Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/16/23
Area Forecast Discussion
National Weather Service Birmingham AL
803 PM CST Wed Feb 15 2023
...New SHORT TERM...
.SHORT TERM...
(Tonight through Thursday)
Issued at 802 PM CST WED FEB 15 2023
Latest RAP mesoanalysis and GOES-East water vapor imagery show a
broad corridor of southwest mid- to upper-level flow stretching from
the Western Gulf of Mexico northeast through the Mid Atlantic. This
coincides with a subtropical ridge centered near the Bahamas and an
upper-level low at the base of a positively-tilted trough positioned
from near the Four Corners through the Upper Midwest. Underneath
this lies a more southerly low-level jet, mainly positioned near the
Lower Mississippi Valley. This is transporting warm, moist air
northward across a warm sector now established across much of the
Mid and Deep South and into the ArkLaTex region, where cyclogenesis
will occur overnight. A scattering of thunderstorms can now be
observed across central Mississippi and northwest Alabama where
MLCAPE of 500-1,000 J/kg resides. This convective activity is
expected to continue a north-northeast advancement overnight,
eventually focusing along the I-40 corridor to our north. There`s an
opportunity, albeit low, for a strong or severe thunderstorm to move
across our northwestern counties overnight. Given the established
warm sector and ~50 kts eff. bulk shear, we`ll be keeping an eye on
RADAR for these areas.
By tomorrow morning, the surface low is expected to propagate
northeast from the ArkLaTex toward the Ohio Valley in response to a
mid-level perturbation ejecting across the Plains. This disturbance
will eventually "shear out", but the parent trough will continue
east along with a strengthening 500 mb jet to our north. The
associated cold front will also move east into Deep South. Ahead of
this cold front will reside the warm sector characterized by low to
mid 60s dewpoints into the daytime hours. This will foster up to
~1,500 J/kg MLCAPE given afternoon temperatures in the 70s and pre-
convective mid-level lapse rates ~7 C/km. These thermodynamics
typically result in robust updrafts for our area, especially in the
cool season. Eff. bulk shear ~50 kts will remain in place through
the period which suggests strongest updrafts will organize, most of
which developing mesocyclones.
Despite what appears to be a mixed convective mode, all severe
hazards remain on the table tomorrow with damaging winds up to 70
mph, large hail, and tornadoes - some significant. The strongest
severe impacts should remain associated with any discrete/semi-
discrete supercells that form ahead of the front, or any bowing
segments. The best overall environment for this appears to be across
the western 2/3 of Central Alabama where severe ingredients best
overlap with modest height falls during the early to late afternoon.
This also includes the best access to low-level CAPE and wind
shear/hodograph curvature - various forecast soundings suggest 200-
300 m2/s2 0-1 km SRH. Thunderstorms likely grow upscale and
aggregate into a more linear convective system thereafter,
especially overnight. However, aforementioned severe hazards will
continue across the rest of Central Alabama despite a decreasing
trend in severe parameters. Everyone across Central Alabama needs to
remain weather aware tomorrow. Conditions improve with the departure
of the low-level jet overnight and the arrival of the cold front.
This will provide strong cold air advection into Friday morning.
No changes have been made to the HWO or severe impact messaging at
this time.
40/Sizemore
&&
.LONG TERM...
(Friday through next Tuesday)
Issued at 226 PM CST WED FEB 15 2023
Colder and drier airmass will work into the area through the rest
of the day on Friday, which will carry over into the weekend.
Upper level flow becomes largely zonal as we transition into next
work week. This allows for a moderating temperature trend (hello
80s!), while also keeping deep moisture from returning in full
force to central Alabama. A series of upper level impulses in the
fast zonal flow could bring brief bouts of scattered showers. But
forcing appears rather weak with each one, and the timing of each
impulse is also low confidence. Will therefore go with slight
chance to chance (at most) of showers during this time frame.
/61/
&&
.AVIATION...
(00Z TAFS)
Issued at 544 PM CST WED FEB 15 2023
MVFR/VFR flight conditions expected through ~06z with ceilings
025-050, along with a few light rain showers across the northern
terminals through ~03z. Ceilings are forecast to fall to MVFR at
all terminals after ~06z which will persist through tomorrow
morning in some fashion. Southerly winds will also increase to
10-15 kts with gusts ~20 kts overnight.
For tomorrow, a storm system is forecast to move into Central
Alabama after ~18z. Strong to severe convection is forecast and
will impact all terminals at some point during the afternoon and
evening hours. Despite the opportunity for VFR conditions ~21z,
this will be the primary flight impact along with strong southerly
wind gusts of 25 kts or more.
40/Sizemore
&&
.FIRE WEATHER...
Widespread showers and thunderstorms are forecast to move through
the area Thursday and Thursday night with a cold front. Cooler
and drier air arrives Friday with afternoon RH values in the 35 to
45 percent range. 20ft winds will be out of the northwest on
Friday around 12 mph.
