Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/07/19
Area Forecast Discussion
National Weather Service La Crosse WI
530 PM CST Wed Feb 6 2019
.SHORT TERM...(This evening through Thursday)
Issued at 250 PM CST Wed Feb 6 2019
A messy wintry mix of precipitation still looks to be on track to
impact the area through the overnight hours. By mid-afternoon, some
showery precipitation was beginning to move into far southwest
portions of the forecast area as some weak shortwave energy was
sliding through. Observations indicated a little bit of everything,
with snow, sleet, and some freezing rain/drizzle; even a few
lightning strikes were seen as some instability slid through. The
mix will continue northeastward through this evening, with a dry
punch aloft moving in behind it leading to a lack of ice in the
cloud layer. Any precipitation should then transition to freezing
drizzle, with soundings showing continued low level saturation
overnight. Overall, looking 0.1 to 0.2" of ice accumulation.
Much stronger energy will then move into the area by Thursday
morning (around 12Z) as a long wave trough continues to slide
eastward, with a surface low tracking northeastward through Missouri
and Illinois. In addition to the stronger lift, much more moisture
aloft will produce mainly snow across the area during the day on
Thursday. Guidance has trended up with QPF during the day, with the
06.18Z RAP showing strong frontogenesis and some slantwise
instability. Therefore, have upped snowfall amounts across the area,
with 3 to 9 inches expected for most. The highest amounts will
generally be north of Interstate 90 and east of the Mississippi
River. A Winter Storm Warning has been issued for counties in this
area, while the Winter Weather Advisory remains in effect
elsewhere.
.LONG TERM...(Thursday night through Wednesday)
Issued at 250 PM CST Wed Feb 6 2019
Surface low lifts northeast into southern Ontario Canada Thursday
evening. The 06.12z GFS/NAM continue to wrap snow across much of the
forecast area Thursday evening...then begin to taper off to flurries
after 06z Friday. The 06.12z GFS/NAM show tight pressure gradient
across the forecast area through Thursday evening. With new fallen
snow and potential for lighter fluffy snow...drifting and blowing
snow can be expected in open areas...especially west of the
Mississippi River.
Colder airmass advects into the forecast area after 06z Friday...as
the 06.12z deterministic models suggest minus 20 to minus 25 degrees
celsius at 925mb by 12z Friday. Combined with the wind...wind chill
values will be in the minus 20 to minus 35 range late Thursday night
into Saturday morning. High temperatures are expected to range in
the single digits below and above zero Friday with low temperatures
falling into the single digits to teens below zero Thursday night
and Friday night. Temperatures warm slightly Saturday...as
shortwave/surface ridge builds into the Great Lakes Region...and
highs should climb into the teens across much of the forecast area.
Main forecast concerns Saturday night through Wednesday are
precipitation chances through the period. The 06.12z GFS/ECMWF/GEM
are in good agreement digging upper level trough over western United
States and moving upper level trough into the Upper Great Lakes
Region through the period. Pieces of energy embedded in the
southwesterly flow aloft/out ahead of the upper level trough will
provide enough lift and forcing to produce snow across the southern
portions of the forecast area late Saturday night into Sunday.
Then...the deterministic 06.12z GFS/ECMWF/GEM lift upper level
trough into the Central United States/Great Lakes Region Tuesday
into Wednesday. This will allow for precipitation across the entire
forecast area. However...confidence of timing of the upper level
trough into the Great Lakes Region Tuesday into Wednesday remains
low. For now...the higher likelihood of precipitation is expected to
fall on Tuesday and Wednesday to be dry. Temperatures through the
period should remain near or slightly below normal...mainly in the
teens and 20s for high temperatures.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 530 PM CST Wed Feb 6 2019
Cigs: holding mostly IFR/MVFR through Thu evening, with improvement
expected late Thu night into Fri morning as high pressure replaces
current winter storm.
WX/vsby: fzdz moves in tonight, lingering into early Thu morning.
Brief period of sleet possible around 00z with convective band
(maybe some T at KRST). FZDZ will swing over to snow around 12z or
so, and then could be heavy at times from mid/late morning into the
afternoon. Winds pick up as the day wears on, with the threat for
BLSN at KRST before 00z. This would likely continue into the mid
evening hours. The bulk of the accumulating snows look to be done by
00z Fri.
Winds: pressure gradient tightens as winter storm pushes northeast
of the area Thu afternoon. Northwest winds will increase and become
gusty, persisting into the evening. Sustained +20 kts with gusts 30-
35 kts expected for KRST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...Winter Weather Advisory until 6 PM CST Thursday for WIZ061.
Winter Storm Warning from 6 PM this evening to midnight CST
Thursday night for WIZ017-029-032>034-041>044.
Winter Weather Advisory from 6 PM this evening to midnight CST
Thursday night for WIZ053>055.
MN...Winter Storm Warning from 6 PM this evening to midnight CST
Thursday night for MNZ079-088.
Winter Weather Advisory from 6 PM this evening to midnight CST
Thursday night for MNZ086-087-094>096.
IA...Winter Weather Advisory until 6 PM CST Thursday for IAZ008>011-
018-019-029-030.
