Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/02/23
AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
1049 PM EST Wed Feb 1 2023
.SYNOPSIS...
The pattern will remain unsettled into early Friday as another
weak wave of low pressure brings the chance for additional
precipitation to the local area. A strong area of arctic high
pressure will build south for Friday into the start of the
upcoming weekend, bringing cold but dry conditions. Milder
weather begins Sunday and continues through the middle of next
week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
As of 1020 PM EST Wednesday...
The latest analysis indicates ~1028mb sfc high pressure centered
across the Delmarva into east/central VA with low pressure to SW
of the local area. Aloft, W-SW flow continues in between a sub
tropical ridge over the central and eastern Gulf of Mexico, and
a broad upper trough over the northern tier of the CONUS. A lot
of high clouds continue to stream through the region, but have
been transparent enough to allow temperatures into the mid-upper
20s across the eastern shore and into areas N of I-74 and E of
I-95. Farther S and W, the cloud cover is a little thicker with
temperatures mainly 30-35F. Expect dry conditions through
sunrise for about the northern 2/3 of the CWA, with some light
overrunning precip expected to move into south central and SE VA
and NE NC after about 3 or 4am. Areas that see precip will genly
be around freezing but the precip will be fairly light. BUFKIT
soundings show most of the column below freezing, with a narrow
elevated warm layer aloft into NC and far southern VA through
12Z. Expect a brief period of wintry mix with this setup (either
mostly likely sleet/rain in NC and snow/sleet into south
central/interior SE VA). The 00Z HRRR is a little more
aggressive at bringing QPF north into the area so raised PoPs
after 09Z a little but still am not expected any accumulation
and fairly minimal QPF amounts. If this over-performs, the
piedmont of south central VA appears to have the highest chc for
seeing a light coating on grassy surfaces w/ a few hrs of light
snow and sleet (though this is low confidence and would be a
narrow zone). Overnight lows in the lower- mid 20s ern shore,
25-30F central VA, with upper 20s/lower 30s for south central
and interior SE VA (mid 30s at the coast in SE VA/NE NC).
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
As of 330 PM EST Wednesday...
Overall, models are a bit more suppressed with the majority of
precipitation tomorrow, and have confined high end chance to
likely pops mainly over the southern third of the area. Farther
north, some light precipitation will move in from mid to late
morning. Again, antecedent dry airmass may lead to a short
period of wintry mixed ptype due to wet-bulbing effects along
and south of I-64. Sfc temperatures will also begin to rise
sufficiently above freezing as the pcpn arrives. No significant
wintry precipitation is expected, with a changeover to all rain
in all areas by late morning/midday Thu. PoPs begin to ramp
down across central VA and northern neck/middle peninsula areas
by early afternoon, though a second round of overrunning
precipitation across the Carolinas will keep chance to Likely
PoPs over SE VA and NE NC through Thu evening. Highs Thu in the
l-m40s N and NW and m-u40s S and SE.
Gradual lowering of PoPs over the northern OBX into Friday
morning, with some partial clearing is possible after midnight
NW. Lows from the u20s-l30s N and NW to the m-u30s SE.
Rain will be ending across far SE zones at sunrise Friday
morning, as sfc low pressure slides across coastal GA/SC.
Meanwhile, a strong cold front will be dropping across the
northern Mid-Atlantic into our northern zones through Fri
morning, as strong 1040+mb Canadian high pressure builds from
the northern Plains into the Ohio Valley/interior northeast Fri
morning into Fri aftn. Sky clears out with NNW winds increasing
and becoming gusty/windy along the coast, with falling
temperatures from early to mid aftn as thicknesses rapidly fall
into Friday night. Highs Fri from the u30s-l40s N to the m40s S.
Colder Fri night as N winds continue to (briefly) usher in the
coldest air across our region since Christmas week. Mainly clear
Fri night w/ possible exception for BKN SC INVOF along coastal
SE VA- NE NC. Lows in the low to mid teens well inland...l-m20s
from Hampton Roads to coastal NE NC. Modifying Canadian high
pres will be situated over/just N of the local area on Sat.
Sunny- partly cloudy, breezy and cold w/ highs no better than
the u20s-l30s across the north, m30s far S and SE. Starting out
Sat morning w/ wind chills from the single digits to lower
teens...then no higher than the teens to l20s in the afternoon.
Another cold night Sat night w/ lows in the upper teens to mid
20s...m-u20s along coastal SE VA-NE NC.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 330 PM EST Wednesday...
Transient high pressure will be shifting offshore Sat night, which
will lead to quickly rebounding temps (especially compared to
daytime Sat) for Sun and into the middle of next week. However,
with relatively light winds and mainly clear skies, one more
very cold morning expected Sun. Lows in the 20s areawide
(including at the coast), with even some teens possible in
interior S/SE VA where there is the greatest chance for
decoupling. Highs Sun range from the low 50s across the NW and
MD Eastern Shore to the upper 50s/around 60 in SE VA and NE NC.