&&
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 60 74 40 49 / 40 100 100 10
Anniston 60 75 43 53 / 20 100 100 10
Birmingham 63 76 39 50 / 30 100 100 0
Tuscaloosa 64 76 39 51 / 30 100 100 0
Calera 62 76 41 52 / 20 100 100 10
Auburn 60 73 48 58 / 10 50 100 40
Montgomery 62 78 48 58 / 10 70 100 20
Troy 62 77 50 61 / 10 40 100 30
&&
.BMX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...40/Sizemore
LONG TERM....32
AVIATION...40/Sizemore
Area Forecast Discussion
National Weather Service Quad Cities IA IL
835 PM CST Wed Feb 15 2023
.UPDATE...
Issued at 829 PM CST Wed Feb 15 2023
Early looks at the latest 00z guidance which is purely from CAMs,
shows that the placement of the warning for heavy snow continues
to be supported by guidance. In fact, the majority of new guidance
supports the higher end of our expected snow amounts in the
warning.
Also, concerning, is the depiction of significant freezing rain,
in our southern counties. For now, our forecast shows this falling
as sleet and snow in grids, but not freezing rain. That will be a
key feature of the forecast we`ll address into tonight`s forecasts
cycle/issuance. For now, our advisory for snow and sleet in the
south is ok, but if this trends toward ice, we could have to go
with a warning for ice accumulation.
ERVIN
&&
.SYNOPSIS...
Issued at 223 PM CST Wed Feb 15 2023
Persistent strong westerly winds and clouds has kept temperatures
a few degrees lower than previously forecast. 18z MSAS analysis
shows pressure gradient relaxing and temperatures in the 30s
locally. Water vapor satellite loops show closed low rotating
over the four corners region, with diffluent flow ahead of it.
This wave will eject into the Plains and bring us wintry weather
on Thursday.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 223 PM CST Wed Feb 15 2023
Key Messages:
1. Latest models show a slight southeast shift in the heaviest
snow axis from hi-res model output. Regardless, a strong winter
storm will bring impacts to the CWA, with widespread accumulating
snow. Snow covered roads and sidewalks during the Thursday AM
commute are still expected.
Complex winter setup with incoming storm, with a slight southeast
shift in heaviest snow axis noted by latest model data. Model
soundings, max wetbulb aloft, and thermal profiles suggest the
dominant ptype for the entire CWA will be snow, with a brief
wintry mix at onset across west central IL. A dprog/dt of the 12z
GFS and NAM shows a slightly slower surface low track and 500mb
low track, so not anticipating precipitation beginning before
midnight tonight. Moisture transport and mid level fgen really
increases overnight between 09-15z. In addition, high omegas
within the DGZ are shown in the latest RAP during the AM commute
with large dendrites. Despite the warm ground/pavement temps,
snowfall rates between a 0.75"/hr to 1.5"/hr will be enough to
overwhelm the warm ground and accumulate. This system will have
higher SLRs than last week`s system resulting in a drier fluffier
snow. With model QPF values between 0.3 tenths and 0.5 tenths of
an inch and SLRs between 12:1 to 15:1; results in 4 to 7 inches of
snow. The heavier totals will likely be in a narrow band within
the warning area.
If that wasn`t enough, a tightening pressure gradient is
also expected as the low tracks into southeast IL by 18z. Strong
north winds between 15-25 mph, with gusts over 30 mph will be
possible. This may cause blowing and drifting snow on east west
roads during the PM commute, especially in open and rural areas.
Snow will begin to rapidly diminish from west to east by late
afternoon and evening.
.LONG TERM...(Thursday night through Wednesday)
Issued at 223 PM CST Wed Feb 15 2023
Key Messages:
1. Cold and dry Friday with sunny skies.
2. Zonal flow to bring quiet weather with above freezing
temperatures this weekend, melting much of the newly fallen snow.
3. Chances of precipitation return middle of next week.
Thursday night-Friday...1031mb surface high and rising heights
aloft will bring clearing skies overnight. Temperatures will drop
into the single digits to lower teens. Some readings near zero
cannot be ruled out in areas within the newly fallen snow. Wind
chills in the single digits to teens below zero will be possible
before 10am Friday. Below normal temperatures and sunny skies will
be norm Friday, with highs in the middle 20s to lower 30s.
Friday night-Tuesday...zonal flow aloft will bring above freezing
temperatures during the day and below freezing readings overnight
during this period. Plentiful sunshine and quiet conditions are
forecast. With dewpoints rising into the upper 20s to middle 30s,
quite of bit of melting snow is expected. Breezy southerly winds
will be possible on Sunday.
Tuesday night-Wednesday...an increasing jet and baroclinic zone
across the Plains will bring the next chance of precipitation to
the local area. Model differences in timing and strength of the
next wave and thermal profiles preclude changing slight chance to
chance PoPs at this time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 522 PM CST Wed Feb 15 2023
Persistent MVFR stratus remains over Iowa and Illinois, as well as
southern Wisconsin. This stratus could thin this evening, but no
matter what, we will see the onset of a winter storm between 06z
and 12Z over eastern Iowa and western Illinois. This storm will
product LIFR conditions in moderate snow and blowing snow through
the day on Thursday, with winds of 15 to 25 kts from the
northeast to north through the day. This winter storm should move
off, with improving visibility around 22-00Z tomorrow evening.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...Winter Weather Advisory from midnight tonight to 6 PM CST
Thursday for Buchanan-Delaware-Des Moines-Lee-Van Buren.
