Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/13/22
Area Forecast Discussion
National Weather Service Birmingham AL
739 PM CDT Wed Oct 12 2022
...New SHORT TERM, AVIATION...
.SHORT TERM...
(Tonight through Thursday)
Issued at 649 PM CDT WED OCT 12 2022
The first wave has finally pushed east and south of Troy to
Eufaula early this evening. This area of storms did produce some
hail, damaging winds and an instance of flooding. The latest model
guidance is in somewhat of an agreement that the area of storms
moving into Marion County will hold together and potentially make
it to near Heflin by midnight. Then the pre-frontal activity will
sweep in right behind that. It still appears that the lift and
instability will wane and the area of storms will eventually loses
coverage as it moves south of I-20.
Currently, 0-6km Bulk Shear values are at 40-50kt with low level
SRH values around 200. But the surface air has a CIN of 200 and
SBCAPE of 500 or less. These surface conditions will not improve
in the next few hours. 500 mb temperatures are cool and in the -12
C range as the upper trough approaches. Elevated instability and
forecast soundings indicate enough lift present along with some
drier air and veering of winds to have the potential of severe
storms. It appears the threat may be more of a hail and wind
threat. Will adjust the HWO to mention this severe threat until 3
am for roughly the northern two thirds of Central Alabama. It will
be advertised as Marginal. Otherwise, mentioned some patchy fog
and adjusted the temp trend slightly. Lows still expected in the
50s and 60s.
75
Previous short-term discussion:
(This evening through Thursday)
Issued at 1251 PM CDT WED OCT 12 2022
A very busy weather day is upon Central Alabama, a stark contrast
compared to what we`ve experienced over the last 30 days or so.
Not only have we had very beneficial rainfall across much of the
area, we`ve also had strong to severe storms across our southern
counties. These storms were more robust than were originally
forecast thanks to observed sounding parameters that came in
more unstable than model guidance was forecasting, and even
stronger than RAP analysis. The KBMX 12z sounding this morning
presented very unstable conditions aloft with steep lapse rates
above 700mb. Plenty of CAPE available within the hail growth zone
and almost 50 knots of shear just above 500mb from the southwest
contributed to a few storms with large hail measured around 2
inches. Strong storms are expected to continue as they become more
surface rooted and form a cold pool as they approach the U.S.
80/I-85 corridor this afternoon. Gusty winds and some hail are
possible with these storms, and an isolated severe wind gust can`t
be ruled out. With the clouds and rain ongoing across the area,
I`ve significantly reduced daytime high temps down into the lower
70s with mid to upper 70s on the periphery of the precipitation
shield.
As the first wave of showers and storms moves southeastward into
the afternoon hours, we`ll await the second round of showers and
storms. The second round of storms will develop out ahead of the
approaching cold front that is located all the way back in
northwest Arkansas. Storms that are currently developing along an
old outflow boundary moving into western Tennessee will continue
moving southeastward and may affect northwest counties early this
evening. We`ll watch these storms for severe potential, as our
western and northwest counties have seen the most sunshine and
diurnal heating today. We could see enough MLCAPE and plenty of
0-6km shear for damaging wind potential. As storms work their way
southeastward through the evening and overnight, they should
decrease in strength, as the airmass over much of Central Alabama
has been heavily worked over by all the showers and storms through
the day today.
The cold front should finally move toward the I-85 corridor by
Thursday morning with drier air slowly filtering in from the
northwest. We`re now seeing some indications from model guidance
that fog formation may be likely as the precipitation comes to an
end, mainly along and south of the I-59 corridor. We may need to
look at adding one mile or less fog into the HWO if these trends
continue. Skies should clear from northwest to southeast by
Thursday afternoon as temps rise into the low to mid 70s north
and lower 80s south.
56/GDG
&&
.LONG TERM...
(Thursday night through next Tuesday)
Issued at 212 PM CDT WED OCT 12 2022
A cool continental air mass will move into Central Alabama
Thursday night and into the day on Friday. Very pleasant daytime
highs can be expected with low humidity and dewpoints in the 40s.
We`ll moderate a bit as we go into the weekend as the surface
ridge becomes centered just off to our east and low level flow
becomes southerly. Long-range guidance is starting to come into a
little better agreement with the next cold front that approaches
the region Sunday and into Monday of next week. PoPs remain in the
chance to slight chance category as showers and potentially a few
storms could move through the area during the day on Monday.
Regardless of the rain chances, long range trends are certainly
colder. We could be looking at the first frost of the season for
some folks across the northern half of Central Alabama by
Wednesday morning.
56/GDG
&&
.AVIATION...
(00Z TAFS)
Issued at 649 PM CDT WED OCT 12 2022
Low ceilings will develop by 06z at all locations. Some of these
ceilings will drop to LIFR. Scattered thunderstorms are possible
the next several hours over Central Alabama. But by 03-06z, a
pre-frontal trough will move into the area bringing showers and
thunderstorms to all the northern sites. Expect a few hour delay,
then the southern sites. The northern sites begin clearing as
early as 15z with northwest winds 10-20kts expect behind the
front. The southern sites should lose the ceilings be 18z. The
last thing will be some patchy fog. Before any storms, there will
be a chance of some fog, possibly dense. Will monitor this
potential closely the next few hours.
75
&&
.FIRE WEATHER...