A weak upper-level trough w/ several embedded shortwaves will
approach the area early next week. A southern stream shortwave
could spark weak cyclogenesis off the Carolina coast Mon, with
light showers possibly encroaching on our far SE areas (mainly
OBX Currituck and points SE). The GFS is slightly more amplified
and has greater precip coverage compared to the ECMWF. Either
way, any precip would remain light. As a result, will only be
carrying slight chc PoPs for Hampton Roads and NE NC. Highs Mon
remain a couple degrees above normal (mid to upper 50s). Lows
Mon night near normal (29-32 inland with mid/upper 30s at the
coast).
Modifying high pressure builds in over the eastern CONUS by
Tuesday with low-level SW flow increasing. Highs Tues in the
upper 50s to low 60s. Lows Tues night remain on the mild side,
in the 40s. For Wed, differences remain but generally will side
with blended guidance for temps given uncertainty. This leads to
mild highs in the mid to upper 60s and lows in the 40s. Towards
the middle/end of next week, high pressure moves further
offshore as trough digs over the midwest and brings the next
chance of unsettled wx to the region. However, significant
differences remain among the global guidance so PoPs generally
remain aob 30% through the end of the extended period.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
As of 700 PM EST Wednesday...
VFR conditions prevail at the main terminals, with some MVFR
conditions across the piedmont where some lower clouds persist.
Dry into the early AM hours Thu, but expect some light precip
to spread in from the W/SW from 08-12Z, with the highest chances
across south central VA and NE NC (will have some -RA starting
at ECG prior to 12Z). IFR ceilings are expected and ECG (and
possibly ORF) by Thursday afternoon, with mainly MVFR or low-end
VFR CIGs for RIC/PHF (probably staying VFR at SBY). VFR
conditions return to RIC by Thu night, with lingering MVFR or
IFR conditions near the coast in SE VA and NE NC.
Outlook: Drier and VFR conditions Friday as a strong cold front
moves through the region...to be followed by strong hi pressure
building in from the NNW Sat. Breezy to locally windy Fri into
Sat (esp along the coast).
&&
.MARINE...
As of 330 PM EST Wednesday...
Latest sfc analysis shows a cold front draped from W to E across SC
and high pressure building in to the NW. Latest obs show N-NNW winds
are 15-20kt with gusts to 25kt. A few sites in the mouth of the bay
are gusting closer to 30kt. Winds in the upper bay have already come
down to sub-SCA levels. Expect that all zones will have Sub-SCA
winds later this evening. Waves in the Bay/Rivers are 1-3ft, seas
north of Cape Charles are 3-5ft, and seas south of Cape Charles are
5-7ft. Going to let the SCAs in the 2 northern Bay and the Lower
James River zones expire at 4pm, but will extend the SCAs for the
lower Bay, mouth of the Bay, and the coastal waters from Cape
Charles to Parramore Island to 10pm. The two southern coastal water
zones will also expire at 10pm.
With high pressure overhead Thursday/Thursday night, conditions will
be benign. Expect variable winds at or less than 10kt. High pressure
then slides offshore going into Friday morning as a cold front drops
into the local area through the day Friday. The strong CAA and
tighter pressure gradient will lead to widespread SCA conditions on
Friday. NNW winds will be ~25kt with gust to 30kt. Waves will
generally be 2-4ft, but could see some 5ft waves in the mouth of the
Bay. Seas will be 5-6ft. Given the elevated winds and cold
temperatures Friday night, there is the possibility of freezing
spray, especially in the northern coastal waters and northern Bay.
Winds will come down Saturday as cold high pressure builds in
overhead. Do expect winds to pick back up to 10-20kt out of the SW
once the high pressure pushes offshore Sunday, but not expecting
winds or waves/seas to reach SCA conditions at this time.
&&
.CLIMATE...
As of 900 PM EST Tuesday...
January 2023 has been a warm month, with average temperatures
ranging from around 6 degrees above normal across southern
portions of the forecast area to 8 degrees above normal for the
north. For our 4 primary long-term climate sites, preliminary
monthly temperature and rankings are listed below:
Jan 2023 Average Temperature (preliminary)
* RIC: 46.2 (6th warmest on record, warmest 49.7 in 1950).
* ORF: 47.8 (11th warmest on record, warmest 53.3 in 1950).
* SBY: 44.7 (4th warmest on record, warmest 48.0 in 1950).
* ECG: 48.7 (8th warmest on record, warmest 55.9 in 1937).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.
