arrives and CAPE
Values get up into the 1000-1500 J/kg range. Thunderstorms will be
possible across our entire area, though, as we expect a QLCS to
develop to our northwest and move across our area Wednesday afternoon
and evening. With ample shear and instability, all modes of severe
weather will be possible including tornadoes, hail, damaging winds,
and locally heavy rainfall. This system should exit our area to the
east close to 12 AM Thursday.
.LONG TERM...(Thursday through Sunday)
Issued at 240 PM CDT Mon Apr 4 2022
The system that brought us active weather in the short
term will churn over the Great Lakes Region for a little while
longer, but the cold front will be out of the forecast area as we
start the latter half of the work week.
High pressure originating from Canada will start to build in on the
backside of the upper level low that`s anchored over the Great Lakes
region on Thursday. CAA from breezy NW flow on Thursday will start
the cooling trend making daytime high +10 degrees cooler than Wed
afternoon with temps in the low/mid 60s. Dry conditions will prevail
through the day under mostly sunny skies and lows will only be a tad
cooler, with temps reaching the upper 30s/lower 40s.
We will really feel those cooler temps Friday and Saturday. High
pressure builds in further and the tight pressure gradient will keep
winds breezy on Friday. A lobe of energy from the stalled low up
north will brush the northern half of the CWA and provide an increase
in cloud cover and possibly a few showers Friday afternoon into
early evening. Saturday will be much like Friday with highs in the
lower 50s, but with less cloud cover. Overnight lows both nights will
be in the mid 30s, so be sure to protect sensitive or early
vegetation from frost that may develop. Not confident in precip
occurring early Saturday morning, however if any light precip brushes
southern middle TN, a few snowflakes could mix in up in the higher
elevations. The stubborn upper level low will finally weaken and lift
as the amplified ridge pushes eastward Sunday and the ridge axis
slides through. This will bring lighter winds, mostly sunny skies and
warmer temps with highs reaching the 60s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 541 PM CDT Mon Apr 4 2022
VFR to start the TAF period with some passing high clouds and light
winds. A system to our west will move through northern Alabama early
tomorrow morning. This will increase winds and showers will
overspread the terminals around or shortly after sunrise. Confidence
in thunderstorms is low so left mention in a PROB 30 group. Rain
should come to an end from west to east late morning to around
lunchtime. However, low clouds may stick around until the end of the
TAF period.
&&
.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&
$$
NEAR TERM...17
SHORT TERM...McCoy
LONG TERM...JMS
AVIATION...GH
For more information please visit our website
at weather.gov/huntsville.
Area Forecast Discussion
National Weather Service Wilmington NC
742 PM EDT Mon Apr 4 2022
.SYNOPSIS...
Dry high pressure will slip offshore tonight. Unsettled weather
is expected Tuesday and again Thursday with the possibility of
strong to severe thunderstorms. Temperatures will increase mid
week, followed by a cool down late Thursday into this weekend.
&&
.UPDATE...
No significant edits required. Variable cirrus overnight, at
times mostly clear. This may lead to pockets of mist inland
aft 9z/5am where lighter winds are anticipated. Dewpoints to
continue a gradual ascent overnight throughout the region ahead
of potent disturbance that brings severe weather risk Tuesday.
&&
.NEAR TERM /THROUGH TUESDAY/...
High pressure in the process of passing to our northeast. This will
lead to moisture return tonight but any fog that develops will not
lead to significant visibility restrictions, see aviation section. A
surface warm front moves ashore around daybreak Tuesday, and the WRF
has some odd-looking QPF as it does so (the HRRR has a few showers
but they seemingly more plausibly stay offshore). Tuesday a very
transitional and increasingly active day. After a nice start with
sunshine (perhaps slightly dimmed by a few high clouds) several
forcing mechanisms for ascent kick in. Warm advection in the low
levels will start to benefit from deeper ascent from PVA in the mid
levels, with height falls not far behind. Low level wind fields will
strengthen as well, with many of these factors ramping up at about
21Z. Shower approaching from the west will increase in coverage and
intensity. The severe weather threat will also increase, while also
becoming very north-south graded, highest south. Shear increases
substantially area-wide but most of the precip will arrive
well after the diurnal insolation maximum and so the generation of
instability is in question, less due to our sunny start but more on
account of a subsidence inversion that mixes out 21-00Z leaving us
will paltry lapse rates aloft. There should be a wind damage and
tornado threat from even the shallower storms moving through for a
few hours surrounding 00Z after which low level hodographs
straighten considerably. Moderate to heavy rainshowers continue
thereafter.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
Short Term period will be quite active over the local area with
two chances for severe wx. First, with lingering convection
discussed in the Near Term section. Again, greatest threats are
damaging wind gusts and isolated tornadoes. Conditions then dry
out overnight as low pressure pushes off to the NE. Mainly dry
into Wednesday as a mid-level ridge traverses the area, with
the exception being far southern areas where better moisture
will reside and PoPs are in the 20-30% range. Next high chance
of rain arrives late Wednesday night into early Thursday with
ahead of a strong cold front. At least modest destabilization
is expected, and with deep-layer shear moderate, severe wx is
possible, with the main threat again damaging wind gusts. Temps
above normal through the period as well, with highs aoa 80 both
days inland.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Quiet and dry for the duration of the Long Term period with a
high-amplitude upr-level trough traversing the eastern CONUS.