Winter Storm Warning from midnight tonight to 6 PM CST Thursday
for Benton-Cedar-Clinton-Dubuque-Henry IA-Iowa-Jackson-
Jefferson-Johnson-Jones-Keokuk-Linn-Louisa-Muscatine-Scott-
Washington.
IL...Winter Weather Advisory from midnight tonight to 6 PM CST
Thursday for Bureau-Hancock-Henderson-Henry IL-McDonough-
Mercer-Putnam-Warren.
Winter Storm Warning from midnight tonight to 6 PM CST Thursday
for Carroll-Jo Daviess-Rock Island-Stephenson-Whiteside.
MO...Winter Weather Advisory from midnight tonight to 6 PM CST
Thursday for Clark-Scotland.
&&
$$
UPDATE...Ervin
SYNOPSIS...Gross
SHORT TERM...Gross
LONG TERM...Gross
AVIATION...Ervin
Area Forecast Discussion
National Weather Service Green Bay WI
903 PM CST Wed Feb 15 2023
Updated aviation portion for 06Z TAF issuance
and new information added to update section
.UPDATE...
Issued at 851 PM CST Wed Feb 15 2023
The early-arriving 00Z guidance has generally edged back north a
bit with the snow band tomorrow. But timing has also slowed, and
when that occurs this close to the event it often means the system
isn`t going to produce as much precipitation as earlier expected.
The going forecast of keeping most of the snow from KOSH to KWNW3
south looks right on target. So won`t be making any changes to
the snow amount forecast, but will be slowing the northward
advance of the snow just a bit.
Updated product suite will be out ASAP.
&&
.SHORT TERM...Tonight and Thursday
Issued at 302 PM CST Wed Feb 15 2023
Forecast focus in the short term revolves around next system
approaching the forecast area on Thursday.
Bottom line is that the trend with the upcoming system has been
consistent with keeping the primary significant accumulating
snowband just to the south of the forecast area on Thursday.
Nearly all of the deterministic model guidance except the GFS has
focused the primary forcing and greatest snowfall accumulations
along an axis from roughly MSN to near or just north of MKX. The
mean axis of the heaviest snowband from the NBM blended guidance
is quite similar with the the axis forecast from roughly MSN to
MKX with a sharp gradient in snowfall amounts to the north.
Higher resolution CAMS have been furthest south with the HRRR and
RAP forecasting virtually nothing for our southern counties.
The southern trend in the last several model cycles seems to
make sense as on the synoptic scale, the northern and southern
stream remain somewhat disjointed. The northern stream flow seems
to have trended flatter (more zonal) just north of the forecast
area which is not allowing the southern stream shortwave impulse
to strengthen appreciably and work further north. As a result, the
southern stream shortwave is strongly positively tilted and
somewhat strung out from southwest to northeast with unimpressive
surface development. The primary mesoscale forcing mechanism is
the result of focused 850-700 frontogenetic forcing within
the low-level deformation zone over the southern half of
Wisconsin. The frontogenetic signal has been fairly robust, thus
associated mesoscale vertical motion is the primary driver in the
snowband formation late tonight into Thursday. As is typically
the case with frontogentically forced precipitation, there is
also notable mesoscale subsidence north of the primary band which
often results in a very sharp northern cutoff in the precipitation.
This subsidence is manifesting itself in various model soundings
from the RAP and NAMNEST via persistent dry layer in the 850 to
750 layer over the northern Fox Valley through most of the day on
Thursday. The column does quickly moisten sufficiently as you head
south and east into Manitowoc County. As has been mentioned
previously, this event is rather similar to the snowfall event
from last Thursday in terms of the overall synoptic pattern and
the nature of the forcing. The main difference in the current
system is that the airmass is colder and snow ratios will be
closer to 15:1 (rather than 8:1). There will also be an increasing
northeasterly boundary layer wind component on Thursday which may
introduce some lake enhancement, but favorable trajectories into
Manitowoc County are short-lived before turning more northerly by
00Z Friday. So bottom line, latest guess is that perhaps 2-4
inches of snow will be possible for the southeast half of Manitowoc
County with considerable lesser amounts as you head northwest
into the northern Fox Valley with perhaps just a few tenths over
northern Brown, Outagamie to Waushara counties. Opted not to
issue an advisory for Manitowoc County at this time given the
somewhat weaker trend, more southern trend and the fact that the
snowband will be quite narrow and difficult to nail down the
location.
As far as temperatures for Thursday, will be cooler than past
several days with highs near 20 far north to the upper 20s near
Lake Michigan. Northeast winds will also become rather gusty
on Thursday as the system passes to out south. Depending on how
much snow accumulates over our southeast counties, some blowing
and drifting now would appear likely with the primary impacts in
the 16Z to 00Z time frame which will impact the evening commute
there.
.LONG TERM...Thursday Night Through Wednesday
Issued at 302 PM CST Wed Feb 15 2023
On Thursday night, system will quickly move to the east of the
forecast area with skies slowly clearing after midnight. Friday,
should be seasonably cold day with a fair amount of sunshine with
highs mostly in the 20s and lows in the teens.
Generally benign weather for most of the extended with large-scale
flow becoming more zonal with generally weak, fast moving and
transient shortwave impulses moving through the flow. These
systems will pass generally north of the western Great lakes with
glancing blows with some light frontal precipitation through next
Monday. Temperatures will likely warm to above normal into the
30s ahead of these system with overnight lows mostly in the teens
and 20s.