&&
$$
SHORT TERM...CA
LONG TERM...DTJ
AVIATION.....Rieck
Area Forecast Discussion
National Weather Service Caribou ME
1046 PM EST Wed Feb 6 2019
.SYNOPSIS...
A weak weather disturbance will approach from the west tonight and
dissipate to our south on Thursday. Low pressure will approach
Thursday night and track northwest of our area Friday.
&&
.NEAR TERM /THROUGH THURSDAY/...
1030 PM Update...
The last 3 hr trends have shown temps holding the teens and 20s
across the CWA and running higher than the previous
forecast. The 00Z NAM and RAP keep temps up overnight and were
matching well w/the latest conditions. Therefore, raised the
overnight mins up a few degrees. Radar showed some enhanced
returns moving across the region. Most of this was mid level
clouds. However, looking at the obs across southern and sw
areas, some sleet and freezing rain was falling out of a deck
between 4-6k ft. This precip was light. Adjust the wx element to
introduce some sleet across the southern areas overnight at the
start of the precip and then some cooling should allow for
precip to go to some light snow overnight. Also, backed up the
timing of the precip and lowered QPF/SNOW amounts in the 00-06z
time-frame. No changes made to the current Winter Weather
Advisory.
Previous Discussion...
Hi cldnss is already sprdg across the Rgn, spcly across the N
from QB prov as an initial s/wv with a first round of weak low
to mid lvl warm/moisture advcn, mainly in the form of lgt sn
which will ovrsprd the FA from the WSW late this eve and ovrngt.
Ovrngt lows will likely occur during the mid eve hrs before
temps become steady then begin to slowly rise durg the ovrngt
hrs.
Max snfl amts of 2 to 3 inches can be xpctd ovr W and interior SW
ptns of the FA when sn tapers off by erly to mid morn Thu, with 1 to
2 inches ovr E Cntrl and interior Downeast areas and arnd an
inch ovr the far N and Downeast coast. There is a chc that sn
could mix with or even chgovr to lgt sleet ovr Downeast areas
just prior to daybreak, but SREF precip type PoPs show an as the
predominate precip type til about 7 am Thu.
Aftwrds as the initial s/wv moves E of the FA Thu morn, it will
remain cldy and dank as llvl E/ESE winds cont to bring llvl Atlc air
into the Rgn between systems, with either very lgt mixed precip or
lgt patchy fzdz ovr Cntrl/Nrn areas and lgt patchy dz alg the
Downeast coast or patchy dz/fzdz for interior Downeast areas.
Hi temps Thu will be milder than tdy by a few deg F.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
A large area of low pressure will be approaching Thursday night as a
weak weather disturbance slides south of our region. Surface high
pressure will move east across the Maritimes. The combination of the
weak low to our south and the high to our east will hold cold air
near the surface Thursday evening as the big low pulls warmer air
northward aloft. As precipitation moves in late Thursday evening,
temperatures aloft will be warm enough for sleet and freezing rain
across most of the area. Freezing precipitation will be likely
everywhere except coastal Downeast where temperatures should be warm
enough for plain rain. Winter weather advisories will be issued for
all inland areas Thursday evening By early Friday morning freezing
rain will likely persist across the north while Downeast becomes
warm enough for plain rain. Winter weather advisories will be issued
for the freezing rain, overnight for all areas and into Friday
morning for the north. Temperatures will then become warm enough for
plain rain over the north by mid to late morning Friday as the big
low tracks up to our northwest and warmer air works down to the
surface. Rain will end around midday and some breaks of sunshine are
likely Friday afternoon with a mild westerly breeze picking up. Very
large and powerful low pressure will be tracking northeast through
central Quebec Friday night as cold Arctic air circulates around the
low and begins to surge in from the west. Steep lapse rates up to 8K
ft combined with a secondary Arctic cold front may produce some
gusty snow showers or even a localized snow squall Friday evening.
The combination of the big low to our north and high pressure
building to our southwest will bring very strong gusty westerly
winds Friday night through Saturday. Some snow showers are possible
over the far north late Friday night into Saturday morning. Drier
air should then circulate in from the west Saturday afternoon
bringing a trend toward clearer skies from south to north late
Saturday afternoon. Winds Saturday may reach 20 to 30 mph gusting up
to 45 mph.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
High pressure building south of the region will bring a mostly clear
but windy and dry night Saturday night as the giant low lifts away
into Labrador. Sunday will continue to be breezy as the high slide
well south of our area. A small low will then approach late Sunday
night into Monday morning bringing a chance for some light snow,
mainly Downeast into Monday morning. High pressure will then follow
bringing breezy and cold weather Monday night into Tuesday. The high
will slide into the Maritimes, nearby to our north, Tuesday night
into Wednesday bringing continued dry and more tranquil conditions.
Another low may approach late Wednesday night into Thursday morning
bringing a chance of snow, possibly again changing to mixed
precipitation and rain as this low tracks up to our northwest.