Showers and a few storms will continue to move through Central
Alabama tonight as a cold front approaches and moves through the
area. With increasing low level moisture, ceiling heights could
be below 1kft at times. Low level winds will be from the south
today, at 6-8mph, becoming northwesterly Thursday morning.
Rainfall should quickly end from northwest to southeast by early
Thursday with drier, post- frontal air starting to move into
northwest Alabama by afternoon, resulting in a period of RH values
in the lower to middle 30s across near and northwest of I-59
Thursday afternoon. 20ft winds increase to 6-10mph. 20ft winds
become southwesterly by Friday and decrease, as minimum RH values
fall below 30 percent.
&&
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 60 77 43 76 / 80 10 0 0
Anniston 62 77 46 76 / 70 10 0 0
Birmingham 63 76 48 76 / 80 10 0 0
Tuscaloosa 64 78 48 78 / 80 10 0 0
Calera 64 78 49 78 / 70 10 0 0
Auburn 64 78 50 77 / 50 10 0 0
Montgomery 67 81 50 80 / 50 10 0 0
Troy 67 81 50 78 / 50 20 0 0
&&
.BMX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...75
LONG TERM....56/GDG
AVIATION...75
Area Forecast Discussion
National Weather Service Columbia SC
1042 PM EDT Wed Oct 12 2022
.SYNOPSIS...
Scattered showers will continue tonight ahead of the front
which will cross the forecast area on Thursday afternoon. A
cool, dry air mass will settle over the region into the weekend.
Another cold front with limited moisture will move through the
Southeastern US early next week with additional cold air.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Widespread showers and an isolated rumble continue across the
central and eastern Midlands and CSRA with a few additional
showers over the Upstate. Over the next several hours expect the
showers to continue moving eastward with a few scattered showers
overnight. IR satellite imagery shows cloud tops continuing to
warm with coldest cloud tops south of the forecast area so
potential for thunder is low but can not be ruled out. With the
extensive cloud cover and southeast to southerly winds between 5
and 10 mph overnight lows will be in the low to mid 60s at most
locations.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
A cold front will push through the forecast area Thursday
although the deep moisture will have already shifted east of
the area. Expect some lingering showers through midday along and
ahead of the front. It will be warm before the front passes
with highs in the upper 70s to mid 80s. Dewpoint temperatures
will cool quickly as the front moves through the area in the
afternoon. The drier air will also put the brakes on any
lingering convective activity despite weak to moderate sbCAPE
values. It will be breezy ahead of and following the front with
gusts to around 20 mph. High pressure will build into the area
Thursday night under mostly clear skies with cold advection
supporting temperatures in the 50s. Winds may stay up on area
lakes due to the warm waters but it appears gusts should remain
under 25 kts and under Lake Wind Advisory Criteria.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Dry, high pressure will move into the Southeast Friday and
settle into the region. It will be cool on Friday night with
lows mainly in the mid 40s due to mostly clear skies and high
pressure overhead.
Additional shortwave energy will dig through the axis of the broad
upper trough over the eastern US. This will push a weak cold front
into the Mid-Atlantic late this weekend and into early next week.
PWAT values ahead of the front return to near normal but deep
moisture appears limited. This supports a slight chance of showers
on Sunday night. Cooler than normal weather is is expected by mid
week after the cold front eventually pushes through the forecast
area.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
High atmospheric moisture, along with some upper level energy,
expected to result in rain and showers in the near term.
Latest radar loops and high res models suggest good coverage
through about 05z-07z with a lull in the activity late tonight.
HRRR and SREF also indicating CIGS dropping to IFR to LIFR
later tonight through early Thursday morning, which makes sense
given rain cooling and S to SE winds.
Expect a slow improvement in CIGs Thursday ahead of a front that
will roll through in the afternoon. Appears there will be
minimal activity along the front. Latest hi res models suggest
the convective activity associated with the front, or prefrontal
boundary, will weaken as it approaches late tonight/early Thu
morning. Cant completely rule out isolated showers. Drier air
and a return to VFR expected behind the front, with increasing
west winds.
EXTENDED AVIATION OUTLOOK...No significant impacts to aviation
expected Thursday afternoon through Sunday.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
Area Forecast Discussion
National Weather Service Cleveland OH
937 PM EDT Wed Oct 12 2022
.SYNOPSIS...
A cold front moves east across the area tonight into Thursday
morning with a trough lingering over the the Lower Great Lakes
through Friday. A low pressure system moves across the Great
Lakes region on Saturday, followed by a second one on Monday.
&&
.NEAR TERM /THROUGH THURSDAY NIGHT/...
9:30 PM Update...
Widespread rain showers are observed on radar with embedded
isolated thunderstorms. Latest KCLE VWP continues to show
increasing shear/SRH, with 0-1km shear of 31 kts and 0-1km SRH
of 312 m^2/s^2, both of which are quite high. Mesoanalysis
suggests only MUCAPE of around 250 J/kg, however, this is
sufficient for sustained convection and embedded thunderstorms,
largely due to the strong forcing associated with the upper-
level trough. Strong gusty winds (mainly subsevere to 40 mph)
remains possible with the strongest convection, though the
chance for a quick spin-up is waning as instability decreases
and CIN increases. The 00Z HRRR suggests peak intensity now
through about 05Z, with some weak updraft helicity tracks
forecast through that time.
Previous Discussion...