Some early signals of a more substantial system toward mid week.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 851 PM CST Wed Feb 15 2023
Low clouds (MVFR cigs) will continue to be the main aviation
forecast issue through tonight. A fairly expansive deck of clouds
with cigs 2-3K ft was across the area at dusk, but clearing advanced
east across much of the southern half of the area after sunset.
Low clouds have begun advancing back south into this area as winds
veer. So mainly MVFR ceilings are anticipated by midnight and
through the rest of the night. The low clouds are expected to
remain across the area tomorrow as snow slowly spreads into east-
central Wisconsin from the south.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE.........Skowronski
SHORT TERM.....ESB
LONG TERM......ESB
AVIATION.......Skowronski
Area Forecast Discussion
National Weather Service Gray ME
905 PM EST Wed Feb 15 2023
.SYNOPSIS...
Temperatures remain above average through the week before
peaking tomorrow as ridging builds along the East Coast. A
strong cold front crosses the area on Friday, bringing an end to
the near record warmth. This front will bring mostly rain to
the region with cooler temperatures arriving on Saturday. High
pressure builds across New England for next weekend, with warmth
likely returning early next week once the high slides offshore.
&&
.NEAR TERM /THROUGH THURSDAY/...
9:05PM Update... Quick update to account for the localized
radiational cooling. Temperatures range widely across the area
from the upper 20s to the low 50s. The radiational cooling is
likely to only last a few more hours before the wind starts to
mix out the cooler pockets. Otherwise, the forecast remains on
track at this time.
6:55PM Update... Refreshed temps and POPs for tonight with this
update. Sheltered valleys are cooling quickly with clear skies
and light winds, while other areas remain in the mid 50s. No
model is handling this entirely, so mainly the HRRR was used to
try to capture some of the localized cool spots. An area of
showers is likely to scrape along the Canadian border late this
evening, so POPs were raised slightly there for the shower
activity. Still expecting winds to increase later tonight, so
low temps should be achieved this evening before rising again
once the wind picks up.
Previous...
Visible satellite imagery this afternoon shows partly to mostly
sunny skies across southern NH with gradually increasing cloud cover
as you head north and east. These breaks in the cloud cover across
southern areas has allowed temperatures to warm to near 60 degrees
while areas where the clouds remain are still primarily into the
40s. Southwesterly winds have become gusty in spots where surface
warming has helped to strengthen the low-level lapse rates and this
will continue to be the trend through the remainder of the
afternoon. Other than some scattered showers across the mountains
and near the Kennebec River Valley most areas will remain dry
through the remainder of the day.
A weak surface cold front and associated mid-level trough will swing
across the region tonight, although it will bring little in the way
of sensible weather impacts. The only real area of interest
continues to be for a potential period of strong downsloping winds
overnight along the southeastern slopes of the White Mountains and
Western ME Mountains as a 50-60 kt LLJ moves through and Froude
Numbers increase to around 1.0. As a result, the Wind Advisory
remains in effect for the expectation of wind gusts up to 45-50 mph
close to the mountain slopes. Temperatures overnight may be a little
tricky as some guidance including the HREF indicates a period of
mainly clear skies, which depending on cloud cover could allow for a
few hours of good radiational cooling conditions. Expectations
though is that most locations will not fully decouple, which
brings lows down into the 30s to lower 40s from north to south.
&&
.SHORT TERM /THURSDAY NIGHT/...
Clouds will increase from southwest to northeast on Thursday as low
pressure tracks across the Ohio River Valley along a semi-stationary
warm frontal boundary that will extend to southern New England.
Ahead of this system very warm 850 mb temperatures up to around +6C
and 925 mb temperatures approaching +7C will provide the potential
for record high temperatures to be approached or exceeded at
Portland, Concord, and Augusta with highs reaching the 40s
across the north to near 60 degrees in southern NH. The majority
of the day will be dry but there will be an increasing threat
for scattered showers late in the day, especially across
southwestern NH.
Widespread rainfall is then expected on Thursday night as low
pressure crosses near the region or just to our south along
with an associated cold front. The majority of this will fall as
plain rain but across the mountains, a mixture of snow and rain
is likely. An increasing warm nose aloft between 3-5k ft also
introduces the potential for a period of freezing rain and sleet
across the far north, and light accumulations are possible
resulting in slippery travel as colder air begins to move south.
Otherwise, lows will range from the upper 20s across the north
to the middle 40s in southern NH. Fog is also likely to develop
overnight as winds decrease and there could even be a rumble of
thunder towards daybreak on Friday as increasing mid- level
lapse rates collocate with negative showalter indices across the
south and coast.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Overview: Low pressure will slide east Friday, with warm and
dry conditions expected for the weekend. The next chance for
precipitation materializes Monday night as two streams converge
near northern New England. The pattern becomes active and cooler
into the middle of next week.
Details: Low pressure will be transiting much of New England
Friday, bringing widespread precipitation to the region. The
system is progressive, which should result in a cutoff time in
early evening.
As far as precipitation type, have continued a bit of a
southerly trend in freezing/frozen precip once temps peak in the
morning. Blended some NAM guidance into continuing NBM,
particularly in western ME where sfc damming could keep very low
levels below or at freezing. This means a few more hours of
freezing rain will be possible in the western ME mountains,
particularly the upper Kennebec Valley.