&&
$$
SYNOPSIS...MAM
NEAR TERM...LKB/MAM
SHORT TERM...MAM
LONG TERM...SW
AVIATION...LKB/MAM
MARINE...AM
CLIMATE...AKQ
Area Forecast Discussion
National Weather Service Goodland KS
435 PM MST Wed Feb 1 2023
.SHORT TERM...(This evening through Friday night)
Issued at 229 PM MST Wed Feb 1 2023
At the beginning of the short term period, the latest RAP analysis
shows the CWA just west of a converging jetstream with an upper air
ridge over the Pacific Northwest and and upper air cutoff low just
south of AZ. Current satellite imagery and surface observations show
dry conditions across the region with the CWA still having a good
amount snow cover at the surface as well clear skies though a few
clouds are seen moving in a northeastern track across the area
from Leoti to Hill City in KS. Forecast models show the upper air
ridge gradually moving eastward to cover more of the western CONUS
as the cutoff low opens into a wave as it travels into NM. At the
surface, mostly cloudless skies allow for daytime temperatures to
top off in the lower to middle 30s with virtually zero chances
for precipitation. Winds expect to be generally west-northwesterly
through the day going into the night around 5-10 kts. As the
clear skies continue overnight, tonight`s lows look to drop
between the middle single digits and the lower teens with minimum
wind chills ranging from zero to around 5 below zero.
On Thursday, models show the front part of the upper air ridge
advancing over CWA by the evening yielding a mostly northerly flow
through the latter half of the day. At the surface, dry conditions
are expected once again throughout the day. A surface high is seen
over ND during the middle of the day causing a tight pressure
gradient across the CWA yielding some breezy northerly winds in the
afternoon. Daytime highs for Thursday warm a bit to between the
middle 30s and lower 40s with overnight lows in the upper single
digits to middle teens. Models show the potential for some patchy
fog developing around midnight and going into the following day in
areas along and east of KS-25, so it was added to the forecast in
collaboration with neighboring offices. Not enough confidence for
a Dense Fog Advisory now, but will monitor in case this changes.
For Friday, forecast guidance depicts the upper air ridge continuing
its eastward progress through the day with the axis of the ridge
passing over the CWA during the night. Models also show a warm front
passing through the CWA during the day with an 850mb temperatures
reaching up to around 8 to 10 degrees Celsius. After the morning
clouds dissipate in the eastern half of the CWA, daytime highs for
Friday look to warm up to lower to middle 40s. Cloud cover looks to
increase going into the night while the region sees overnight
lows in the lower to middle 20s.
.LONG TERM...(Saturday through Wednesday)
Issued at 200 PM MST Wed Feb 1 2023
Shortwave trough moves through to start the period with no
precipitation but breezy to windy conditions. Models currently
indicating gusts in the 35-45 mph range possible through Saturday
afternoon with northwest winds behind the cold front. Front has
little impact on temperatures with highs both Saturday and Sunday
in the 40s and 50s. For the first part of next week, models really
staring to diverge on the upper pattern. Does appear to be a
broad southwesterly flow early in the week as a trough digs into
the Four Corners. The evolution of that system for mid to late
week is in question. The GFS closes off a strong upper low and
ejects into the central plains which would result in snow and wind
towards Wednesday. However, the ECMWF keeps it an open wave which
moves across the southern plains with little to no precipitation
further north. Until those differences are resolved confidence is
rather low in the latter half of the forecast period. Generally
speaking, temperatures will start out mild with highs mainly in
the 40s, then gradually cooling towards the end of the period,
however do not see any Arctic air returning. Blended forecast
yields some low POPs Monday night for rain/snow, closest to the
ECMWF solution, but that probably should be taken with a grain of
salt given the vast differences in the models.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 435 PM MST Wed Feb 1 2023
VFR conditions forecast at both airports through 00z tomorrow
evening. Light winds forecast throughout the TAF period with southwest
being the prevailing direction. A backdoor cold front looks to
move in from the northeast tomorrow evening, bringing a chance for
fog and stratus overnight, which may impact the KMCK TAF. Put in a
FEW025 group to reflect the potential for stratus moving in late
in the TAF period, though think any impactful aviation concerns
will fall after the 00z end for the TAF period.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...076
LONG TERM...024
AVIATION...RRH
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1040 PM EST Wed Feb 1 2023
.UPDATE...
Issued at 1040 PM EST WED FEB 1 2023
A review of radar trends and the CAMs consensus suggests that the
threat for a wintry mix of weather is just a bit further south
than it looked this afternoon. Accordingly, have tweaked the
ongoing SPS to drop some of the northern counties from Rockcastle
to Breathitt. With this update have refined the PoPs and QPF along
with adding in the latest obs and trends for the T/Td/Sky grids.
These updates have been sent to the NDFD and web servers with a
freshening of the zones and SAFs to follow shortly.