A somewhat active near term period is anticipated as a cold
front advances towards the local area from the west. Despite
weak returns on radar, very little precip has reached the ground
due to dry air at the surface, but expect moisture to gradually
increase with the arrival of a low-level jet later this
afternoon into this evening. Expect shower cover to increase as
the front continues to move east, with precip reaching the
eastern fringes of the CWA by 03Z/11 PM EDT tonight. As stated
in previous discussions, there are still a couple of questions
left unanswered:
1. How much thunder will there be? Widespread cloud cover may
limit convection across most of the area, but latest satellite
is showing at least a little bit of clearing this afternoon.
Southern zones have the best shot at a few hours of clearing and
therefore destabilization. The best chance of thunder appears
to be south of US-30 and east of I-71.
and 2. How strong will any convection be? While CAPE will be
limited (under 500 J/kg), effective bulk shear values as high as
40 to 50 knots cannot be ignored - there may be a somewhat
organized line of showers/storms and a few storms may produce
localized gusty winds. The best instability should lie just to
the south of the CWA and any severe weather threat will depend
on how much convection develops.
Regardless, there`s a decent chance of showers with gusts to 45
mph and as with any high shear/low CAPE scenario, will need to
keep an eye out for brief spin-ups. The atmosphere should be
well- saturated with unseasonably high PWATs this evening, but
recent dry weather should minimize any flooding threat.
Although most of the frontal precip will exit to the east
Thursday morning, residual troughing along with cold air
advection/flow off of the lake will lead to scattered lake-
enhanced rain showers through Thursday afternoon. By Thursday
night, flow becomes southeast, focusing most of the showers
offshore and/or into western New York. Most of the area will see
dry weather and clearing skies by Thursday evening.
Tonight`s overnight lows will be in the upper 40s to lower 50s
and expect cooler highs in the upper 50s to lower 60s on
Thursday afternoon. By Thursday night, temps will plummet into
the mid to upper 30s and a few spots in the higher elevations of
north-central Ohio may fall near freezing. Stay tuned for
potential frost/freeze headlines.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
A highly amplified pattern will be in place for the end of the week
into the weekend as deep mid/upper longwave troughing persists over
the eastern two thirds of the CONUS downstream of strengthening
mid/upper ridging along the U.S. and Canadian west coasts. This will
cause well below normal temperatures and periods of showers,
including lake-effect/lake enhanced showers, as numerous shortwaves
rotate through the broad cyclonic flow. Starting off on Friday, a
240-250 degree boundary layer flow will mostly keep lake-effect
showers offshore of Erie County, PA, but added slight chance PoPs in
the morning along the lakeshore from eastern Lake County to northern
Erie County in case any showers brush this area. Backing flow ahead
of a shortwave Friday afternoon will end any lake-effect, so dry
conditions are expected Friday afternoon through Friday night. The
shortwave will progress through the central Great Lakes on Saturday
dragging a cold front through the region during the afternoon.
Moisture return ahead of the front is weak given the deep NW flow
aloft, but forcing from a 90-95 knot upper jet will lead to a band
of scattered showers along and ahead of the boundary Saturday
afternoon into early Saturday night, so have chance PoPs moving west-
east across the region, diminishing by Sunday morning.
Highs Friday will be in the mid/upper 50s moderating briefly into
the low 60s ahead of the front Saturday. Lows Friday night will
range from the low/mid 40s with upper 30s/low 40s Saturday night as
post frontal cold air advection kicks in.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Unfortunately for those who do not like cold weather, the chilly
pattern will turn much colder in the extended range. Strong cold air
advection on Sunday behind the aforementioned cold front will drop
850 mb temperatures to 0 to -2 C, so highs will be back down into
the mid/upper 50s. W to WSW flow will again generate some lake-
effect showers over the lake, possibly clipping the lakeshore from
eastern Lake County to northern Erie County, PA, but drier air and
subsidence behind the initial front should keep this disorganized,
so kept PoPs at slight chance. Moisture and cold air depth will both
increase Sunday night as the next shortwave and associated H5 vort
max dive into the western Great Lakes. This will cause lake-effect
showers to increase. WSW boundary layer flow may continue to keep
much of it offshore, but the increasing moisture, convergence ahead
of the associated front, and upper forcing will spread synoptic
showers into northern Ohio and NW PA, so have high chance PoPs in
much of north central and NE Ohio and NW PA by late Sunday night.
This front will move through the region Monday, with the parent
mid/upper shortwave closing off into a closed low over Georgian Bay,
which gradually lifts through Ontario Province Tuesday into
Wednesday. This will lead to a huge mid/upper vortex in the Great
Lakes region through mid week with abundant wrap around moisture and
strong cold air advection supporting lake-effect and lake-enhanced
showers in WNW to NW boundary layer flow. Have likely to categorical
PoPs in NE Ohio and NW PA (highest in the snowbelt) Monday through
Tuesday, so it will be cold and raw with period of showers. Wet snow
will mix in starting Sunday night and especially Monday night and
Tuesday night. Too early to talk accumulations, but this pattern
certainly points toward light accumulations on elevated surfaces.
Coverage of lake-effect showers will gradually diminish Wednesday as
surface high pressure approaches from the west, but deep eastern
CONUS troughing will continue.
Highs Monday will be limited to the mid/upper 40s with low/mid 40s
Tuesday and mid/upper 40s Wednesday. Lows during the early to mid
week period will be well down into the 30, so many places will see a
freeze next week.