With the low departing and cold air sweeping behind, warm nose
aloft erodes and precip type should trend towards snow first in
western areas and then across the foothills to the coast by mid
to late Friday afternoon.
Because the system is relatively flat, there should be a finer
region of continuous stratiform precipitation, with otherwise
showery modes in the warm sector. This brings a QPF max across
the mountains and foothills, with lighter values into the
interior and coast. Will continue to monitor any further track
trends, but largest shield of precip appears to remain north and
west until the storm center ships NE.
Will also need to be aware of wind as the front passes Friday
morning. Luckily, low level inversion should keep these winds to
higher elevations, but could still bring some isolated power
outages across northern NH and western ME due to any wet
snow/ice on trees being blown around. Gusts up to 30 mph will
be possible in the foothills and coast and southern NH, with
gusts up to 45 possible at higher elevations. Higher summits of
the Whites may gust over 100mph as the front passes. Winds
slacken into the afternoon, shifting NW.
A ridge of high pressure moves in Saturday. This will bring
cooler, fair weather for a day. A weakening disturbance will
approach from the NW on Sunday, but should only bring greater
cloud cover for an otherwise warmer day with highs in the 40s
returning to southern NH up the interior of Maine.
The approaching system Sunday attempts to drape a front across
the International Border, which may also guide the next pieces
of the puzzle for precip into mid-week. What begins as a clipper
system across the northern tier of states early this week, will
slow as it nears the Great Lakes. Hints of a strengthening jet
across the central CONUS would help deepen the low as it moves
east, also increasing its influence on southerly moisture
advection along the East Coast. Currently these ingredients come
together too late for a more impactful system to the New
England coast, but any change in track timing or how these parts
become a whole could bring more notable QPF to the area for
early next week.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Short Term...VFR conditions will continue tonight through
Thursday before ceilings lower to MVFR on Thursday night and
widespread SHRA moves in. LLWS is expected tonight across all
terminals between roughly 06-12Z as a weak cold front crosses.
Long Term...IFR conditions should improve to VFR Friday
afternoon as RASN tapers towards and off the coast. Southerly to
southwesterly winds will be gusty, up to 30 to 40 kts at times
as a front passes through Friday morning. These higher gusts
should be short duration, slackening and becoming NW through Fri
afternoon and evening.
&&
.MARINE...
Short Term...Southwesterly winds up to 30 kts will continue
through early Thursday morning with seas of 4-7 ft across the
outer waters. Winds will then largely remain below 25 kts later
Thursday and Thursday night before increasing again early Friday
morning ahead of a cold front.
Long Term...Low pressure with a cold front will pass over the
waters Friday. This will bring a wind shift from S to NW through
the day. Gusts to gale force are increasingly likely during the
day, but SCA will be needed into the evening and overnight
hours.
&&
.CLIMATE...
Well above normal temperatures are expected this week with near-record
to record temperatures expected today into Friday.
Below are the record high temperatures for Today:
Portland, ME: 51F in 1967
Augusta, ME: 50F in 1953
Concord, NH: 58F in 1870 and 1882
Below are the record high temperatures for
Thursday.
Portland, ME: 51F in 1981
Augusta, ME: 53F in 2006
Concord, NH: 59F in 2006
Thursday Min Max:
Portland, ME: 39F in 1984
Augusta, ME: 37F in 1984
Concord, NH: 40F in 1984
Friday:
Portland, ME: 58F in 1981
Augusta, ME: 57F in 1981
Concord, NH: 59F in 2022
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...Wind Advisory until noon EST Thursday for MEZ007>009-012.
NH...Wind Advisory until noon EST Thursday for NHZ002>004.
MARINE...Small Craft Advisory until 10 AM EST Thursday for ANZ150>152-
154.
Small Craft Advisory until 3 AM EST Thursday for ANZ153.
&&
$$
NEAR TERM...Clair
SHORT TERM...Tubbs
LONG TERM...Cornwell
Area Forecast Discussion...UPDATED
National Weather Service Memphis TN
556 PM CST Wed Feb 15 2023
...New AVIATION...
.SYNOPSIS...
Issued at 313 PM CST Wed Feb 15 2023
A nocturnal severe weather outbreak is setting up over the Mid
South this evening. Showers and storms will develop later on this
evening and last through Thursday morning. This will be a long
duration severe event with the possibility of multiple waves of
storms. Dry and cooler conditions return Friday as surface high
pressure shifts across the area. Expect some sub freezing morning
lows Friday and through the weekend. High temperatures will trend
warmer through the weekend, back to near 60 by Sunday and in the
70s early next week. Warm conditions are expected to continue into
next week as showers and thunderstorms return to the forecast.
&&
.DISCUSSION...