Clouds will then likely linger into Friday as an upper trough
remains over the area.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR conditions will hold well into the eve as clgs
lower, then conditions, spcly vsbys, lower to MVFR and IFR
ovrngt and contg into erly Thu morn all TAF sites, as lgt sn
ovrsprds the Rgn from the W. Conditions may briefly improve to
low MVFR clgs mid to late Thu morn, then lower again Thu aftn as
llvl warm advcn conts to slowly moisten the lower atmos. Patchy
fzdz will be possible for spcly Nrn TAf sites by Thu aftn.
SHORT TERM: Conditions will lower to IFR Thursday night and
remain IFR to LIFR into Friday morning. Conditions will then
improve to VFR Friday afternoon. VFR conditions Downeast and
MVFR to VFR conditions over the north are expected Friday night
into Saturday. VFR conditions are expected across the area
Saturday night into Sunday. Very strong gusty west winds from
Friday afternoon through Saturday night will likely result in
turbulent conditions. Mainly VFR conditions are expected
Saturday night through Sunday evening with a reduction to IFR
conditions late Sunday night into Monday. Conditons should
return to MVFR Sunday afternoon.
&&
.MARINE...
NEAR TERM: No hdlns anticipated for the near term. Kept close
to a 12z WW3/NWPS guidance blend for fcst wv hts.
SHORT TERM: Southerly winds are expected to increase to gale
Thursday afternoon, then drop back to SCA Friday, before
shifting to west and becoming a strong gale Friday afternoon
through Saturday night. Cold air over the waters will likely
result in freezing spray, possibly heavy, Saturday into Saturday
night. Winds should drop back to SCA Sunday, then diminish
below SCA Monday as high pressure builds in.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...Winter Weather Advisory from 8 PM Thursday to 10 AM EST Friday
for MEZ001>004.
Winter Weather Advisory from 8 PM Thursday to 8 AM EST Friday
for MEZ005-006-010-011-031-032.
Winter Weather Advisory from 8 PM Thursday to 6 AM EST Friday
for MEZ015>017.
MARINE...None.
&&
$$
Near Term...Hewitt
Area Forecast Discussion
National Weather Service Des Moines IA
544 PM CST Wed Feb 6 2019
.SHORT TERM.../Tonight through Thursday/
Issued at 346 PM CST Wed Feb 6 2019
The weather will be quite changeable through the period with
multiple elements of active weather. Our earlier burst of elevated
instability producing dime to nickel hail in spots of central Iowa
has weakened, but is still sufficient for lingering weak convection
north. The H85 theta-e advection surge has recently blossomed
additional weak sleet and/or freezing rain showers over northern
Iowa with new lightning in spots as well. Farther south light
freezing drizzle continues to expand along and just ahead of the
weak KS/IA 925/850mb inverted trough. Pretty much expect persistent
with this into the evening as the latest RAP shows continued
saturation in that layer, but also with neutral to slightly
subsident vertical motion and weak winds through 03z. Thus the
current Winter Weather Advisory will remain in effect through the
evening and into Thursday for most locations (see below).
Our parent system is still well upstream, just moving through the
Rockies, but should begin advancing through the High Plains
overnight inducing yet another surge of warm/theta-e advection
overnight. Corresponding 1-3km QG forcing will deepen that moisture
eventually leading more toward freezing rain than freezing drizzle,
with increasing frontogenesis toward daybreak as well. Deep forcing
will be in place by 12z with a NW to SE changeover to snow in
progress. There is fairly high confidence in a wintry mix north and
icing south and east, including in the far southeast corner where
lower static stability and proximity to the low level baroclinic
zone may lead to higher QPF. Thus have added a small 12 hour Ice
Storm Warning for three counties in the SE corner where accums may
reach one to three tenths.
Farther north and west snow is expected, but its efficiency (snow
ratio) is somewhat uncertain as some models suggest spotty dendritic
layer moisture, potentially leading to sleet or marginal crystals
lowering amounts. There does seem to be a small three hour or so
window where the dendritic growth zone moisture and omega phase
however so still expecting three to five inch accumulations north.
This will also be coincident with increasing winds as the system
rapidly deepens moving from IL into the Great Lakes. Sustained
speeds should reach 25 to 35 mph with wind gusts 40 mph plus at
times. Thus blizzard potential comes into question. Have left Winter
Weather Advisory in place for this element for now as confidence in
snow type and wind gusts is marginal to go for a Blizzard Warning at
this lead time, but the potential will certainly be highlighted in
products and monitored further. With one to two inch accumulations
down into central Iowa during this windy period, have ended the
current advisory southward and extended until 00z. Also of note
during the windy period Thu will be the potential tree and power
line impacts where significant icing has already occurred.
.LONG TERM.../Thursday night through Wednesday/
Issued at 346 PM CST Wed Feb 6 2019
Long term period begins Thursday evening with ongoing gusty winds
and potential for blowing snow. Strong subsidence should bring most
snowfall activity to an end, however with temp profiles falling
through the dgz cannot rule out a few flurries/light snow showers.