UPDATE Issued at 645 PM EST WED FEB 1 2023
23Z sfc analysis shows the wavy frontal boundary separating the
cold from the milder air is just to the southeast of the state.
This boundary will continue to serve as a lifting mechanism for
the next wave of moisture affecting southern parts of eastern
Kentucky tonight into Thursday morning. Currently, temperatures
vary from the upper 20s north to the mid 30s in the far southeast.
Meanwhile, amid light and variable winds, dewpoints range from
the mid 20s northwest to the low 30s in the southeast. Low clouds
cover most of the area as the next round of light pcpn is poised
to move into the Cumberland Valley from the southwest. Have
updated the forecast to put more focus on the southern threat of
mixed pcpn with this incoming wave. The latest HRRR and other high
resolution models keep the measurable pcpn just to our southern
tier. Accordingly, have lowered PoPs and QPF for the next northern
tier of counties overnight. The SPS for this area continues to
highlight the small threat for light icing. With this update,
have also added in the current obs and trends for the T/Td/Sky
grids. These updates have been sent to the NDFD and web servers
along with forthcoming freshening of the SAFs and zones.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 326 PM EST WED FEB 1 2023
Key Messages:
1. Wintry mix returns to Eastern Kentucky tonight through Thursday
morning.
2. Colder air moves into the region for the end of the period.
Analysis and Discussion:
High pressure sitting over the central CONUS is in place; however, a
surface low moving off the eastern seaboard with a stationary
boundary extending across the Deep South has kept cloud cover across
the region. A few breaks in the clouds along the I-64 corridor exist
and as a result; temperatures have climbed into the low-30s.
Everywhere else, cloud cover has remained in place and with the help
from lingering accumulated ice and snow; temperatures haven`t really
warm out of the 20s. Aloft, a weak jet max moving through low
levels will favor surface cyclogenesis across the Deep South. Also,
an existing baroclinic zone will favor development of the low. As
the low tracks along the boundary, the deformation zone will cross
through portions of southeastern Kentucky. With cold air in place
from last night`s system, very little diurnal warming taking place
and a wintry mix favorable sounding, opted to put instances of
wintry mix across those area. An SPS extending on a line from
Rockcastle County to Pike County and southeast toward the TN/VA
border was issued to reflect the minor impacts of the ice. Overall
accumulations of ice and snow are minimal but enough to cause
potential issues tonight.
Further to the north but within the same longwave trough; a strong
jetstreak and associated closed H5 circulation exists and will bring
the next impact to Eastern Kentucky. As that vertically stacked
circulation tracks to the east into New England, the surface cold
front is forecast to extend across the CONUS. This cold front will
track toward the forecast area through the day Thursday before
crossing late Thursday. The moisture starved front won`t provide
much in the way of PoP aside from a few snow flurries across the
eastern coalfields; however, overnight lows for Thursday will be
colder then average. Overnight lows in the upper-teens to lower-20s
is expected. Flurries will continue into the long-term but high
pressure will establish itself across the region thus bringing and
end to an active period.
.LONG TERM...(Friday through Wednesday)
Issued at 400 PM EST WED FEB 1 2023
Key Messages:
* A stretch of dry weather is expected through Monday night.
* A cold, rather dry airmass moves in for Friday and Friday night.
Precipitation chances return by late Tuesday.
* Humidity is expected to bottom out below 25 percent on Saturday
and moderate 5 to 10 mph winds from the southeast to south with a
downslope component will likely dry out fine fuels.
* Temperatures modify to well above normal late this weekend and
into next week.
The period is expected to begin with an upper level low centered
in Quebec with an upper level trough extending into the Mid
Atlantic coast to the Lower MS Valley. Further west a shortwave
ridge is expected to extend from Northern Mexico into the Rockies.
West of this, a shortwave trough is expected to be nearing the
west Coast of the Conus with additional upstream shortwaves over
the eastern Pacific gradually approaching the west coast of the
Conus. Meanwhile as the period starts, a ridge of sfc high
pressure is expected to extended from the Upper MS Valley south
to the Southern Plains. At that point a shortwave trough is
expected to be working into the Appalachians. A surface frontal
zone is progged to be sagging south across the Central to Southern
Appalachians to Lower OH Valley to Plains and may bisect the CWA
at dawn on Friday. Futher west an area of lower sfc pressure is
expected to extend from Alberta to the western Dakotas to High
Plains.
Friday to Saturday night, the pattern is expected more or less
takes on a bit of zonal character from the Rockies to the eastern
Conus. The upper level low is expected to work from Quebec to the
St Lawrence Valley to the Maritimes with the axis of the upper
level trough shifting off the eastern seaboard. At the same time,
the initial shortwave trough will move east of the area on Friday
morning. Some low clouds that extend into the DGZ are anticipated
as the period begins and this combined with the sagging cold
front could lead to isolated flurries as the period begins.