(This evening through next Tuesday)
Issued at 313 PM CST Wed Feb 15 2023
A long duration severe weather outbreak looks poised to occur
tonight into Thursday for the Mid South. Now is the time to prepare
for adverse weather. Nighttime severe weather can be particularly
dangerous. All the ingredients are in place shear, moisture,
instability, and lift will all be in place over the region for an
extended period of time. Dewpoints across the region range from
the mid 60s across north MS to the upper 50s and lower 60s across
E AR and W TN. Dewpoints should continue to surge into the region
ahead of the front tonight. Temperatures will remain mild and
winds will remain elevated keeping the area prime for storm
development. Shear will not be an issue either as we will be in a
favorable position under a jet streak as well as 0-3 KM SRH
values will be anywhere between 300-500 m2/s2 over the region
tonight. We have been capped for the most part today, and that is
why we have been mostly quiet on the radar. Looking at the current
vis sat there is a large area of cloud streaks across the Lower
Mississippi Valley. This is indicative of horizontal shear and
the atmosphere starting to uncap and destabilize. Latest guidance
suggests that we could have between 1000-2000 J/KG of CAPE over
the Mid South tonight...this is concerning as this event we should
have the instability in place. This has been the missing link
over the last few systems. With all of that being said the Storm
Prediction Center has a large portion of the forecast area in an
Enhanced Risk of Severe weather tonight. All modes of severe
weather will be on the table. Tornadoes will be possible...some of
those tornadoes could be strong meaning EF2 or better. I am
concerned with this aspect of the threat. Large hail and damaging
winds will be possible.
Storm mode will also be important as this event should start out
as supercells, and possibly congealing into a QLCS or cluster of
storms. The supercells pose the greatest threat for the stronger
tornadoes early in the event. The best time for that is from 7PM
tonight through about 2AM tonight. The mode should congeal to a
large area of storms and tornadoes could be embedded in that, but
the heavy rain and damaging wind threat then increases during that
timeframe. Rainfall totals through tomorrow should mostly stay
just under 2 inches, but any locally higher amounts could result
in localized flooding issues. The WPC has included most of the
Midsouth in a marginal risk for Excessive Rainfall for tonight.
Portions of northeast MS and west TN near the TN river are also
included in a Slight Risk for Day 2.
The severe threat continues into Thursday as the front finally
starts to really push through the region. Storms should develop
along the front again on Thursday. Strong to severe storms will
continue and may redevelop especially across NE Mississippi. This
would be the reason why the enhanced risk remains in the area
through Thursday. Storms should be completely out of the region
by Thursday afternoon. Needless to say this is a formidable system
and everyone should stay weather aware overnight and Thursday.
Cooler and dry air will filter across the Midsouth Friday and
remain in place through the weekend. Some sub-freezing
temperatures are expected Friday, Saturday and Sunday mornings.
Highs will trend warmer; from the 40s on Friday, to the 50s on
Saturday and near 60 by Sunday.
Warm conditions are expected early next week but showers and maybe
a few thunderstorms are expected to return to the area.
&&
.AVIATION...
(00Z TAFS)
Issued at 543 PM CST Wed Feb 15 2023
Primary aviation concern remains timing of TSRA this evening.
Expect TSRA initialization to occur ahead of a secondary warm
frontal surge. CAMs are fairly close on timing and location, but
begin to diverge after 06z, when focusing features become more
nebulous. May see the bulk of TSRA north of MEM after 07Z, with
the warm front well north of the terminal. For the 00Z MEM TAF,
confidence in this scenario is too low to forgo a continuation of
VCTS through the night.
Expect another TSRA peak in the late morning/early afternoon,
with the passage of surface cold front. HRRR depicts a broken to
solid line of TSRA, with maximum intensity at TUP during the
afternoon.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
PUBLIC FORECAST...MJH
AVIATION...PWB
Area Forecast Discussion
National Weather Service New York NY
928 PM EST Wed Feb 15 2023
.SYNOPSIS...
Low pressure moves across eastern Canada as high pressure
remains off the southeast coast tonight. Another warm front
will lift into the area late Thursday into Thursday night,
followed by a cold frontal passage Friday afternoon. High
pressure will then build in through the weekend, with another
frontal system passing to the north on Monday. A series of
frontal systems then look to impact the area through much of
next week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Forecast remains on track with only minor adjustments to reflect
the most recent observations and trends of temperatures into the
overnight.
High clouds will move across the region, mainly along the coast,
from time to time through the overnight as clouds advance from
the next frontal wave moving out of Texas and the southern
plains. It will remain mild tonight, with low temps in the
lower 50s in NYC and in the 40s elsewhere.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY/...
For Thursday a deep layer W to WSW flow will be in place
initially, with increasing high clouds. Clouds with an advancing
shortwave trough and sfc warm front sold lower and thicken
rapidly in the afternoon, with showers becoming likely beginning
mid afternoon in the NYC metro area and NE NJ, then the rest of
the area around or shortly after sunset as winds also turn
southerly. Another mild day expected, with more widespread 60s
away from south facing shores, possibly lower 70s again in NJ
depending on how quickly cloud cover advances in the late
morning and afternoon.
S-SW flow should become gusty again Thu night near the coast
after passage of another warm front, especially after midnight
with the approach of a low level jet. Showers are most likely in
the evening across SE CT and ern Long Island, otherwise
becoming more widely scattered with the warm front lifting thru.
More showers expected with the approach passage of a cold front
on Friday, with a brisk W-NW flow developing after fropa with
gusts as high as 30-35 mph in the afternoon and late day. High
temps in the mid/upper 50s likely to be reached just before
fropa in the late morning or early afternoon, then falling to
near 50 in NYC and into the 40s elsewhere by sunset.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
The extended forecast looks to be dominated by generally zonal
mid- level flow with several progressive systems impacting the
area into next week.