Main item of note will be cooler temps, most noticeably the
overnight lows...ranging from the upr 30s to mid 40s over the
weekend.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
VFR. most of TAF cycle becoming MVFR in BKN015-BKN025 late in
TAF period ahead of line of showers and strong to severe TSTMs.
The severe weather potential transits area just beyond this TAF
period. By 16z Tuesday, S-SSE winds 11-16 kt, gusts to 25 kt
ahead of approaching system. Visibility over inland NE SC aft
22z may drop to 3nm in rain.
Extended Outlook...Tempo MVFR to IFR conditions Tuesday night
as low pressure brings showers and isolated thunderstorms. A
second system Wednesday night through Thursday will likely
bring additional flight category restrictions.
&&
.MARINE...
Through Tuesday: Veering continues as high pressure to our
north moves eastward with some rapidity. Southerly flow
established by morning as a warm front moves inland. This flow
regime to strengthen all of Tuesday as an area of low pressure
both surface and aloft approach, with seas following suit.
Tuesday Night Through Saturday: A SCA has been hoisted starting
early Tuesday evening, as southerly winds and seas ramp up with
the pressure gradient increasing ahead of approaching low
pressure. As the low passes to the N then NE, winds over the
local area will gradually shift to the SW, remaining at SCA
thresholds until early to mid morning Wednesday, with seas up to
6-7 ft. The SCA may need to be extended should these seas
last longer than currently expected. Some improvement then for
Wednesday, before another SCA is likely Thursday as a cold front
crosses the area. Seas may linger around 6 ft out 20nm
thereafter until early Saturday.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...Coastal Flood Advisory from 1 AM to 4 AM EDT Tuesday for
NCZ107.
MARINE...Small Craft Advisory from 6 PM Tuesday to 9 AM EDT Wednesday
for AMZ250-252-254-256.
&&
$$
UPDATE...Colby
NEAR TERM...Bacon
SHORT TERM...MAS
LONG TERM...MAS
AVIATION...8
MARINE...MAS/MBB
Area Forecast Discussion
National Weather Service Lincoln IL
743 PM CDT Mon Apr 4 2022
.SYNOPSIS...
Issued at 743 PM CDT Mon Apr 4 2022
Rain showers are expected to move northeast overnight, mainly
remaining confined to areas south of I-70 through sunrise. Expect
these showers to steadily advance across central Illinois on
Tuesday, though areas near I-74 should remain dry much of the
morning. Temperatures will be fairly typical for early April,
topping out around 60 degrees on Tuesday across central and
southeast Illinois.
&&
.UPDATE...
Issued at 743 PM CDT Mon Apr 4 2022
Lingering stratocumulus deck continues over northern Illinois this
evening, with the southern fringes near Peoria and Bloomington.
HRRR ceiling plot suggests this will stick around in those areas a
good part of the evening, while high clouds continue to fill in
over the remainder of the forecast area. The rain in southern
Missouri will gradually advance into southern Illinois overnight
and mainly remain confined to locations south of I-70 through
sunrise. Further north, east winds will result in a fairly dry air
mass that needs to be overcome, so rain chances on Tuesday morning
were adjusted to slow the arrival in the northern CWA.
&&
.SHORT TERM...(This evening through Tuesday)
ISSUED AT 305 PM CDT Mon Apr 4 2022
A cold front has reached from Champaign to Shelbyville on its way
into southern Illinois, as the parent low pressure progresses
across southern Lake Michigan and lower Michigan. Gusty W-NW winds
will continue behind the front for the rest of the afternoon, but
they should dissipate with the approach of sunset. A brief period
of surface high pressure will provide dry conditions for most of
the night. However, a southern stream low pressure system will
move from Oklahoma to eastern Tennessee on Tuesday, with a 500 mb
shortwave just to the NW of that SFC low. Those features will
trigger a wave or light rainfall advancing northward into our CWA
Tuesday morning. The coverage will be highest south of I-70, where
we kept a small area of Likely PoPs. Rain chances will be present
in our entire CWA on Tuesday, but mainly only slight chance for
areas north of Bloomington to Peoria.
&&
.LONG TERM...(Tuesday night through Monday)
ISSUED AT 305 PM CDT Mon Apr 4 2022
Tuesday night will feature our most active weather of the week,
as a warm front/cold front combo progress across Illinois. They
will be associated with an occluding low pressure system that will
progress from the Dakotas Tuesday night, to Wisconsin by Thursday
morning, then merge with an East Coast low Friday night. The end
result will be a line of showers and thunderstorms Tuesday night
across our CWA with the cold frontal passage. Instability will be
the limiting factor for thunderstorms, due to the cold FROPA
occurring at night. There appears to be sufficient bulk shear this
far north to still include thunderstorms in the forecast, but
severe weather is not expected in Illinois. Better chances will
remain farther south. Moisture transport ahead of this system will
not be significant, so rainfall amounts should remain less than an
inch in most of central IL.