Did not add any mention of lingering -sn to the current forecast due
to low confidence. Models today are a little more aggressive with
the deepening surface low as it crosses the Great Lakes, now
dropping it below 990mb. Tight pressure gradient on the backside of
the low and persistent cold air advection maintains gusty northwest
winds over the state through at least the evening hours. Threat of
blowing snow transitions to another period of bitter cold wind
chills as low temperatures fall below zero Thursday night, with wind
chills dropping to between -20f to -40F. Wind chill headlines will
be needed to highlight the threat, but opted not to issue just yet
due to the complicated winter weather scenario in the short term.
Much lighter winds but continued cold for Friday into Friday night
as an impressive 1050mb high crosses the Upper Midwest. Highs on
Friday will struggle just to get into single digits up north and
teens south, then fall back below zero Friday night.
Upper level ridge axis pushes through the central conus Saturday,
setting up southwesterly flow aloft and lee side cyclogenesis in
southeast CO. Low-level southerly flow/warm air advection will help
temperatures rebound on Saturday. Models in fairly sound
agreement with pushing a weak shortwave through the central Plains
Saturday, however moisture is limited and likely fails to produce
any sensible precip. That story changes as another shortwave
trough quickly follows, this time with better moisture and strong
mid-upper level QG support for lift. Temperatures profiles cold
enough to generate light snow over much the area starting Saturday
night. Precip continues into Sunday before upper level support
gradually wanes.
Not much change to the weather pattern into next week as the wave
train stays active. Models continue to advertise a more robust
system ejecting from the central Rockies Monday into Tuesday. Euro
remains on the faster side of the guidance envelope than the
GFS/GEFS mean, but similar in intensity and track. Potential exists
for a decent shot of snow/blowing snow and impacts to travel over
the region, however it is too far out to start diving into any
specifics just yet.
&&
.AVIATION.../For the 00Z TAFS through 00Z Thursday evening/
Issued at 544 PM CST Wed Feb 6 2019
Numerous considerations. IFR conditions to LIFR at times through
12z southeast; frozen mix at times with -fzra/-fzdz and low
vsbys 1 to 3sm through 13z. As upper level system approaches;
frozen mix changes back over to -sn and winds pick up behind the
system 19-23z with possible blsn north. Significant icing
possible at KOTM 06z to 15z with lighter icing most other sites.
Confidence on ice totals still limited./rev
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 6 PM CST Thursday for IAZ027-028-
033>039-044>050-057>062-070>073-081-082.
Winter Weather Advisory until noon CST Thursday for IAZ074-075-
083>085-092>095.
Winter Weather Advisory until midnight CST Thursday night for
IAZ004>007-015>017-023>026.
Ice Storm Warning from midnight tonight to noon CST Thursday for
IAZ086-096-097.
Winter Weather Advisory until midnight CST tonight for IAZ086-
096-097.
&&
$$
SHORT TERM...Small
LONG TERM...Martin
AVIATION...REV
Area Forecast Discussion
National Weather Service Goodland KS
839 PM MST Wed Feb 6 2019
.UPDATE...
Issued at 804 PM MST Wed Feb 6 2019
Just completed an update. Currently a narrow intense band of snow
has developed over the eastern half of the forecast. This is a
little east of what was earlier expected. High resolution,
specifically the Arw, Rap, and Hrrr have picked up on this band
nicely. This band matches up well with where the larger scale
output has very strong frontogenesis collocated with theta-e lapse
rates near or a little below zero.
Fortunately this band is moving through rather quickly, and should
be done/east of the area by late this evening. Also accumulating
snow for the entire area should be done by 12z. As a result of
this band affecting locations further east than expected, raised
pops in the above mentioned area, increased qpf and snowfall
amounts. The eastern portion of the area now is expected to
receive 2 to almost 3 inches.
With a large portion of the area having this light and fluffy
snow on the ground, have inserted blowing snow into the forecast
into the morning hours on Thursday. Cold temperatures and wind
chill values still look on track.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 337 PM MST Wed Feb 6 2019
A Winter Weather Advisory remains in effect through 18Z Thursday.
Remaining areas of freezing fog and freezing drizzle across the
forecast area will diminish as the transition is made to all light
snow this evening. There is a band of higher reflectivity returns
showing up on the radar that is moving quickly eastward across the
region late this afternoon and evening. Within this band of higher
returns, snowfall rates will be briefly 1-2" per hour. Even with
a brief period of moderate to heavy snowfall transitioning the
area, total snowfall amounts should remain less than 3 inches.
Snowfall is expected to diminish after midnight tonight as the
system lifts quickly out of the southern plains early Thursday
morning towards the Great Lakes by Thursday afternoon. Areas of
flurries may remain through the day on Thursday with the cold air
remaining firmly entrenched through Thursday night. Overnight lows
Thursday night will be nearly identical to tonight, with the main
difference being the winds. North winds of 20-30 mph tonight will
continue into Friday morning. Combined with ambient air
temperatures between -3 and +8 Thursday morning, Wind Chills
between -15 and -25 are expected, which warrants the continuation
of the Winter Weather Advisory through tonight and Thursday
morning. With winds becoming light Thursday night, no wind chill
advisory is anticipated with the similarly cold temperatures
expected early Friday morning.
.LONG TERM...(Friday through Wednesday)
Issued at 314 PM MST Wed Feb 6 2019
The extended forecast will be active with a couple of shortwave
troughs moving through the region. Friday morning, an upper level
trough will extend from central Montana to the Great Lakes.