Behind the strong cold front that moves through Friday night, a
surface high pressure gradually builds into the area and slides
off the Atlantic Coast through the weekend. While it will be
dry, much of Friday night and Saturday will be fairly gusty
under a NW flow allowing for a decent shot of cold air
advection. Lows Friday night will drop into the 20s everywhere
with teens possible inland. Highs on Saturday will be in the low
40s, much more seasonable than as of late.
As the high pressure slides offshore into Sunday, a return
southerly flow sets up allowing warmer temperatures and more low
level moisture back into the area. Highs on Sunday will be
above average, generally in the upper 40s and low 50s. A large
low pressure system over southern Canada swings through the
Great Lakes eventually pushing a cold front through the area on
Monday night. With ample moisture ahead of this cold front,
there may be a chance of showers during the day on Monday,
especially for eastern areas and along the coast.
Models then diverge in their respective solutions through the
middle to end of next week. All seem to have a series of mid-
level disturbances pushing through in the late Tuesday to
Thursday timeframe. Depending on the exact track and intensity
of each of these systems will depend on the precipitation type,
but its worth noting that with a lack of a high pressure to the
north of the area and a progressive pattern, there won`t be much
cold air that stays in place for too long. The general
precipitation type will be rain with a better chance at seeing
frozen precipitation later in the week.
Temperatures next week look to be generally above average with
highs each day in the middle 40s to lower 50s.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
High pressure remains off the southeastern coast through
tonight. A warm front moves through the region during Thursday
as low pressure approaches from the southwest. The low moves
over the the area Thursday evening.
VFR until mid to late Thursday afternoon. Around or shortly
after 20Z conditions lower to MVFR, with IFR possible at a few
locations, as rain develops.
Southerly winds around 10kt diminish through late this evening
and into the overnight, becoming westerly late tonight. Outside
of the NYC terminals winds will become light and variable. A
strong low level jet this evening and overnight will result in a
period of LLWS for all the terminals.
Winds become southerly Thursday afternoon with LLWS developing
after 20z.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
LLWS may end earlier than forecast late tonight.
No unscheduled amendments expected until Thursday afternoon
with lowering conditions as rain develops.
OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...
Thursday night...MVFR with IFR at times, and LIFR possible along
the coast, in rain showers. LLWS, ending late at night.
Friday...Rain showers likely especially in the morning with
MVFR or lower cond in the morning, gradually improving in the
afternoon. SW winds 15-20G25-30kt, becoming NW 20G30kt kt late
in the day, then slowly diminishing late at night.
Saturday...VFR. NW winds 10-15kt, becoming W in the afternoon, then
diminishing at night.
Sunday...VFR.
Monday...Chance of light rain with MVFR conditions possible.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
SCA remains in effect for the ocean waters with winds gusting to
near 25 kt across the outer waters, and ocean seas 5-6 feet.
These seas should linger into mid morning E of Moriches Inlet.
Gale Watch remains in effect for the ocean waters for late Thu
eve into Fri morning. Winds shift to the S Thu afternoon, with
SCA conditions quickly ramping to gales there late Thu night
into early Fri morning, with SCA cond likely on the south shore
and eastern bays of Long Island as well. There is some question
as to how much strong winds aloft will make it to the the
surface due to presence of a strong low level inversion...the
12Z and 18Z runs of the HRRR have both suggested potential for
gale force gusts to occur via mechanical turbulence as opposed
to convective mixing, which may be more isolated/brief in
nature.
For the first half of Friday a cold front swings through and
the winds shift to the W, then later in the day to the NW. SCA
conditions will develop on all waters daytime Friday.
SCA conditions with gusts to 25 kt on all waters Friday night
subside late night and into Saturday morning. SCA conditions
likely continue on the ocean through Saturday for elevated seas
but fall below 5 feet by Saturday night. Sub-SCA then likely for
all waters on Sunday through the beginning of Monday.
&&
.HYDROLOGY...
No hydrologic concerns are anticipated at this time through the
forecast period.
&&
.CLIMATE...
The following are daily high record temperatures for Thu Feb
16. Currently the forecast reflects that the records may be
reached at some of our climate sites, especially on Thu:
Daily Record High Temps for Thu Feb 16
----------------------------------------------
Central Park........71 (1954)
LaGuardia...........69 (1954)
Kennedy.............61 (1976)
Islip...............59 (2018)
Newark..............74 (1954)
Bridgeport..........57 (2018)
Daily Record High Minimum Temps for Thu Feb 16
----------------------------------------------
Central Park........44 (2002)
LaGuardia...........45 (2002)
Kennedy.............44 (1984)
Islip...............41 (1984)
Newark..............46 (1984)
Bridgeport..........42 (1984)
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 10 AM EST Thursday for ANZ350.
Gale Watch from Thursday evening through Friday afternoon for
ANZ350-353-355.
Small Craft Advisory until 7 AM EST Thursday for ANZ353.
Small Craft Advisory until 4 AM EST Thursday for ANZ355.