In the wake of that system, a deep upper trough will dominate the
entire Upper Midwest and Great Lakes. There should be a break in
the rain for Wednesday afternoon and evening, before the occluded
low wraps additional moisture and lift into at least the northern
half of Illinois on Thursday into Friday. Cold air will arrive
with that secondary system, which could trigger some snow showers
later Thursday night and Friday morning. No snow accumulation is
expected. Any snow showers should transition back to rain later
Friday morning before precipitation ends early Friday afternoon.
Chilly air will settle into Illinois Friday night, as low temps
approach freezing in a large portion of central IL. Below normal
temps will continue on Saturday and Saturday night, before
noticeable warming returns on Sunday and Monday, when highs reach
the 60s both days.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 617 PM CDT Mon Apr 4 2022
Southern fringes of the MVFR cloud deck extend from KGBG-KPIA-KBMI
at 23Z, and should break up over the next couple hours. Main
aviation impacts will then spread from south to north Tuesday
morning, as low clouds and rain move into the area. Latest
guidance is leaning toward a 4-6 hour period when ceilings are
likely to be below 1,000 feet, with some improvement near
KSPI/KDEC late in the period as the rain pushes north.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SYNOPSIS...Geelhart
SHORT TERM...Shimon
LONG TERM...Shimon
AVIATION...Geelhart
Area Forecast Discussion
National Weather Service Lake Charles LA
1039 PM CDT Mon Apr 4 2022
.UPDATE...
Inherited grids are on track with current observations, therefore
no update was performed. Showers are lifting north through the
CWA in response to a warm front. Latest model runs of the HRRR
show showers and thunderstorms ramping up out ahead of an
approaching frontal boundary out to the west of us. That activity
is expected to begin early tomorrow morning with the higher severe
potential occurring as the tail of the boundary sweeps across the
northern part of our CWA from daybreak to mid morning.
Stigger/87
&&
.DISCUSSION...
&&
.PREV DISCUSSION... /issued 648 PM CDT Mon Apr 4 2022/
DISCUSSION...
For the 04/05/2022 0000 UTC TAF package.
AVIATION...
A period of messy weather will begin to unfold tonight as a warm
front lifts north across the region, followed by a cold front
tomorrow morning. At this time, a few showers are ongoing along
the coast near BPT/ARA. This convection will continue to lift
inland through the next few hours, with more showers and
potentially thunderstorms developing along the same boundary
affecting the I-10 terminals through the evening into the
overnight hours. Have included a few tempo groups to account for
this first round of storms, which includes the potential for
isolated thunderstorms. After midnight, convection should come to
somewhat of a lull before the next round of showers and
thunderstorms begins tomorrow morning as the cold front moves
through. This will bring the potential for more widespread
thunderstorms, some of which could be severe. This second round of
convection should largely taper off around the noon hour, however,
a few light showers may continue mainly across Acadiana into the
afternoon. By the end of the TAF period, conditions will be
improving area-wide, with a return to VFR CIGs likely by the end
of day tomorrow.
17
PREV DISCUSSION... /issued 434 PM CDT Mon Apr 4 2022/
SHORT TERM [Today through Wednesday]...
Clouds are currently moving into the area with temperatures in
the upper 70s to low 80s. Chances for showers and thunderstorms
will increase this afternoon into this evening.
Shortwave energy will be expected to move through the area later
this evening into the overnight hours. The Storm Prediction
Center has northern parts of our area in an Enhanced Risk of
severe weather, becoming a Slight Risk and then a Marginal Risk as
you progress further south towards the coast. The main concern
will be how far south the convective complex will progress when it
eventually reaches our area from the west this evening into the
overnight hours. Storms will be expected to move out of the area
by late tomorrow morning.
The HRRR is continuing to indicate a possible bow echo with the
system which suggests a possible damaging wind threat. Large hail,
a few tornadoes, and flooding will be possible as well.
A few showers and thunderstorms will be possible on Wednesday with
a cold front expected to pass by the end of the period.
55
LONG TERM [12Z Thursday Morning through 12Z Tuesday Morning]...
Thursday morning looking at a large vertically stacked low over the
Great Lakes region that extends from the Rockies to the US east
coast and south into the southern States. A series of sfc highs are
rotating around the back side of the low are will be driven down
along the eastern slopes of the rockies and into central Texas. The
elongated area of high pressure by Thursday afternoon will extend
from Canada south into the western Gulf of Mexico. The axis of the
upr lvl trof will be to the east which is going to give the region
sinking air aloft and clear skies as cold air advection draws to a
close.