Northwest flow aloft over the region will transition to southwest
flow during the day as an upper level trough over the northwest
deepens.
A low forming on the lee side of the Rockies will extend into the
Tri-State region Saturday night into Sunday. Still looking at
relatively dry conditions, so no PoPs mentioned. A cold front will
swing south through the area Sunday, dropping temperatures through
the day. Expected high temperatures will be in the 20s and 30s.
Another trough will move into the region on Monday. A chance of
rain and snow is present Monday and Tuesday, though confidence any
amounts and coverage is low at this time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 414 PM MST Wed Feb 6 2019
Snow band with moderate to possibly heavy snow is beginning to
work its way across the area. Behind this band the snow will let
up and end with additional fog development. For Kgld, ifr/lifr
conditions are expected through 02z with northeast winds of 15
knots with gusts around 23 knots. From 02z to 13z mvfr conditions
will prevail north winds near 15 knots. However in the 04z to 06z
time frame there will be a brief period lifr conditions with the
north winds gusting to 23 knots. From 13z to the end of the
period, vfr conditions and north winds around 17 knots are
expected.
For Kmck, mvfr conditions will quickly transition to ifr/lifr at
01z as the main snowband starts affecting the site. Those
conditions along with northeast winds of 15 knots with gusts to
near 23 knots will last until 06z. At 06z vfr conditions return
and will last until the end of the period. From 06z to 08z the
north winds near 16 knots with gusts to around 24 knots will
continue. At 08z the north to northwest winds stop gusting with
winds remain near 17 knots through the remainder of the period.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...Winter Weather Advisory until 11 AM MST /noon CST/ Thursday for
KSZ001>004-013>016-027>029-041-042.
CO...Winter Weather Advisory until 11 AM MST Thursday for COZ090>092.
NE...Winter Weather Advisory until 11 AM MST /noon CST/ Thursday for
NEZ079>081.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...AW
AVIATION...BULLER
Area Forecast Discussion...CORRECTED
National Weather Service Green Bay WI
934 PM CST Wed Feb 6 2019
CORRECTED HEADLINE CODING
Updated aviation portion for 06Z TAF issuance
and new information added to update section
.UPDATE...
Issued at 912 PM CST Wed Feb 6 2019
Was close to delaying the onset of the Winter Storm Warning until
6 am, but OSH and ISW have come in with FZRA and UP. So will stay
the course with a 06Z start but rework the wording to highlight
that we`ll only have light precipitation tonight and the worst
conditions won`t occur until tomorrow.
The 00Z models are coming in and still present somewhat mixed
signals for the locations of the rain/snow line during the period
of heavy precipitation tomorrow. The extended run of the HRRR at
00Z was similar to the 18Z GFS with 5-6 inches of snow at GRB. The
00Z NAM maintains more of a warm layer and a FZRA/IP sounding. We
are dealing with very subtle differences in temperature, basically
flirting with the level of predictability of the models, so
it`s unlikely we will get this clearly resolved until we see how
the precipitation behaves tomorrow morning.
Edged snow totals N and W of GRB up a bit to try and sharpen the
gradient in that area.
Updated product suite will be out ASAP.
UPDATE
Issued at 618 PM CST Wed Feb 6 2019
The active pattern will continue as southwest flow sends another
weather system into the area--this time a rapidly deepening
cyclone that will race northeast from the Southern Plains on
Thursday.
Headlines for tonight are the first concern. A lead shortwave
ejecting out of the Southwest U.S. upper trough was generating a
band of mixed precipitation from near RST-MSN-RFD early this
evening. That will continue lifting north during the evening--
crossing much of the area prior to the onset of the Winter Storm
Warning. If the mixed precipitation transitions to mainly snow as
it reaches the area, we`ll be okay because it would only generate
an inch or two of snow as it is likely to remain narrow and
progressive. But freezing precipitation would have a much greater
impact and would probably necessitate starting the Warning
immediately. We currently have flurries in GRB, and thermal
profiles are cold enough for snow if we get deep/cold enough
saturation-- which may occur in the band. Will be watching the
evolution of precipitation type as the band shifts north, and may
need to start the warning early if we end up with mainly
FZRA/FZDZ. But would prefer not to do that because...
There is likely to be a significant lull in the precipitation
behind the lead band and the main surge of precipitation with the
primary cyclone. Will consider delaying the onset of the warning
until early tomorrow morning (~ 6am) if we don`t need it start it
this evening.
The final concern is precipitation type on Thursday. It`s always
tough when one of these rapid deepeners comes racing up just to
your east. Periods of lighter precipitation across most of the
area may be FZRA/FZDZ due to saturation being of limited depth.
But there will be a period mid-day when the intense forcing shifts
through that the saturation will be deep enough for ice crystals
everywhere. Precip type will then be modulated by the presence or
lack of an above freezing layer aloft. The concern is a swath
from ATW-GRB and just to the northwest. Model forecast soundings
in this area are generally within a degree or so of having all
snow during the period of max lift. If that were to occur. A burst
of 4-8 inches of snow could occur within a few hours mid-day,
before the precip changes to FZDZ as the upper dry slot surges
across from the south. The 18Z GFS actually shows this, with
BUFKit showing a COB-11 snowfall of 6.6 inches at GRB between 15Z
and 21Z.