&&
.AVIATION /00Z Thursday THROUGH Monday/...
Areas of showers, with embedded isolated thunderstorms observed
across the area this evening. Precipitation coverage will
continue to increase over the next few hours as the upper-level
trough and surface cold front approaches from the west, with
widespread precipitation expected over the next several hours.
Expansive area of precipitation will shift eastward through the
overnight hours, exiting the area by late tomorrow morning.
Initially, conditions will largely be VFR, with
ceilings/visibilities lowering to MVFR with patchy IFR
conditions. Gusty winds could accompany any stronger storms that
develop.
Winds out of the south are observed with speeds of 10-12 knots
and gusts as high as 20 knots. A cold front moves across the
area tonight with a sharp directional change to out of west,
with weakening wind speeds. West-southwest strengthen during the
daytime hours on Thursday to 10-15 knots with gusts up to 20-25
knots.
Outlook...Non-VFR possible with scattered rain showers Saturday
through Sunday.
&&
.MARINE...
The Small Craft Advisory for the western and central basins will
continue through 04Z tonight, mainly for SSW winds of 15-25 knots.
Most of the waves will be over the open lake given this wind
direction. Winds veer to the W and diminish to 10-15 knots behind
the front tonight, before WSW winds increase to 15-25 knots Thursday
afternoon and Thursday night, so an additional Small Craft Advisory
will be needed at that time, likely for the entire lake. Winds
become SW and decrease to 10-15 knots Friday and 15-20 knots Friday
night, veering to W with similar speeds Saturday. W winds will then
average through Sunday night before turning NW and increasing to 15-
25 knots Monday.
Waterspouts will occur at times late this week and especially this
weekend and early next week due to cold air crossing the mild
lakes.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...Small Craft Advisory until midnight EDT tonight for LEZ142>146.
&&
$$
SYNOPSIS...Saunders
NEAR TERM...Maines/Saunders
SHORT TERM...Garuckas
LONG TERM...Garuckas
AVIATION...Saunders
MARINE...Garuckas
Area Forecast Discussion
National Weather Service Des Moines IA
629 PM CDT Wed Oct 12 2022
...Updated for the 00z Aviation Discussion...
.DISCUSSION.../Tonight through Wednesday/
Issued at 329 PM CDT Wed Oct 12 2022
Key Messages:
-- Blustery winds each day through Friday
-- Fire weather concerns, especially western Iowa this afternoon and
Thursday afternoon
-- Continuing to favor dry, cool weather this weekend into next week
Details: GOES-East upper level water vapor imagery shows the trough
digging southeastward into the north central US with a plume of
moisture ahead of surface cold front from Ontario arcing down to the
western Tennessee Valley. With the trough axis east of the forecast
area, we are in the favorable region for ascent of a 150 knot, 300mb
jet streak, which was accurately sampled by the 12z KGGW RAOB.
Further, a shortwave trough apparent in the same GOES imagery is
moving further into Iowa, which is bringing down a mixture of mid
and low level clouds per GOES-East Day Cloud Phase Distinction RGB.
While there is large scale subsidence behind the front, steep lapse
rates in BUFKIT soundings show some potential of weak instability in
the mid-levels. This combined with the aforementioned jet streak and
shortwave is overcoming dry low level air for light rain. Thus have
continued the low chance of showers over northern Iowa this
afternoon. Further, that aforementioned weak instability is enough
for a few rumbles of thunder with lightning detected via the
Geostationary Lightning Mapper so have low chances of thunder this
afternoon as well over parts of Iowa.
Strong winds are also the story this afternoon and will be the next
few days. BUFKIT soundings, particularly from the RAP and HRRR, are
robust in their mixing height upwards of 4km. Winds at the top of
this modeled mixing height would easily reach 45 mph with wind gusts
at KFSD and KSXK around 47 knots late this morning. Therefore,
issued a wind advisory around midday for this afternoon for the
burst of strong sustained winds and wind gusts, which should exceed
40 to perhaps even 50 mph if full mixing is obtained. Temperatures
are a bit lower than expected with the fuller cloud cover and in
some parts of central and southern Iowa, there was a wetting rain
last night/early this morning. So, despite the deep mixing, relative
humidity values have stayed above critical levels in addition to the
fuels needing some time to dry out. Still, with the strong winds
this afternoon, fire weather concerns remain elevated through early
this evening and that is highlighted in the wind advisory as well as
the Special Weather Statement.
Looking into Thursday, strong, gusty northwest winds look to repeat
as the trough closes off in the mid-levels and sets up to spin in
the vicinity of the Ontario province and the western Great Lakes.
Drier air will also move in with dewpoints in the teens and low 20s
common across much of our area by Thursday afternoon. While there
are spotty showers this afternoon, generally under a tenth of an
inch is anticipated so there should be sufficient time with the
winds and the dry air to dry the fuels out by Thursday afternoon.
The current parameters would provide Grassland Fire Danger Index
values generally in the very high category over a portion of our
western tier of counties. This and in coordination with neighboring
offices, have issued a Red Flag Warning for western Iowa where fuels
are largely more cured and because of the expected higher wind
speeds in that part of the state.