Otherwise, the shortwave upper level ridge should move into the
Plains and then to the the MS Valley to eastern Conus, the axis of
which should cross eastern KY late Saturday to Saturday evening.
A shortwave trough which will have worked into the western Conus
and across portions of the intermountain west through Friday night
will emerge into the Plains on Saturday, reaching near the MS
Valley to eastern TX line by dawn on Sunday. Sfc high pressure is
expected to build into the area on Friday and cross the area on
Friday evening, settling from Upstate NY to the mid Atlantic sates
to southeast late Friday night, before shifting off the eastern
seaboard and into the Southeast by later Saturday into Saturday
night. In advance of the shortwave trough emerging into the Plains
and nearing the MS Valley by dawn on Sunday, a sfc low is
expected to track across Southern Canada to Northern Great Lakes
with an associated warm front lifting northeast across the area
later Saturday. The pressure gradient will increase across the OH
Valley later Saturday into Saturday night between the high
shifting to the east and southeast and a sfc through/lower
pressure extending from the low to the Southern Plains/Red River
Valley.
Sunday to Monday, the shortwave trough is expected to move into the
Central Great Lakes to Lower OH Valley to Southeast on Sunday while
another shortwave trough should move across the Great Lakes to
Appalachian region Sunday night to early Monday, before ridging
shifts into the eastern Conus Monday. An upper level trough in the
rather progressive pattern is then expected to gradually work
across the north Central to Upper MS Valley to the Great Lakes to
Ontario and Quebec Monday night to Tuesday.
There is more uncertainty with the evolution and timing of
troughing moving from the Intermountain west to the Central Conus
or Southwest Conus Monday night to Tuesday night. The past couple
of GFS operational runs close off an upper level low in the
Southwest Monday night to Tuesday and only gradually move it to
the Southern Rockies and nearing the Southern Plains at the end of
the period. Further downstream, the last two GFS operational runs
bring a shortwave ridge into the OH Valley to end the period.
Meanwhile, last two ECMWF operational runs bring an initial
trough from the Intermountain west to the Central Conus on Tuesday
and into the Great Lakes to OH Valley to Appalachian region
Tuesday night to Wednesday. Yet another shortwave trough moving
into and across the western Conus into the Central Conus behind it
Monday night to Tuesday night to Wednesday with the axis of the
upper level trough west of the region generally yielding
southwest flow aloft from the Southern Plains to the OH Valley,
Appalachians and to the eastern Conus.
A cold and dry airmass will have advected into the region by the
start of the period and a rather chilly night into the teens for
most locations and well down into the lower 10s for valleys is
anticipated in the valleys for Friday night. PW with this airmass
is progged to be about 40 to 60 percent of normal for this time
of year as the period begins Friday night to Saturday. A
considerable amount of sunshine is expected for Saturday and
temperatures should moderate well into the 40s to near 50 while
dewpoints in the single digits to teens to start the day with some
moderation late. This will lead to drier humidities compared to
recent day with 25 percent min rh expected to be widespread. The
pressure gradient is expected to be stronger west and northwest of
the area, but 5 to 10 mph afternoon winds with a downslope
component from the southeast to south are anticipated. The HDWI
max from the 0Z GEFS this morning is generally above the 50th
percentile for most members. Overall, this should lead to pattern
that should dry fine fuels and leaf litter.
Winds will be a bit stronger on Sunday, more into the 10 to 15 mph
range, as the shortwave and sfc trough/weak front move across the
Commonwealth, but some southwest flow will lead to a gradual
increase in dewpoints and rh. It is conceivable that rh ends up
lower than what NBM guidance suggests. Again the HDWI from the 0Z
GEFS has several members above the 50th percentile.
No measurable precipitation is anticipated before late Tuesday
with chances lingering into Wednesday if something more along the
line of the ECMWF and ECMWF ensemble were to verify, versus the
recent GFS and GFS ensemble means.
After Friday night, temperatures climbing to above normal will
prevail through end of the balance of the long term period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
ISSUED AT 715 PM EST WED FEB 1 2023
Most of the sites will have LIFR to IFR CIGs through the first
part of the period as the latest wx system moves into the area
from the southwest. As this occurs, VCSH will be possible after
09Z Thursday for those southernmost terminals - LOZ and SME. Look
for the VCSH threat to end by late morning on Thursday with
improving CIGs into the afternoon. Winds will be light and
variable through the period.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...VORST
LONG TERM...JP
AVIATION...VORST/GREIF
Area Forecast Discussion
National Weather Service Memphis TN
854 PM CST Wed Feb 1 2023
...New UPDATE...