Do not plan any major forecast changes at this time, but will
issue an SPS detailing some of the high-impact aspects of the
forecast during the next 24 hours.
&&
.SHORT TERM...Tonight and Thursday
Issued at 209 PM CST Wed Feb 6 2019
Despite the departure of the snow that fell overnight, cloudy
skies continued to plague the forecast area this afternoon. There
won`t be much of a respite from the active weather pattern as more
precipitation is on the way later tonight and into Thursday as a
low pressure system tracks to the southeast of the area.
Precipitation will start later tonight as the region gets under
the left exit region of a strong upper level jet with mid level
isentropic lift as the warm air advection portion of the system
approaches the western Great Lakes region. There will be issues
saturating the atmosphere enough to create ice crystals, with
quite a bit of freezing rain expected especially in the southern
half of the forecast area. There will be a better chance for all
snow across the north, however freezing rain will still be on the
table according to model soundings.
The brunt of the system will approach on Thursday as the low
undergoes rapid cyclogenesis and deepens close to the rate of a
"bomb". The area will be underneath the TROWAL on Thursday, with
moderate to heavy precipitation rates during the late morning and
afternoon hours.
Precipitation type will be a mixed bag as dry air in the mid
levels keeps freezing rain on the table for just about everywhere
Thursday morning, with mainly snow across the north and west later
Thursday afternoon when the main TROWAL arrives and the moisture
becomes deep enough for mainly ice crystals to fall. Further east
there will be issues getting all snow even Thursday afternoon as
even when we saturate enough to get ice crystals, low level warm
layers melt some of the snow to create sleet or melt it all the
way for freezing rain. Overall this is a very complex forecast
with many precipitation types expected from later tonight through
the day on Thursday.
Once the event is over snowfall totals are expected to range from
6 to 11 inches across north-central, with 4 to 8 inches across
western portions of central, 3 to 5 across the rest of central and
northeast, and up to 3 inches across east-central Wisconsin and
the lake shore. In addition to the snow, ice accumulations could
accumulate to around one quarter of an inch or more across east-
central Wisconsin and the lake shore, with one to two tenths
across central and northeast Wisconsin. Further north a few
hundredths to up to a tenth of an inch is possible. Given this
complex weather scenario will opt to issue a Winter Storm Warning
instead of parsing out the different precipitation type scenarios
with Ice Storm Warnings and Winter Storm Warnings. The thinking is
if criteria is not reached on the snowfall front, it will be
reached with the ice that is expected. Also if the storm track
shifts it will make managing the headlines easier on subsequent
shifts. If the forecast looks to be solid ice instead of snow,
headlines can be adjusted for an Ice Storm Warning in subsequent
forecasts.
.LONG TERM...Thursday Night Through Wednesday
Issued at 209 PM CST Wed Feb 6 2019
A lingering upper trough over the Great Lakes behind the departed
storm will bring a bout of arctic air into WI for Friday through
Monday. A new, strong upper trough is forecast to move inland into
the western Great Lakes early next week and turn the mean flow to
a southwest directions into WI, allowing for temperatures to
moderate. There are timing issues with respect to the movement of
this upper trough across the central CONUS during the Tue/Wed time
frame with potential for heavy snow. Not as much cold air behind
this system, thus temperatures to be at or slightly below normal
mid-week.
The strong surface low will continue to track northeast into
southeast Canada with enough lingering lift and mid-level forcing
from a cyclonic flow, to keep light snow in the forecast through
Thursday evening. Additional snow accumulations to range from less
than one-half inch over southern sections of the forecast area, to
a couple of inches across far northeast WI. This would bring
totals into the 1-3" range east-central WI, 7-11" northern WI.
While synoptic snows end later Thursday evening, a wind shift to
the west-northwest and strong CAA will lead to lake effect snow
showers over north-central WI with up to an inch of accumulation
over Vilas County. Min temperatures to drop into the zero to 5
below range central WI, around 5 above zero near Lake MI. Wind
chills plummet into the -10 to -20 range with possible advisory
conditions reached over central WI. The minor lake effect snow
showers are expected to linger into Friday morning before starting
to diminish as high pressure starts to build into the region from
the Upper Midwest. Anticipate some sunshine to return on Friday
(mainly in the afternoon), but with arctic air overhead,
temperatures will be well-below normal. Look for readings to only
reach around 5 above zero central WI, mainly 5 to 10 above zero
eastern WI.
This area of high pressure moves into the western Great Lakes
Friday night, bringing mostly clear to partly cloudy skies,
diminishing winds and very cold conditions. Near ideal radiational
cooling conditions (plus the fresh snow) should allow temperatures
to free-fall. Min temperatures to range from around 5 below zero
near Lake MI, 15 to 20 below zero over the colder spots of north-
central WI. As the surface high slides to our east on Saturday,
winds will shift to the south and usher in some `warmer` air aloft
(8H temperatures climb into the -14 to -7C range by 00Z Sunday).