The mid-level closed low will move ever so slowly eastward, but
overall Iowa will remain beneath northwesterly, cyclonic flow
through early next week. Conditions should not be as windy on Friday
as the pressure gradient relaxes a bit across the region. A
shortwave trough will rotate around the main low on Friday and try
to bring light showers to parts of the state. Looking at ensemble
guidance, not too excited about chances with Des Moines and Ames
only have 10 to maybe 20% of the 100 members ticking off any QPF.
Much of the rest of the period will continue to favor below normal
temperatures and dry conditions. The caveat of course as previously
mentioned will be if any lobe of vorticity will pass through with
sufficient moisture to bring any showers to the area.
&&
.AVIATION.../For the 00Z TAFS through 00Z Thursday evening/
Issued at 629 PM CDT Wed Oct 12 2022
Main aviation concern will be strong surface winds on Thursday
from the west northwest as gusty conditions develop by midday with
increased mixing. Any ceilings are expected to remain VFR as well
as the visibilities.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 7 PM CDT this evening for IAZ004>007-015>017-
023>028-033>039-044>050.
Red Flag Warning from noon to 7 PM CDT Thursday for IAZ004-015-
023-033-034-044-045-057-070-081-092.
&&
$$
DISCUSSION...Ansorge
AVIATION...Cogil
Area Forecast Discussion
National Weather Service New Orleans LA
855 PM CDT Wed Oct 12 2022
...New UPDATE...
.UPDATE...
Issued at 855 PM CDT Wed Oct 12 2022
Continuing to monitor movement of cold front to our northwest.
Still near a Memphis to Texarkana line at 8 PM CDT, with
scattered thunderstorms just in advance of the front. Well ahead
of that, still seeing a few thunderstorms between McComb and
Natchez moving eastward, somewhat weaker than they were earlier.
Front likely to move into northwest Louisiana over the next couple
of hours. Most reports of severe weather to this point of the
evening to our north and northwest have been large hail.
00z LIX sounding still showed potential for strong thunderstorms
with precipitable water values of 1.91 inches, CAPE values around
2500 J/kg and lifted index of -8. A few areas are likely a little
more stable than that due to earlier convection, but overall,
don`t see a lot of inhibiting factors, other than the lack of
organized lift. With the loss of surface heating, any further
development of thunderstorms is likely to be somewhat elevated,
but that wouldn`t really reduce the hail threat. The Storm
Prediction Center continues to carry a Marginal Risk of severe
weather overnight near and north of the Interstate 10 corridor.
That being said, trends of recent HRRR and RAP runs has been to
bring the convection just ahead of the front to the northwest edge
of our CWA well after midnight then dissipate it. Not going to
give up on the thunderstorm threat quite yet, and will not make
changes to rain chances for now.
Brief window for fog development prior to the arrival of the front
if winds continue to drop off, especially in areas that had rain
earlier. With the front arriving as late in the night as it
currently appears, cooler air not likely to arrive before sunrise.
Don`t see a need to make significant adjustments for overnight
lows, but may refresh hourly temperature/dew point trends.
&&
.SHORT TERM...
(This evening through Thursday night)
Issued at 323 PM CDT Wed Oct 12 2022
Mild warm air advection and moisture transport combined with mid 80
temps continues to support scattered convection across the region.
Most storms will be relatively weak due to overall lack of shear or
a substantial focus. However, instability could be just enough to
support a strong storm or 2. CAMs depiction of whats currently seen
on radar with scattered showers and storms passing west to east
across the CWA through the rest of this afternoon. This diurnally
driven activity will wane as the sun sets. As the cold front,
currently still in central Arkansas, races south overnight, a second
round of storms will be possible. Meso models appear to be in good
agreement that intensity of these storms will decrease as they move
south through the forecast area. Adjustments were made to POPs to
account for this solution.
As post frontal air mass and high pressure builds into the region on
Thursday, rainfall activity clears out and clouds will be on the
decrease. While not looking at much of a cool down, should see temps
fall some. Probably will see more of a drop in lows vs high temps.
&&
.LONG TERM...
(Friday through Tuesday night)
Issued at 323 PM CDT Wed Oct 12 2022
Somewhat drier air will enter the area after the front on Friday
with dewpoints in the 50s before winds become southerly once more
and more moist air returns through the weekend. High temperatures
will be in the mid 80s each day while low temperatures will start in
the mid 50s and gradually increasing with the dewpoints each night
up to the mid 60s by Monday morning.
The upper-level pattern over the next week will be dictated by a
deep, longwave trough over the eastern CONUS with strong ridging
upstream over the Pacific Northwest. This will continue to provide
consistent cold front passages through our area through next week
with the next strong front expected to arrive sometime on Monday
into Tuesday morning. The exact timing/depth of the colder airmass
and convective activity associated with the boundary will ultimately
make a difference in high temperatures being in the 70s or mid 80s.
The post-frontal airmass will be much drier with dewpoints expected
to fall into the 40s by Tuesday. High temperatures are expected to
be in the upper 60s to mid 70s through the remainder of the period
with the coldest low temperatures of the fall expected on Wednesday
and Thursday where some localized areas could drop into the low to
mid 40s.
Rain chances will be limited by the initial post-frontal airmass and
subsidence on the backside of the exiting shortwave trough over the
eastern CONUS through Saturday before PoPs begin increasing on
Sunday ahead of the next cold front. Rain chances will be highest on
Sunday afternoon through the day on Monday as moisture return
reaches its peak and forcing for ascent becomes more prominent as a
cutoff low within the subtropical jetstream approaches from the
west. Post-front on Tuesday, the much drier airmass should stabilize
the atmosphere once again leading to near-zero chances of rain
through the rest of the period. TJS
&&
.AVIATION...