Lows by Friday morning from radiational cooling will have AEX near
40... Lake Charles low 40s and BPT and LFT in the mid 40s. The upr
lvl low continues to drift into east and into the eastern Great
Lakes becoming a big elongated with the exiting 300 mb jet lifting
out into the mid-Atlantic states Saturday evening. Saturday
afternoon temperatures will be in the upper 70s. The upr lvl low
opens up while exiting the New England states and the surface highs
shifts over towards the Florida Panhandle on Sunday. Clouds finally
return late in the day on Sunday. By this time the nose of the
southern jet begins to move into the northwest gulf region Monday
afternoon with a chance for some showers during the afternoon hours.
The warming trend will continue into Tuesday morning.
K. Kuyper
MARINE...
Southeasterly winds currently being seen will be expected to
become elevated this evening into the overnight hours. Therefore,
a Small Craft Exercise Caution will be issued for this evening
into the overnight hours. Showers and thunderstorms will be
possible this afternoon into tomorrow morning. Some storms could
be severe.
55
LCH WATCHES/WARNINGS/ADVISORIES...
LA...None.
TX...None.
GM...Small Craft Exercise Caution through Tuesday morning for GMZ450-
452-455-470-472-475.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 65 84 67 83 / 90 60 0 20
LCH 66 81 66 83 / 70 50 0 0
LFT 67 84 68 85 / 70 80 0 10
BPT 67 85 66 85 / 50 30 0 0
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...None.
TX...None.
GM...Small Craft Exercise Caution until 10 AM CDT Tuesday for GMZ450-
452-455-470-472-475.
&&
$$
Area Forecast Discussion
National Weather Service Nashville TN
814 PM CDT Mon Apr 4 2022
.UPDATE...
FOR EVENING DISCUSSION.
&&
.DISCUSSION...
Radar this evening shows a few scattered showers continue across
our northern half. This activity will continue to diminish and
lift out of the area with time per latest HRRR model runs, so
will only show a slight chance or low chance pop across our north
the rest of the night. Weak warm front remains in place over our
northern counties as well at this hour, with temperatures in the
upper 50s along the KY border, but in the 60s and 70s to the
south. Thick cloud cover should keep low temps up somewhat
overnight, and current forecast lows may be on the high side but
most areas should still drop into the 50s. Late tonight, a MCS
currently developing near the DFW metroplex will race eastward
through LA/MS/AL, with a large area of stratiform rain and some
lightning spreading into Middle Tennessee near/after 12Z and
continuing into the afternoon before exiting stage right.
Inherited forecast has all this covered well so no changes were
made for tomorrow.
&&
.AVIATION...
00Z TAF DISCUSSION.
Very light showers showing up on radar at 00Z. These will continue
to skirt across CWA north of I-40 through 07Z. Will include VCSH
for CKV and CSV. Winds will be light and variable this evening
and overnight.
A low pressure system will move south of the area tomorrow
bringing showers and rain to the terminals. There could be a few
rumbles of thunder but expect them to be more over AL so did not
include in the TAF. Bring VCSH in by 12Z to 14Z. Rain will affect
VIS and CIG at times during the day with MVFR to IFR conditions
expected.
Winds will be out of the south tomorrow with gust 15+
kts...especially in and around the stronger showers.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION......Shamburger
AVIATION........12
Area Forecast Discussion
National Weather Service Pueblo CO
936 PM MDT Mon Apr 4 2022
.UPDATE...
Issued at 915 PM MDT Mon Apr 4 2022
...Expanded High Wind Warnings to include the northern Sangres De
Cristo and Wet Mountains, Wet Mountain Valley and Huerfano
county...
Based on 00z high res data, have expanded current suite of high
wind warnings to include all of the southeast mountains and
adjacent lower elevations including Huerfano county. Already
seeing some response in winds along the lee of the northern
Sangres and HRRR shows this increasing after 06z (midnight) with
potential for high wind mountain wave development through 12z (6
AM). Potential for high winds spreads into the adjacent lower
elevations in the 12z to 15z (6 AM to 9 AM) timeframe. Have
started High Wind Warnings around 3 to 6 hours earlier as well.
Model cross-sections show this event shifting from a mountain
wave overnight into the early morning hours to a more deep mixing
high wind event by Tuesday afternoon, with the Wet mountains and
adjacent I-25 corridor seeing the strongest winds in the late
morning and afternoon.
There are still some challenges to this forecast with the
potential for the Wet Mountains and Wet Mountain valley to come up
a little shy of high wind criteria. Portions of El Paso in the
lee of Pikes Peak and the Wets, where a distinct wind minima will
extend, may also avoid the higher gusts. But spotty high wind
criteria will still be possible in other locations of these
counties, so current suite of high wind warnings is basically
throwing a larger lasso around many of these potential localized
high wind areas. Gusts to 80 mph will be possible for the mountain
areas, with gusts 60 to 65 mph for the lower elevations.
Northern El Paso shows some drying in the dew points towards 00z
but its still not enough to get below 20% RH which is the lower
bound value for critical fire weather even with high wind
criteria. So will leave the Red Flag Warnings as is for now. As
more of the 00z suite of models arrives, this will continue to be
reassessed. -KT
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 338 PM MDT Mon Apr 4 2022
1) Strong winds over parts of the region tonight into tomorrow.