This could bring a general increase in clouds and keep max
temperatures to only the 10 to 15 above zero range over most of
northeast WI.
Saturday night will remain quiet and not as cold with more cloud
cover acting as a blanket. A weak shortwave trough located well to
our south on Sunday could bring a small chance for light snow into
southern parts of the forecast area. Otherwise, plenty of clouds
are expected over the region with max temperatures on Sunday to
range from the middle to upper teens north-central WI, upper teens
to lower 20s elsewhere. This little system exits Sunday evening,
allowing high pressure to move into the Great Lakes for Sunday
night through Monday. This should leave skies generally partly
cloudy with temperatures running 5 to 10 degrees below normal.
This would bring max temperatures on Monday into the upper teens
to lower 20s.
Confidence remains very low with respect to the next potentially
big winter storm to move across the central CONUS/Great Lakes
toward the middle of next week. The models are different with the
timing of the storm, different with the storm track and
potentially different with precipitation type. We will need to
watch this system closely in the coming days as heavy snow will
fall somewhere over the Upper Midwest/western Great Lakes Tuesday/
Tuesday night. For now, have followed the consensus solution which
runs chance pops from Monday night through Tuesday night and
possible lake effect snow showers over Vilas County on Wednesday
as winds shift to the northwest behind the storm. Below normal
temperatures should persist through Wednesday.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 912 PM CST Wed Feb 6 2019
Widespread low-end MVFR conditions prevailed across the area late
Wednesday evening. Little change is anticipated overnight. A
rapidly deepening cyclone will race northeast from the Southern
Plains Thursday, bringing widespread wintry weather to the area
and creating poor flying conditions.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from midnight tonight to midnight CST
Thursday night for WIZ005-010>013-018>022-030-031-035>040-045-
048>050-073-074.
&&
$$
UPDATE.........Skowronski
SHORT TERM.....Kurimski
LONG TERM......Kallas
AVIATION.......Skowronski
Area Forecast Discussion
National Weather Service Indianapolis IN
1008 PM EST Wed Feb 6 2019
.UPDATE...
The Near Term and Aviation sections have been updated below.
&&
.SYNOPSIS...
Issued at 238 PM EST Wed Feb 6 2019
A warm front is expected to linger across Central Indiana Tonight
and early Thursday. This will be the focus for rain tonight and
again on Thursday. This may result in flooding and a FLOOD WATCH
remains in effect for much of Central Indiana.
Low pressure is expected to push toward the Great Lakes on
Thursday night from the southern plains. The low will drag a cold
front across Central Indiana and bring more rain showers on
Thursday afternoon...perhaps lingering into the evening.
Colder and dry air is expected to arrive on Friday as Canadian high
pressure builds across the Upper midwest and Ohio Valley. This
will result in a dry but cold start to the weekend.
More chances for precipitation will return on late Sunday and
Monday as an area of low pressure is expected to push through the
Ohio Valley.
&&
.NEAR TERM /Tonight/...
Issued at 1008 PM EST Wed Feb 6 2019
Adjustments to pops made per radar trends and HRRR progs, which
appear to be tracking well with observed precipitation so far this
evening. Will likely see a bit of a lull in some areas followed by
another substantial batch of showers and perhaps an embedded storm
or two later tonight. Dense fog will also be a concern at times,
although may or may not be widespread enough to merit advisory.
Dense fog has been mostly localized up to this point. Previous
discussion follows.
Issued at 238 PM EST Wed Feb 6 2019
Surface analysis early this afternoon shows a frontal boundary
stretching from srn Illinois across central Indiana to nrn Ohio.
Water vapor imagery continues to show a plume of tropical moisture
steaming across Mexico...into Texas and then northeast to the
Ohio Valley. A deeper trough aloft was found over the
intermountain west. High pressure over the southeastern states
was continuing to provide a warm and southerly flow of air to the
Ohio Valley. Temperatures ranged from the upper 30s north to the
lower 60s south as did the dew points across the area.
The GFS and NAM again suggest another short wave aloft poised to
push across Central Indiana this evening. As this upper wave
passes...best forcing and support is found mainly across the
southern parts of the forecast area where HRRR generates much of
the precip. 300K GFS Isentropic surface shows very good up glide
tonight with specific humidities over 6 g/kg...again very high for
this time of year. Forecast soundings show deep moisture in place
along with pwats over 1 inch. All of this along with the tropical
plume aloft means that plentiful moisture will be available with
the previously discussed short wave and forcing passing. Thus will
trend pops at or above the forecast builder blends...particularly
across the southern parts of the forecast area...trending lower at
points north where forcing is less favorable. Given the expected
clouds and precipitation will trend lows at or above the blends.
&&
.SHORT TERM /Thursday through Saturday/...