(00Z TAFS)
Issued at 646 PM CDT Wed Oct 12 2022
All terminals currently VFR. Cold front currently well to the
northwest near a KSTL-KDFW line moving southeast.
In the near term, main concern will be convection, with a cluster
of TSRA along the Louisiana-Mississippi border north of KBTR
moving east. Some question whether this convection will make it as
far east as KMCB before dissipating. Will carry VCTS for now
there between about 02-05z. Probably will be a period ahead of the
front where wind gradient weakens with some low clouds/fog
possible. Ceilings, and possibly visibilities, likely to drop to
IFR for a few hours before the front arrives with the potential
for SHRA and perhaps shallow TSRA. Current timing on the frontal
passage would be around 09z for KMCB, 12-15z for terminals near
the Interstate 10-12 corridors and closer to midday for KHUM. VFR
behind the front through the end of the forecast period.
&&
.MARINE...
Issued at 323 PM CDT Wed Oct 12 2022
A cold front will approach and push through the local area on
Thursday morning. Cold air advection doesn`t look to be very
impressive with this system, so mainly looking at a wind shift and
winds 10-15kts with seas 2-4 ft. Nocturnal winds could approach 15-
20 kts at times, so exercise caution headline may be needed. Post
frontal surface ridge will quickly slide east and lend to onshore
flow through the weekend before the next system.
Moving into next week, as another cold front approaches, pressure
gradient winds will gradually increase through Monday and Wednesday
where winds over land will peak around 10 to 15 knots. Coastal
waters will be closer to 20 to 25 knots with higher gusts on Tuesday
which could warrant small craft advisories as we get closer in the
timeline.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 65 82 54 82 / 60 0 0 0
BTR 68 86 57 86 / 50 10 0 0
ASD 66 86 55 85 / 40 10 0 0
MSY 70 85 64 83 / 40 10 0 0
GPT 69 85 58 83 / 40 10 0 0
PQL 68 84 54 82 / 30 10 0 0
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&
$$
SHORT TERM...ME
LONG TERM....TJS
AVIATION...RW
Area Forecast Discussion
National Weather Service Nashville TN
834 PM CDT Wed Oct 12 2022
...New UPDATE...
.UPDATE...
Issued at 830 PM CDT Wed Oct 12 2022
We`re finally out of the woods regarding any severe threat. A few
showers and thunderstorms are still moving into our southwest
counties, but these should only offer a few rumbles of thunder as
surface based CAPE has all but vanished in these areas. Cooler
temperatures and dry air will move into the region over the next
12 hours leaving today`s storms all but another distant memory.
&&
.SHORT TERM...
(This afternoon through Thursday Night)
Issued at 210 PM CDT Wed Oct 12 2022
Convection is ongoing early this afternoon in the eastern half and
a line moving into the northwest ahead of a cold front. CAMs have
struggled to decide on a secondary line of storms closer to the
front this evening that may bring additional chances for strong to
severe storms, especially in the southwest. But, instability will
begin to weaken this evening, and the primary severe threat
remains this afternoon through mid evening or so. Current data
shows MLCAPE values around 500 to 1000 J/kg, and deep layer shear
40 to 50 knots. The HRRR and NAM suggest some bowing segments will
be possible along the line of storms, and would support more of a
damaging wind gust threat. Winds are the primary threat with any
strong to severe storms that develop, but hail and even an
isolated tornado or two can not be ruled out, especially later in
the afternoon to early evening when low level wind shear is
expected to increase with the approaching trough and cold front.
Showers and storms should move off to the east after midnight with
the severe threat likely coming to an end in the late evening.
After the front moves through tonight, dry air will continue to
advect into the mid state during the day. Northwest winds around
10 to 15 mph and gusts to 25 mph will help low level mixing, and
may bring drier air to the surface as well. This will increase the
fire weather threat in the afternoon with min RH values in the 20
to 25 percent range across the area.
&&
.LONG TERM...
(Friday through next Wednesday)
Issued at 210 PM CDT Wed Oct 12 2022
Dry conditions will continue for the remainder of the work week,
but a Midwest trough looks to bring another cold front through
this weekend, with additional chances for showers and
thunderstorms Saturday afternoon through the day Sunday. Likely
will not be a washout, but models are showing slightly different
solutions on timing for the weekend. The coldest air so far this
season will follow the front early next week, with highs on
Tuesday only in the 50s and lows in the 30s Tuesday morning. Lows
in the 20s will be possible Wednesday morning in low lying areas
and on the Plateau. Models do show 850mb temps around -2C to -6C
Tuesday morning and Wednesday morning, so freezing temps look
likely both of those mornings.
&&
.AVIATION...
(00Z TAFS)
Issued at 737 PM CDT Wed Oct 12 2022
Storms have moved east of all terminals at this hour. Expect
showers to continue at CSV for a few more hours with intermittent
MVFR cigs and gusty winds out of the southwest. Other terminals
will see winds around 5 to 10 knots for much of the overnight, but
storms are expected to remain south of all terminals. Rainfall may
provide moist enough ground conditions to allow some fog to
develop, though the sustained light winds may keep impacts to a
minimum. Expect VFR conditions after 14z at all sites.