.UPDATE...Issued at 820 PM CST Wed Feb 1 2023
Light freezing rain continues across much of the Midsouth. The
freezing line has basically been stationary for the last 24 hours,
draped over northeast Mississippi from Iuka, to central Tallahatchie
county. Most of the Midsouth north and west of this line remains
in the upper 20s to around 30 degrees. CAA has nearly dropped out
completely tonight, but ice/sleet on the ground with a bit more
still to come will continue keep temperatures in check tonight and
tomorrow. Additionally, dense, low clouds will remain across the
Midsouth, so insolation will be minimal. Expect morning lows in
the upper 20s to low 30s across most of the region. Freezing fog
could also develop across much of the area.
Ground truth reports of freezing rain have become sparse north of
I-40 in portions of the Ice Warning and Winter Advisory areas, but
dew points depressions are around 3-4 degrees cooler than the are
farther south along I-40. As a result, there is still room for
saturation as light precipitation falls across the area.
Additionally, LZK radar shows heavier returns approaching
northeast Arkansas and west Tennessee which is in line with what
the HRRR has been forecasting. Furthermore, the NAM looks a bit
more convective by 12z suggesting heavier precip is possible. As
a result, will maintain all Warnings/Advisories for now and see
how the next several hours unfold.
It looks like we will finally see most of the Midsouth climb above
freezing after midday tomorrow. However, it still appears most
guidance is a bit on the warm side. As has been the case for the
past 48-72 hours the HRRR is on the cooler end of guidance and is
the basis of my temperatures tonight and tomorrow(minus 1-2
degrees).
Slightly warmer temperatures should result in all rain tomorrow
afternoon with dry conditions returning tomorrow night and
persisting through the weekend.
12/Sirmon
&&
.SYNOPSIS...
Issued at 304 PM CST Wed Feb 1 2023
The third round of wintry weather will occur later this afternoon
through Thursday morning. Temperatures should then slowly warm up to
where a changeover to all rain is anticipated. Rain is expected to
remain in the forecast until early Friday morning. Friday through
early next week looks to remain dry. Temperatures should rebound
into the 50s during this timeframe. Late Tuesday into Wednesday the
next system should arrive bringing some rain back to the region.
&&
.DISCUSSION...
(This evening through next Tuesday)
Issued at 304 PM CST Wed Feb 1 2023
As of 3 PM CST, looking at Satellite data we are mostly overcast
across a good portion of the Mid-South. Along the KY/TN border we
have some peeks of sun occurring and this could aid in some
sublimation of the ice we have received over the past two days.
However, temperatures should begin to cool down as the sun sets. As
for the rest of the Mid-South, an overcast sky dominates and will
continue to do so through at least tomorrow. Temperatures are in the
mid to upper 20s to near 30 degrees. Parts of northeast Mississippi
have warmed into the low to mid 30s with temperatures warming to
near 40 degrees. Now with temperatures out of the way let`s talk
about this third round of icy weather. On radar we have freezing
rain and some sleet moving along and south of I-40. Looking at
sounding data where temperatures are above freezing, some rain
and sleet is possible given the temperature profile, mostly in
northeast Mississippi.
Speaking of winter headlines. A few changes have been made. First,
to the Ice Storm Warning, Craighead to Greene Counties in AR, the MO
Bootheel and the following counties in TN: Lake, Obion, Henry,
Weakley, Dyer, Gibson, Carroll and Benton have been removed and in
place have been put into a Winter Storm Advisory with only a glaze
of ice expected. This will go through 6 AM. The Ice Storm Warning
continues through noon tomorrow with only those counties being
removed. The next Winter Weather Advisory which is in effect and
goes through 6 AM encompasses the following counties in MS:
Tallahatchie, Yalobusha, Calhoun, Pontotoc, Union, Prentiss and
Tishomingo.
Given this has been a fairly long duration event we have compounding
impacts. Most locations have received anywhere from 0.10-0.40 inches
of ice and sleet over the past 2 days. Any ice that falls tonight
may cause more tree damage and more power outages. Road conditions
are slick and icy and will most likely deteriorate though the
evening and overnight periods in Advisory and Warning areas. Please
use extreme caution if you absolute must be out on the roads.
As we move into tomorrow mid-morning, temperatures are expected
to move above freezing causing any falling precipitation to be in
the form of rain. Rain is expected to continue through early
Friday morning as this system finally exits stage left.
For the weekend, we look to dry out with plenty of sunshine. A
welcome relief for all! Temperatures are expected to be in the 50s
with some parts of northeast Mississippi reaching into the 60s by
Sunday.
Nearly zonal flow aloft over the region for the start of next week
should keep us dry. Clouds will build in as the next low pressure
moves across the Desert Southwest into the Plain states. This looks
to bring another round of rain to the Mid-South for Tuesday and
Wednesday. While this system is still a bit far out, severe
weather at this time looks unlikely. This will of course be
watched as we get closer to the event.