2) Fire weather concerns over parts of the region.
3. Some wind driven snow over the central mtns this evening into
tomorrow.
Currently...System which brought some impressive snow amounts to
parts of the region last night into this AM has moved east, and
skies were predominantly clear over the region at 2 pm. However...a
strong weather system which promises to bring LOTs of wind to the
region was pushing into NW CO per sat pix imagery. This system was
beginning to have an influence as south to southwesterly winds were
beginning to pick up across the plains, with temps across the plains
ranging from the mid 40s in N El Paso county to around 60 generally
south of the Arkansas River. Valleys were generally in the 40s in
the 50s. Temps aloft were still rather cold as mtn top temps were in
the teens.
This Afternoon Into Tonight...
Main concern is wind will begin to start to ramp up shortly over the
mtns as the system to our NW moves closer to the region. Winds of 15
to 30 mph by this afternoon will be in the 30 to 50 knt range by
midnight and will continue to increase during the predawn hours.
Strongest winds will affect the central mtns, the Pikes Peak region
and the eastern mtns tonight. with the overall strongest winds over
Pikes peak
Snow will start to ramp up Prior to midnight, with most of the snow
occurring over the central mtns. Snow amounts will not be all that
much, but the combo of winds and snow will make for difficult travel
conditions over the passes tonight in the central mtns.
Prior to sunrise, winds will work down the mtns, and the Upper and
Mid Ark River Valley along with the Wet Mtn valley will be impacted.
As for hilites, High Wind warnings go into affect for the Mid Ark
Rvr valley and Teller county/Pikes Peak around 3 AM.
Tomorrow...
High wind threat and Fire weather threat ramp up. A high wind
warning goes into affect at 7Am for the southern Sangres and last
until around noon. By mid morning, mixing will be underway and the
strong winds will start to push out onto the plains, with strong
winds expected to be ongoing by late morning and into the afternoon
time period. The strongest winds are expected to occur over eastern
Fremont, Pueblo and El Paso counties. with the overall strongest
winds across eastern Fremont and NW Pueblo counties. Strongest winds
in EL Paso county will be over northern El Paso county.
As for Colorado Springs, winds will be quite squirrelly this region as
Pikes Peak will be blocking the strong winds flow,
As for Fire Weather, A RED FLAG warning has been issued for the
lower elevations of Las Animas and Baca counties and for southern EL
Paso county. Although it is going to be winds across ALL of the
plains tomorrow, areas along the Arkansas river received quite a bit
of wetting rain, and this area will likely be too moist for fire
spread. However, areas along the NM/OK border did not receive any
significant rain and this area is receptive for fire spread.
For El Paso county, quite a few areas relived rain, but it was very
light, generally less than 0.05 per CoCoRahs reports, and it will be
windy withe relatively low RH values. As for northern El Paso
county, this area was NOT included in the Red Flag warning area as
RH values will likely be too high (>20 percent).
The San Luis valley and SW mtns will also be quite windy tomorrow,
but winds should remain below high wind criteria.
.LONG TERM...(Tuesday night through Monday)
Issued at 338 PM MDT Mon Apr 4 2022
Key messages:
1) Tuesday evening through early Wednesday morning, snow will be
possible over the northern Continental Divide and Rampart Range,
which will be coming to an end. Some rain/snow showers could occur
over the upper Arkansas River Valley.
2) Spotty critical fire weather conditions will be a concern over
the southern plains for early Tuesday evening for southern El Paso
County, but due to recent rainfall, should not be of much concern
for the southern plains with the exception of Baca County.
3) More widespread critical fire conditions will be likely over the
plains and San Luis Valley for Wednesday during the afternoon and
early evening. Widespread fire weather conditions will be possible
Thursday afternoon/early evening over the plains and San Luis Valley
again. Northerly winds will still be strong and gusty over most of
the CWA on Thursday.
4) Northerly winds will continue to be strong and gusty over the
plains on Friday. Winds will increase out of the southwest over the
CWA for Saturday. Some spotty areas of fire weather concerns will be
possible over the southeastern plains and along the I-25 corridor
for Friday and Saturday afternoon/evening.
5) A potentially high impact low pressure system will result in very
critical fire weather conditions over the plains and San Luis Valley
on Sunday afternoon and into Monday of early next week. Snow will
begin over the Central Mountains and then spread out over the
eastern mountains by later in the evening on Sunday and throughout
the day on Monday with rain showers over the lower elevations.
Thunder could also be possible.
Detailed discussion:
Tuesday night through Wednesday...
The shortwave trough will continue to exit the region with only a
few lingering snow showers expected over the northern Continental
Divide and Rampart Range. High pressure will subsequently build in
to the west and the tightening of the pressure gradient will
increase northerly winds. Combination of this will low relative
humidity values will result in widespread critical fire weather
conditions for Wednesday afternoon and early evening over the most
of the plains and the San Luis Valley. Winds have been a little
under for the NBM and therefore a blend of the 90th percentile was
utilized once again as they were yesterday to enhance these.