&&
$$
SYNOPSIS...BG
NEAR TERM...BG/MET
SHORT TERM...BG
LONG TERM...MW
AVIATION...MET
MARINE...BG/MET/MW
HYDROLOGY...BG/MW
CLIMATE...
Area Forecast Discussion
National Weather Service Paducah KY
458 PM CST Wed Feb 15 2023
.SHORT TERM...(Tonight through Thursday night)
Issued at 251 PM CST Wed Feb 15 2023
Severe storms remain a possibility tonight into Thursday, but
considerable uncertainty remains.
A strong surge of moisture will bring widespread showers and
storms northward through the region beginning after 9 PM this
evening and continuing into the overnight hours. The initial
storms will be elevated and according to NAM soundings should have
decent mid-level lapse rates to support a hail threat. The shear
is hard to quantify given the elevated nature of the storms, but a
few rotating updrafts cannot be ruled out. Given the widespread
convection and very meager elevated instability, the hail threat
is most likely with the initial storms and then the convection is
likely to mush out as the coverage of convection increases.
In the wake of this initial surge of convection, confidence in
the state of the environment is still quite low. Based on the 12Z
HREF, our best combination of surface-based convection and strong
shear will be from the Bootheel through the Purchase Area in the
09Z-12Z time frame. This is the most likely time and location to
see a few tornadoes or some damaging winds. Once again confidence
in any storms developing at that time is low.
After daybreak the 0-1km SRH decreases and eventually even the
0-3km SRH becomes marginal for rotating updrafts ahead of the cold
front. The thermal profiles are also uncertain, but the column
should be cooler aloft which would increase the potential for
some surface-based instability to develop, if the low clouds break
or scatter out ahead of the front. Guidance seems to be slowing
down some with the cold frontal timing, and per the latest HRRR
the best chance for redevelopment on or just ahead of the front
will be from 10 AM to 2 PM in west Kentucky. Of course, the likely
best environment will be in far eastern portions of the region
which will have the most time to warm up. An isolated strong to
severe storm with damaging winds and hail will be possible.
Storm total QPF ranges from a quarter inch in the far west and
northwest to around one and a quarter inches in the far southeast.
There is some potential for convection to train across our far
southeast counties near the Tennessee border overnight into
Thursday morning. This is most likely to occur in Tennessee, but
we will have to watch the potential for heavier rain and flood
potential near the Tennessee border.
As for temperatures, tonight will be very mild, especially in the
southeast where some locations may not drop below 60 degrees. High
temperatures Thursday will be dependent on the coverage of
convection, clouds, and frontal timing, but it will be mild with
more 70s possible in the southeast. Strong cold advection is
expected late Thursday into Thursday night and that will take lows
down in the 25 to 30 degree range from northwest to southeast
across the region.
.LONG TERM...(Friday through Wednesday)
Issued at 251 PM CST Wed Feb 15 2023
On Friday, the axis of a surface ridge will extend from Texas
through Missouri into the Great Lakes region. The ridge axis will
move across the PAH forecast area Friday evening, pushing east of
our region late Friday night into Saturday. Our area will remain
under the influence of chilly north to northwest flow Friday, which
will keep afternoon high temperatures around 10 degrees below normal
in the upper 30s to lower 40s. Clouds will decrease through the day
Friday, with clear skies expected Friday night. Winds will shift to
the south by late Friday night, but temperatures will still be a few
degrees below normal in the middle to upper 20s.
The return of southerly flow will result in a warming trend through
the weekend, with highs in Saturday already slightly above normal
readings in the upper 40s to around 50 degrees, and in the middle
50s Sunday. Lows Saturday night will be near to a little above the
freezing mark, and lows Sunday night will only drop into the middle
30s to lower 40s. With the southerly flow we will also see
increasing low level moisture, with dew points going from the lower
20s Saturday morning, to the upper 30s to lower 40s Sunday night.
Models show a surface low over the northern Great Lakes region at
00z Monday, with a cold front extending from the low to just
northwest of the PAH forecast area. This will tighten up the
pressure gradient and give us some gusts in the 25-30kt range Sunday
afternoon. The front will move into our area Sunday night into
Monday. There are some model differences in the timing of the front
and associated rain development. The model blend currently gives
our area slight to low chance PoPs Monday, with the best PoPs across
our eastern counties, with chances slowly increasing through
Wednesday as the front hangs up across or just south of the PAH
fa. There is a fair amount of uncertainty in just where the
front settles and when pulses of energy move along it, so PoPs
will be kept in the chance category or lower for now. Where the
front sets up camp will also have influence on temperatures, but
in any case, readings should remain above normal through the
period.
&&
.AVIATION...
Issued at 455 PM CST Wed Feb 15 2023
VFR conditions expected to start this TAF issuance; however, lower
ceilings and visibilities will arrive toward 06Z/16 as a warm
front lifts through the area. The best chance for seeing more
widespread thunderstorm activity will be at the PAH/OWB/EVV TAF
sites, where some severe thunderstorm activity will be possible as
well. The main threat will be hail early in the overnight hour and
then transition to a wind threat late in the night and early
Thursday as a cold front arrives. Expect some gusty winds to
around or just over 20kts ahead of the cold front. Improving
conditions can be expected Thursday afternoon.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
SHORT TERM...DRS
LONG TERM...RST
AVIATION...KC