SMW
&&
.AVIATION...
(00Z TAFS)
Issued at 551 PM CST Wed Feb 1 2023
RA at TUP and FZRA elsewhere expected for tonight into Thursday
morning. A changeover to RA expected towards late Thursday
morning as temperatures warm above freezing. VFR to perhaps
temporary MVFR conditions at JBR, with IFR conditions prevailing
elsewhere and a gradual improvement to MVFR/VFR conditions towards
Thursday afternoon/evening. Light NNE winds through the period.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Winter Weather Advisory until 6 AM CST Thursday for ARZ009-018-
026.
Ice Storm Warning until noon CST Thursday for ARZ027-028-035-036-
048-049-058.
MO...Winter Weather Advisory until 6 AM CST Thursday for MOZ113-115.
MS...Winter Weather Advisory until 6 AM CST Thursday for MSZ006-009-
014-015-020>022.
Ice Storm Warning until noon CST Thursday for MSZ001>005-007-008-
010>013.
TN...Winter Weather Advisory until 6 AM CST Thursday for TNZ001>004-
019>022.
Ice Storm Warning until noon CST Thursday for TNZ048>055-088>092.
&&
$$
PUBLIC FORECAST...JDS
AVIATION...CJC
Area Forecast Discussion
National Weather Service Nashville TN
644 PM CST Wed Feb 1 2023
...New UPDATE...
.UPDATE...
Issued at 644 PM CST Wed Feb 1 2023
The evening sounding from OHX is much less decisive than 24 hours
ago, which distinctly favored freezing rain. Tonight, the warm
layer isn`t quite so pronounced and so sleet is just as much a
possibility as freezing rain. However, any precipitation we
receive will be light. Although there is plenty of moisture in
dendritic layer (-12C to -18C), the low-levels are noticeably
drier. At any rate, we earlier extended the Winter Weather
Advisory southward to the TN/AL state line. The HRRR does bring
light precipitation across the advisory area off-and-on throughout
the evening and overnight, and with temperatures even now at or
below freezing, there is a good chance of meeting at least low-end
advisory criteria. Otherwise, the forecast looks to be in good
shape.
&&
.SHORT TERM...
(This afternoon through Thursday)
Issued at 234 PM CST Wed Feb 1 2023
Very difficult forecast for today and tonight as models are
really struggling with the cold airmass in place and how much of
a wintry mix we will see tonight. Have had to throw out most
model guidance and base forecast for today/tonight on current obs
and forecast experience. For this afternoon into this evening,
radar is already showing precip moving into our southwest
counties ahead of schedule, while surface obs indicate a mix of
freezing rain, sleet and snow is occurring around the Memphis
area. Nearly all guidance has continued to be too warm with
temperatures today, such as the NBM which is around 5-6 degrees
too warm, with current readings still in the upper 20s in our
northwest counties and low 30s elsewhere. Forecast soundings
indicate that as precip arrives through the afternoon and evening
and falls into dry air aloft, the extreme warm nose of 5-7C
around 750mb that brought all the freezing rain the past two days
will erode to around 0-3C, coldest in our north and warmest in
the south. This will lead to thermodynamic profiles and web bulb
zero lines roughly straddling the 0C isotherm, so precip will
range from just light rain in our southeast, to light
rain/freezing rain/sleet in the middle, and light sleet or even
snow in our north. It`s also possible there could be a mixture of
all precip types in some areas due to elevation and the marginal
freezing temperatures both surface and aloft. By late tonight and
especially during the day tomorrow, temperatures are anticipated
to really truly warm above freezing, and any wintry mix will
change to all rain before it shifts out of the area during the
afternoon and evening.
With all that said, appears our west-central counties to the west
and southwest of Nashville will be where the coldest temperatures
intersect with the most QPF, which is in line with the HRRR and
HREF models. These counties have the potential to see additional
ice accumulations up to one tenth of an inch, so have gone ahead
and issued our third-day-in-a-row Winter Weather Advisory for that
area. This area also still has considerable ice on trees, power
lines and roads from last night, so any additional ice could cause
considerable impacts. It should be noted, however, that with the
forecast tonight being of low confidence, the advisory may need to
be adjusted depending on how everything evolves. It does appear
our far north will see little QPF, so even if ice or snow falls
there it will not accumulate much. Over the far south and
southeast, mainly rain is expected with no wintry impacts.
&&
.LONG TERM...
(Thursday night through next Wednesday)
Issued at 234 PM CST Wed Feb 1 2023
All precipitation will be out of the area by Thursday evening as
the main upper trough finally shifts eastward away from us. This
will give us a very welcome break for the wintry and rainy
weather, with dry conditions Friday through Monday. Friday and
Saturday look quite chilly with lows in the 20s and possibly 10s
with highs only in the 30s/40s on Friday and 40s/50s on Saturday.