Dewpoints for Wednesday afternoon and early evening have also been
slightly adjusted down as well as they have been for the past few
days, using a NBM 10th percentile blend. It will also be very windy
over the higher terrain and with the recent snowfall, there could be
areas of blowing snow across the higher peaks.
Temperatures will still be relatively cool with the northerly wind
flow, even with mixing due to the gusty winds. On Tuesday night,
lows will drop to the upper 20s and lower 30s over the plains, and
then generally in the teens and 20s in high country, with single
digits for the highest peaks. On Wednesday, high temperatures will
only get up into the 50s for the plains and San Luis Valley, and
anywhere from the 40s for high mountain valleys, to the 20s and
teens for the highest peaks.
Thursday through Saturday...
An upper level jet over Colorado coupled by the deepening low
pressure system downstream over the Great Lakes, and a ridge over
the western CONUS further amplifying with a strengthening high
pressure, will enhance the northerly wind flow over the CWA, and
especially over the plains for Thursday and into Friday until it
transitions far enough to the east to not have a significant
influence and the pressure gradient weakens.
On Thursday and Friday, the strong and gusty northerly winds will
continue to be an issue, more so for the entire CWA on Thursday and
just the plains on Friday. Critical fire weather concerns will
likely be in place during the afternoon and early evening for most
of the plains and the San Luis Valley. On Friday, the area of
concern becomes more confined to the southeast plains, although some
spotty fire weather conditions could exist over portions of the I-25
corridor. Northerly flow will still keep the southeast Colorado
relatively cool, with highs still only topping out in the upper 50s
for most locations on the plains. With the air mass becoming more
modified by Friday, high temperatures will be back around the
seasonal average for this time of year.
For Saturday, deterministic models have been becoming more
consistent with showing a longwave trough deepening over the
northwest CONUS, and this will begin to influence the winds as they
increase out of the southwest over most of the CWA. The increasing
downsloping winds will cause some spotty areas of critical fire
weather conditions over some areas of the plains, and it will also
allow for very warm temperatures across the plains, with low 80s
likely in the lower Arkansas River Valley.
Sunday through Monday...
Deterministic models and ensemble members have continues to become
more finely tuned in agreement with a major shortwave trough with a
slightly negatively-tilted axis, that is associated with the
deepening longwave trough over the northwest CONUS, which will
continue to propagate towards the region. This major shortwave had
the potential to be a high impact weather event, although it is
still too far out in the forecast period to have any high confidence
that this will come to fruition. Currently, ECMWF model trends have
kept the surface low pressure center with this system to eject out
over the plains a little further to the north than what the GFS and
Canadian models are displaying. Ensemble members has also been
indicating that this will be drier over most areas of the plains,
which suggests the the low will remain further to the north due to
the projected path bringing it in from the southwest. If this ends
up happening, given the strength of the 700 mb wind flow ahead of
this trough over the southeast plains at over 60kts, there could
potentially be very high winds that will result in a possibly dire
situation with fire weather conditions over this region and much of
the plains. Temperatures with the ensembles do show quite a bit of
variance, which could allude to the possibility that there could be
some change in the location of the low pressure system, and this
could also change the impacts of how critical fire weather
conditions could be over certain areas. However, given the latest
trends, it is appearing to be more likely that fire weather
conditions will be very concerning for Sunday, and possibly Monday
as well. These trends will need to be further analyzed in the
upcoming days as we get closer to the weekend. Along with the winds,
this system looks to bring heavy amounts of snow to the mountains
and even the possibility of thunderstorms. -Stewey
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 534 PM MDT Mon Apr 4 2022
Breezy south winds this evening will decrease but become
intermittently windy from the west at KPUB after midnight. There
is the potential for low level wind shear at both KPUB and KCOS
late tonight through tomorrow morning as strong west northwest
winds aloft spread down into the lower levels of the atmosphere.
This is trickiest at KCOS where wake flow downwind of Pikes Peak
could keep this wind shear layer right at the top end of the WS
depth. Once the NW winds kick in, gusts to 40 to 50 kts will be
possible at both KCOS and KPUB through the afternoon.
KALS will see enhanced southerly winds this evening become light
overnight but increase from the West Northwest with gusts to 40 to
45 kts tomorrow afternoon.
BLDU is possible though with recent precipitation, it is expected
that visibility restrictions will not be as likely unless the
ground dries more quickly than anticipated. Have kept BLDU out of
the TAFs for all three sites for now. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Wednesday morning through Wednesday
evening for COZ224-227>237.
Red Flag Warning from 11 AM to 7 PM MDT Tuesday for COZ227-230-
233-237.
High Wind Warning from 6 AM to 6 PM MDT Tuesday for COZ079-080.
High Wind Warning from 3 AM to 6 PM MDT Tuesday for COZ072>075-
077-078.
Winter Weather Advisory until midnight MDT Tuesday night for
COZ058-060.
High Wind Warning until 6 PM MDT Tuesday for COZ076-081-082.