&&
.PRELIMINARY POINT TEMPS/POPS...
Nashville 56 72 43 76 / 50 0 0 0
Clarksville 51 71 41 76 / 30 0 0 0
Crossville 55 64 38 65 / 100 10 0 0
Columbia 55 71 41 76 / 70 0 0 0
Cookeville 56 66 40 69 / 80 10 0 0
Jamestown 54 63 40 65 / 100 10 0 0
Lawrenceburg 56 70 42 74 / 70 0 0 0
Murfreesboro 56 71 40 75 / 50 0 0 0
Waverly 51 70 41 75 / 40 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE.......Unger
SHORT TERM...Barnwell
LONG TERM....Barnwell
AVIATION.....Whitehead
Area Forecast Discussion
National Weather Service Pendleton OR
839 PM PDT Wed Oct 12 2022
.UPDATE...Another quiet night is underway with few weather
concerns. A ridge of high pressure remains in control of the
region. Satellite imagery shows clear skies with high cirrus
passing to our north and east. Winds are light aside from some
lingering north to northwest winds up to 10 mph in central Oregon
that should decrease in the next hour or two. Temperatures look on
track to be similar to last night. Current forecast is in good
shape. Made a few minor temperature adjustments to bring them
closer to last night`s temperatures. Forecast update is already
out. Perry/83
&&
.PREV DISCUSSION... /issued 450 PM PDT Wed Oct 12 2022/
AVIATION...00Z TAFs...VFR conditions are expected all sites over
the next 24 hours. Winds will remain light, 10kts or less, and
skies clear. Areas of haze has cleared out, and the HRRR smoke
model doesn`t indicate widespread return of haze for now, but
wildfires in the region could bring it back sooner rather than
later with weak flow. Goatley/87
PREV DISCUSSION... /issued 126 PM PDT Wed Oct 12 2022/
SHORT TERM...Wednesday through Friday...Satellite imagery showing a
few high clouds streaming primarily across the northern periphery of
our forecast area. A thin shield of elevated smoke is also visible
pooling into the Basin as wildfires continue to rage across the
region in light of exceedingly dry conditions over the last several
weeks. Unfortunately, models suggest this unseasonably warm and dry
weather will persist through at least the end of next week as high
pressure centered just offshore to our west prolongs this dry
pattern. A low centered over the SW US will ensure a rex block that
will keep the high pressure in its place. Could see haze becoming
more prominent as a result over the next several days, otherwise
sensible weather concerns are limited. Highs in the mid 70s for most
of our population centers, with mostly upper 30s into 40s for
overnight lows. Elevated valleys could see temps dip into the 20s.
Evans/74
LONG TERM...Saturday through Wednesday...Deterministic and
ensemble models continue to be in good agreement regarding the
ongoing upper level ridge persisting through the extended period.
This will continue the dry warm mild weather pattern with above
normal high temperatures running about 10 degrees above normal
through the weekend. An upper trough will approach the coast
first of the week but then drop south and form a closed low
off the California coast. This will however weaken the ridge
and move its center over the Rockies and turn the flow
aloft to southwesterly. In return, this will cool temperatures
slightly by a few degrees but still remain 5-10 degrees above
normal.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 44 75 44 76 / 0 0 0 0
ALW 45 76 46 76 / 0 0 0 0
PSC 46 76 46 76 / 0 0 0 0
YKM 43 78 42 78 / 0 0 0 0
HRI 45 77 44 77 / 0 0 0 0
ELN 41 79 42 79 / 0 0 0 0
RDM 33 78 38 80 / 0 0 0 0
LGD 38 78 39 77 / 0 0 0 0
GCD 43 83 43 82 / 0 0 0 0
DLS 47 82 48 82 / 0 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
&&
$$
SHORT TERM...83
LONG TERM....91
AVIATION...87
Area Forecast Discussion
National Weather Service Blacksburg VA
855 PM EDT Wed Oct 12 2022
.SYNOPSIS...
A cold front will move into the region from the west late
tonight and slowly progress eastward through the area
Thursday. Showers will accompany the front overnight and
Thursday morning with isolated thunderstorms possible this
evening in the west and Thursday afternoon across the Piedmont.
Cooler temperatures will follow for Friday into the weekend as a
broad area of low pressure aloft evolves across the Great
Lakes. A secondary push of cold air will arrive early next week
along with another chance for showers.
&&
.NEAR TERM /THROUGH THURSDAY/...
As of 856 PM EDT Wednesday...
Continue to shape pops and weather for this evening into
Thursday using radar trends and model solutions. Leaned pops
towards a blend of NAM, HRRR and Hires-ARW. In general, trend
has been to decrease pops and tried to highlight the window
with best chances overnight into Wednesday morning. A cold
front to our west in the Ohio Valley will slowly moving east
tonight into Thursday. The RNK 00z sounding showed that the
PWATS have climbed to 1.06 inches with a south to southwest
flow. Elected to add more fog overnight especially in the
western mountains. Low temperatures tonight will be mild with
readings from around 50 degrees in the northwest mountains to
near 60 degrees in the Piedmont.
Previous discussion:
As of 530 PM EDT Wednesday...