Significant warmup occurs next week as another large upper trough
approaches with strong southwesterly winds aloft, with highs
warming into the 60s Sunday and Monday and possibly even the 70s
by Tuesday. Speaking of Tuesday, 12Z guidance shows the next cold
front moving into the midstate with our next chance for rain.
&&
.AVIATION...
(00Z TAFS)
Issued at 540 PM CST Wed Feb 1 2023
MVFR to IFR conditions at forecast time and these are expected to
stick around for most, if not all, of this TAF cycle. Light radar
returns are on radar, but I think the bulk of the measurable
rain/freezing rain will remain south of our mid-state terminals.
The only exception could be CSV late tonight for a few hours when
they fall to LIFR.
Winds will be light to calm with mainly a northwest fetch.
&&
.PRELIMINARY POINT TEMPS/POPS...
Nashville 31 44 27 38 / 40 40 20 0
Clarksville 28 42 23 36 / 20 20 10 0
Crossville 32 44 24 35 / 60 70 40 0
Columbia 31 41 26 38 / 70 70 30 0
Cookeville 30 43 26 36 / 50 50 20 0
Jamestown 30 43 23 33 / 40 40 20 0
Lawrenceburg 31 41 27 38 / 70 80 60 0
Murfreesboro 31 43 26 38 / 60 60 30 0
Waverly 29 41 24 36 / 30 30 10 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 9 AM CST Thursday for Cheatham-
Dickson-Giles-Hickman-Houston-Humphreys-Lawrence-Lewis-Marshall-
Maury-Perry-Wayne-Williamson.
&&
$$
UPDATE.......Rose
SHORT TERM...Shamburger
LONG TERM....Shamburger
AVIATION.....Unger
Area Forecast Discussion
National Weather Service Pocatello ID
142 PM MST Wed Feb 1 2023
.SHORT TERM...THIS AFTERNOON THROUGH THURSDAY NIGHT...
Today and Thu will be governed by a building ridge of high pressure
providing quiet, dry, low-impact wx. Temps will continue to
moderate/trend warmer, with highs today in the teens/20s warming
another 5 degrees or so tomorrow, and lows 10 degrees either side of
zero tonight. Did undercut NBM guidance for highs both days, and
lows tonight, based on verification from the past several days where
the NBM has been running too warm, with special attention across our
srn highland/Bear Lake valleys. Patchy (but not widespread) AM
freezing fog still cannot be ruled out anywhere, and we added this
to the forecast over the Arco Desert/adjacent Central Mntn valleys
as this is where the HRRR and NBM advertise the best potential. 01
.LONG TERM...FRIDAY THROUGH NEXT WEDNESDAY...
The ridge of high pressure in place over most of Idaho early
Friday will shift eastward throughout the day. This will open the
door for a weak shortwave to pass through the area Friday night
into early Saturday. This is going to be a quick hit of light
snow, mainly for the higher elevations of the Sawtooths and
Eastern Highlands. Even there, totals are expected to be light
with the NBM 4.1 showing about a 20-30% chance of at least an inch
of snow in the 24 hours leading up to 12Z Saturday and a 10-20%
chance of at least 2 inches of snow. In the valleys, any snow that
makes it to the surface will lead to little to no accumulation.
Our gradual warming trend will be continuing during this time with
highs reaching the upper 20s and low 30s for most on Friday, with
highs closer to mid 30s farther south. Highs creep up a few more
degrees on Saturday and Sunday with more of us back in the 30s and
even some low 40s. The next trough arrives in our area on Sunday
and will bring another snow chance with it. This looks to bring
measurable snow to a more widespread area with the NBM 4.1 showing
about a 20-40% chance of at least an inch of snow for the valleys
and higher totals up in the mountains. The GFS handles the
evolution, track, and strength of this Sunday system in a much
different way than the ECMWF as it (the GFS) plunges the low
farther south before moving it eastward through the southwestern
US. Regardless of specifics in tracks, both models generally agree
on the potential for snow Sunday into Monday. Models show another
wave of moisture heading our way in the middle part of the week.
AMM
&&
.AVIATION...18Z WEDNESDAY THROUGH 18Z THURSDAY...
There`s a mix of upper level clouds and clear sky out there today
as high pressure builds in over the area. Thanks to the ridge, we
can expect VFR conditions at all terminals. The one caveat coming
with it is the potential for an inversion impacting VIS beginning
around 15-16Z Thursday. Confidence in actual impacts to VIS
(dropping to MVFR) is low at this time and more likely at IDA and
PIH if this materializes. AMM
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$