High Wind Warning from 9 AM to 6 PM MDT Tuesday for COZ062-
083>087.
&&
$$
UPDATE...KT
SHORT TERM...HODANISH
LONG TERM...STEWARD
AVIATION...KT
Area Forecast Discussion
National Weather Service Tallahassee FL
858 PM EDT Mon Apr 4 2022
...SIGNIFICANT SEVERE WEATHER EVENT EXPECTED FROM LATE TUESDAY
MORNING INTO THE EARLY EVENING...
.UPDATE...
Quiet night in store. Current forecast is on track, so no changes
to the forecast.
There is currently quite a moisture gradient not far too our
south. Late this afternoon, the dewpoints in TLH was in the upper
40s, while it was near 70 down in St. Petersburg. 00z soundings
highlighted PW value of 1.19" at TBW, and only 0.42" at JAX. As
southerly flow picks up late tonight and Tuesday morning, this
sidelined moisture and more unstable air will come surging north.
We continue to watch CAMS guidance trickle in relating to
Tuesday`s severe weather event. The hourly-updating HRRR continues
to be bullish in bringing a large bowing segment toward southeast
Alabama around mid-day, with further progression into the FL
Panhandle and southern Georgia beyond that. The NAM shows quite a
bit of mid-level dry air to entrain to aid with cold-pool
development in the eventual MCS. This will help to push the squall
line along quickly and contribute to the potential for
significant severe winds in places. With this event, it is not so
much a matter of if severe weather parameters will come together,
but rather where they will come together.
&&
.AVIATION...
[Through 00Z Wednesday]
Quiet night with clear skies. S-SW flow will increase late tonight
and bring cigs, possibly below 1,000 feet, into ECP and DHN. The
big news will be a squall line of intense thunderstorms with
possibly damaging winds that will move across the terminals on
Tuesday. Arrival at DHN mid-day, with afternoon arrivals at ECP,
TLH, and ABY. Could hold off to late afternoon or early evening at
VLD.
&&
.PREV DISCUSSION [328 PM EDT]...
.NEAR TERM [Through Tuesday]...
Bottom Line: Severe thunderstorms, some possibly significant, are
expected to move through the forecast area on Tuesday. Destructive
winds of 70 mph, tornadoes (some strong), and locally heavy rainfall
are possible.
Details:
A shortwave trough will move across the Gulf Coast on Tuesday, ahead
of a larger longwave trough that will be over the Plains. At the
surface, a boundary over the central Gulf of Mexico will lift
northward tonight as a warm front and move inland early Tuesday
morning. While there could be isolated thunderstorms with this
front, the chances for severe weather appear low as most of the
showers and storms that do develop will likely be elevated north of
the warm front. Otherwise, tonight will be quiet with lows in the
mid-50s north to mid-60s near the coast.
Daytime Tuesday is the main meat of the event. An MCS will likely be
ongoing in southern Mississippi and Alabama, moving eastward into
our area during the late morning and early afternoon hours.
Thunderstorms will move into southwest GA and the FL Big Bend in the
afternoon. With this complex moving into our area during the day,
there is more instability to work with as CAPE increases to 1000-
1500 J/kg. Additionally, the LLJ will also increase to about 45-55
knots across the CWA. Deep layer shear will be near 40 knots with
low-level shear near 30 knots. SRH in the 0-1km layer will be near
150-250 m2/s2 range, and STP increases to 1-3.
With such strong winds just off the surface and plenty of
instability, destructive winds of 70 mph are possible, especially in
any bowing segments. The shear results in longer, curving
hodographs, which suggests an elevated tornado risk as well, some of
which could be strong given the strong wind fields. The greatest
tornado risk right now appears to be across southeast Alabama and
southwest Georgia. SPC has outlined areas from DeFuniak Springs to
Nashville northward in an Enhanced Risk of severe weather (level 3
of 5) with most elsewhere (outside of the southeast Big Bend) in a
Slight Risk (level 2 of 5). Everyone should review their severe
weather safety plans, have multiple ways to receive warnings, and
know where their safe place is, whether at work or at home.
Outside of thunderstorms, winds will be quite gusty with frequent
gusts up to 30 mph at times. Highs will be near 80. Dangerous rip
currents will continue at all beaches.
.SHORT TERM [Tuesday Night Through Wednesday Night]...
With Tuesday`s severe threat likely out of the area by Tuesday
night, a brief reprieve can be expected as much of the atmosphere
over the region will have been worked over by the prior MCS that
is expected on Tuesday. Wednesday will prove to be less cut and
dry compared to Tuesday as an mid to upper level vorticity
streamer left behind from Tuesday`s shortwave is expected to
linger across the region in a west/east orientated ribbon. This
will act as an initiation source for thunderstorms on Wednesday.
With a surface high pressure system parked east of Florida over
Bermuda, southwesterly flow will be present across the region on
Wednesday. This will allow for the advection of warm moist air
from the Gulf over the region. This will allow for instability to
reload rather quickly Wednesday once the sun rises.