Made some adjustments to pops and weather for this evening into
tonight using latest radars and their trends. In general, rain
has been light this afternoon into this evening with the drier
air across our region. As a cold front will push through the
region late tonight and Thursday, rain will become more
widespread and heavier. Modified temperatures utilizing the
latest surface obs,their trends and blended in the NBM. More
changes later tonight.
Previous discussion:
As of 200 PM EDT Wednesday...
Cold Front On Track to Bring Widespread Showers to the Area
Tonight and Thursday...
Broad troughing will develop over and just north of the Great
Lakes and dominate the weather scene through the weekend. Large
scale cyclonic flow will evolve across the eastern two-thirds of
the U.S. as a result. A cold front will push through the region
late tonight and Thursday bringing widespread rain and isolated
thunderstorms this evening in the west and again more likely in
the Piedmont tomorrow. QPF has been ramped up quite a bit from
previous indications due to better isentropic lift and slightly
slower frontal movement along with less indication of
southeastern U.S. convection limiting precipitation further
north. Rainfall amounts are expected to be in the 1/2 to 1 inch
range now across much of the CWA with enhancement, as usual,
along the Blue Ridge. Most of the rain will fall overnight and
early Thursday.
Timing for any strong to severe storms in the west overnight is
poor and thus not expecting such threat in the west. By Thursday
afternoon, the front will be located generally along/east of a
LYH-MTV-UKF line. Afternoon surface temperatures are expected to
be in the lower to mid 70s ahead of the front with dewpoints in
the 60s. Thus, SPC has depicted a "marginal risk" for severe
thunderstorms across the eastern most tier of counties for
Thursday afternoon. The more likely threat for severe will take
place further east along the I-95 corridor and the coastal
plain. The latest NAMNest has backed off on a line of convection
in the eastern areas Thursday afternoon, but a small threat
still exists for such in those areas if the timing, sunshine,
heating, and moisture all align ideally.
Temperatures will be mild tonight as the clouds and
precipitation overspread the area, although initially there will
be some evaporative cooling from the rain into the antecedent
dry air mass. Lows mainly in the 50s. High temperatures Thursday
will only be in the 50s to lower 60s west but potential for mid
70s ahead of the front in the far eastern areas.
/Confidence Levels in Forecast Parameters/
- Moderate Confidence in Temperatures,
- High Confidence in Precipitation Probabilities,
- Moderate Confidence in Wind Direction and Speed.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 215 AM EDT Wednesday...
Mild and dry middle of the week, rain arrives Thursday...
Behind a cold front on Thursday, surface high pressure will fill in
quickly over us, returning the area to dry weather for most of the
weekend. A large sweeping upper trough remains centered over the
Great Lakes region, and will usher a weak shortwave and cold front
through the Mid-South and into the Mid-Atlantic. Moisture will be
lacking, so most precipitation associated with this system will
be light and fall west of the Blue Ridge.
Temperatures in this period will be warm for the time of year. Highs
in the mid-60s on Friday will increase to highs in the 70s for
almost the entire CWA on Saturday.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 215 PM EDT Wednesday...
Punch of cold air follows early week cold front...
The deep and persistent upper trough centered over the Great Lakes
will continue to pull fronts through the area, bringing a brief bout
of precipitation Sunday afternoon and evening. As with earlier in
the weekend, rainfall amounts will be light, but could spread over
the entire CWA.
Some cold air will follow the front and sit over the
area as the upper trough trudges eastward and places us in northwest
flow in building surface pressure. Temperatures take a nosedive
Monday night, bringing western areas close to or below freezing,
especially near the WV/VA state border. The cold is here to stay,
however as northwest flow continues to hold temperatures down. Highs
will be below normal, and overnight temperatures will drop below
freezing for most of the CWA, save mostly Piedmont areas.
&&
.AVIATION /01Z THURSDAY THROUGH MONDAY/...
As of 737 PM EDT Wednesday...
Low clouds,rain and fog will hinder aviation operations
Overnight into Thursday.
Broad upper trough will develop across the Great Lakes and
dominate the East through the weekend. A cold front to our west
in the Ohio Valley will slowly move east tonight into Thursday.
This front will bring numerous showers and isolated
thunderstorms to our region. Isolated strong thunderstorms are
possible east of U.S. 29 Thursday afternoon.
Ceilings will lower into the MVFR range this evening as
rain spreads in from the south and southwest. Ceilings will
lower into the IFR-LIFR range overnight through midday Thursday.
As the cold front moves through, ceilings will generally
improve to MVFR Thursday morning. Visibilities will remain VFR
until showers arrive. Look for primarily MVFR visibilities with
brief periods of IFR-LIFR late night/early morning in heavier
rain showers and fog.
Southeast winds at 5-10 mph with low end gusts southeast WV/far
southwest VA this evening becoming mainly southeast overnight,
then southwest to west 10-20 mph behind the front. Wind gusts to
25kts are possible with the frontal shower activity.
Moderate Confidence in Ceilings,Visibilities, and winds during
the taf period.
Extended Aviation Discussion...
VFR conditions and drier air return by Thursday night into
Saturday. Unsettled conditions with low pressure aloft will
linger through the weekend. Isolated MVFR showers are possible
again beginning Saturday night into Sunday. A few showers may be
possible especially in the northwest Monday.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...KK/RAB
NEAR TERM...KK/RAB
SHORT TERM...VFJ
LONG TERM...VFJ
AVIATION...KK/RAB