With the lack of any strong upper level shortwave or trough in
close proximity to the area, low level shear will be less
prevalent on Wednesday across the region as only 15 knots will be
present. Deep layer shear is expected to be near 50 knots through
the 0-6 km layer. This will allow for some supercell development.
The biggest difference on Wednesday, will be the presence of very
steep lapse rates. An Elevated Mixed Layer is expected to move
over the region from the Mexican Plateau with near 7.5 C/Km lapse
rates over the entire area Wednesday. With these steep of lapse
rates coupled with moderate to strong deep layer shear mentioned
above, there will be the possibility of tilted supercells on
Wednesday that will be able to produce large hail, damaging winds,
and possibly a brief tornado (although that threat doesn`t appear
to be as great given the lack of low level shear). Nevertheless, a
slight risk (2 of 5) has been issued for the entire forecast area
on Wednesday with the threat appearing to be areawide. Depending
on how much rainfall falls Tuesday, there could possibly be a
flood threat on Wednesday as well if training of storms develops.
.LONG TERM [Thursday Through Monday]...
An unusually strong upper level trough and cold front is expected
to clear the severe weather out of the region by Thursday
afternoon. This upper level trough will create windy conditions
across the region for several days as it slowly progresses
eastward. With relatively strong and consistent northwest flow and
subsequent cold air advection over the region, expect below normal
temperatures for both Friday and Saturday, with highs only
climbing into the upper 60s to low 70s across the area. Low
temperatures will follow suit, with lows Friday night through
Sunday night dipping into the low to mid 40s for much of the area.
portions of SE Alabama and Georgia counties north of Albany could
see temperatures drop into the upper 30s briefly Saturday night.
No frost or freeze is expected at this time; however, this should
be monitored in the coming days as the model guidance becomes more
clear on the airmass that is moving into the area. Overall, the
remainder of the long term will be calm with surface high pressure
settling into the region through the early work week, with a
resurgence of warmer temperatures expected by Monday.
.MARINE...
Southerly to southeaster winds will gradually increase overnight
tonight and tomorrow ahead of a strong MCS that is expected to
move through the region tomorrow afternoon. This will lead to
Advisory level winds and seas across the western leg of marine
zones, and cautionary conditions for the three eastern legs of
marine zones in the area. A brief reprieve of small craft
conditions is expected for the middle of the week from Wednesday
and Thursday; however, they will remain elevated at cautionary
levels during this time frame. With another strong upper level
trough and subsequent cold front moving through the region on
Thursday evening, expect advisory level winds and seas to return
overnight Thursday. Expect showers and thunderstorms on Tuesday
and Wednesday, but expect the area to clear out behind the cold
front that pushes through Thursday.
.FIRE WEATHER...
A line of strong to severe storms will move through the area on
Tuesday, bringing the potential for damaging wind gusts and isolated
tornadoes. Transport winds will increase out of the south to
southeast at 30-35 mph, which will lead to high dispersions. On
Wednesday, the coverage and intensity of storms is a bit uncertain,
but large hail and damaging winds will be possible again. Outside of
storms, good dispersions are expected. A cold front clears the
forecast area during the day on Thursday. Dispersions will be high
away from the coast due to elevated transport winds and high mixing
heights.
.HYDROLOGY...
With multiple rounds of severe weather expected on Tuesday and
Wednesday, there could be the possibility for localized flash;
however, confidence in locations is not high enough to warrant a
flash flood watch at this time. With a general 1-3 inches expected
and locally higher totals of 4-6 possible, flash flooding is
certainly not out of the question, especially where training of
storms can develop. Rises on area rivers is expected, and with
many currently in Action stage, some minor riverine flooding will
be possible for these basins that exceed more than 4 inches of
rain over a widespread area. This is particularly true for the
Ochlockonee and Withlacoochee River basins that have seen heavy
rainfalls over the past several events.
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur (while following all local, state, and CDC guidelines) by
calling the office or tweeting us @NWSTallahassee.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 60 80 67 82 65 / 10 80 80 70 70
Panama City 65 77 68 78 64 / 20 80 70 70 60
Dothan 57 77 66 83 60 / 20 90 60 60 60
Albany 57 79 67 84 63 / 10 90 80 60 60
Valdosta 60 82 66 81 65 / 10 70 70 60 60
Cross City 63 82 67 81 66 / 0 50 60 60 70
Apalachicola 65 77 68 77 66 / 10 70 70 70 70
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through late Friday night for Coastal Bay-
Coastal Franklin-Coastal Gulf-South Walton.
GA...None.
AL...None.
GM...Small Craft Advisory from 7 AM Tuesday to 1 AM CDT Wednesday for
Coastal waters from Mexico Beach to Okaloosa Walton County
Line FL out 20 NM-Waters from Mexico Beach to Okaloosa
Walton County Line FL from 20 to 60 NM.
&&
$$
UPDATE...Haner
NEAR TERM...Young
SHORT TERM...Bunker
LONG TERM...Bunker
AVIATION...Haner
MARINE...Bunker
FIRE WEATHER...Young
HYDROLOGY...Bunker