Issued at 238 PM EST Wed Feb 6 2019
The deep trough aloft over the western United States will progress
eastward on Thursday...allowing an area of surface low pressure
over the southern plains to push northeast along the warm frontal
boundary toward the Great Lakes. The passing low pressure system
will push a cold front across Indiana. Again plentiful moisture
will remain in place ahead of the front. Forecast soundings show
deep saturation once again with pwats over 1.4 inches. Thus will
again use high pops on Thursday...and begin to taper things off on
Thursday night as the frontal passage will be expected early in
the evening....however the bulk of the precip should be over by
00Z as the models suggest dry air invading the column. Thus will
trend pops lower rapidly with the onset of of dry air. Will stick
close the forecast builder pops and temps on Thursday night.
Strong high pressure is expected to build across Indiana on Friday
and Saturday as ridging aloft strengthens across the plains states
through the period. This will result in lee side subsidence across
the Great lakes and Ohio valley on Friday through Saturday along
with cold N-NW lower level flow. Thus will trend toward partly
cloudy days and nights and trend temps at or below the forecast
builder blends due to the colder air mass that is expected.
&&
.LONG TERM /Saturday night through Wednesday/...
Issued at 245 PM EST Wed Feb 6 2019
Models in good agreement that ridging will provide dry weather
Saturday night. After that a western system will eject disturbances
our way in southwest flow. Models as to be expected have issues
agreeing on timing with these subtle waves. In addition, models are
have temporal, spacial and strength issues with the evolution of the
western system. So, confidence is low in any one solution, but
overall it looks like an active period per the blend with potential
for snow, rain and a mix at times starting Sunday. With confidence
low, will accept the blend PoPs and temperatures.
&&
.AVIATION /Discussion for the 07/03Z TAF Update/...
Issued at 1008 PM EST Wed Feb 6 2019
Brief improvement in ceilings at some sites is not expected to
last long with widespread IFR or worse ceilings upstream. Have
made minor adjustments to some TAFs but the general TAFs remain
valid. Previous discussion follows.
Issued at 622 PM EST Wed Feb 6 2019
Poor flying conditions will continue through the majority of the
period as widespread IFR or worse conditions persist.
IFR conditions and MVFR visibilities will likely deteriorate again
tonight, with LIFR conditions likely at all sites in rain showers
and fog.
Winds will be light and variable early in the period, gradually
swinging around to the southeast, south, and then west as the
period wears on. Speeds will strengthen tomorrow to around 10-15KT
with gusts around 25-35KT.
While thunder cannot be ruled out, it is too low probability at
this time for an explicit mention.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
Flood Watch through late Thursday night for INZ039>042-045>049-
051>057-060>065-067>072.
&&
$$
SYNOPSIS...Puma
NEAR TERM...Puma/Nield
SHORT TERM...Puma
LONG TERM...MK
AVIATION...Nield
Area Forecast Discussion
National Weather Service Louisville KY
943 PM EST Wed Feb 6 2019
.Forecast Update...
Issued at 930 PM EST Wed Feb 6 2019
Scattered to numerous showers, mostly light to briefly moderate at
times continue over south-central IN and a good part of central KY.
However, the main area of concern for heavy convective rains, and
even occasionally strong to severe cells, has been across TN where a
mesoscale boundary remains quasi-stationary and oriented roughly
west to east, reinforced by the convective rainfall as it trains
along and just north of the boundary. This has resulted in less
rainfall late this afternoon and evening over much of central KY.
However, latest radar trends show that some of the heavier rain over
TN is now affecting our southern row or 2 of south-central KY
counties, as the rain moves ENE.
Latest high-res models including the HRRR suggest the boundary will
remain over TN for the next few hours, which makes sense given no
significant shortwave aloft to lift the boundary north into central
KY overnight, and given the ongoing convective rains. Thus,
significant rains for the next few hours will be confined to south-
central KY where some training may occur, so will have to watch for
significant ponding and localized flooding in this area.
Models differ somewhat getting closer to Thu daybreak as to expected
evolution. A couple high-res models lift the current convection into
eastern TN and SE KY as it weakens, while others suggest some
renewed activity coming into south-central KY later. There is also a
sense that the western part of the boundary may start to lift NE
into SW/central KY toward daybreak as the main wave aloft starts to
eject well to our west. If this is the case, then slowly
strengthening low-level winds from the S and SW would allow precip
to begin redeveloping farther north into western and central KY and
SW/south-central IN. Eventually, the boundary will continue to push
north through the area on Thu as the main shortwave continues its
approach and low-level winds back and strengthen.
Temps overnight will remain nearly steady and could even rise a
couple degrees. With weak surface winds and a very small surface
temp-dewpoint spread, there could be at least patchy fog north of
the boundary, so will add patchy fog to the forecast.
&&
.Short Term...(This evening through Thursday Night)
Issued at 230 PM EST Wed Feb 6 2019
Wet scenario for the short term, with multiple waves crossing the
region. After this morning`s pass, another weaker wave should bring
rains to the Wabash later this afternoon as well as reignite some
precip along an effective boundary near the KY/TN border. The first
system likely will bring a brief wave of rain across the northern
two-thirds of the region tonight, whereas the southern focus will
bring more prolonged rain chances. That boundary should move slowly
north, possibly reaching the Pkwys in KY by daybreak Thursday. These
fine scale motions are what will trigger our hydro issues, and it
still is early to be certain about these. Thus the Flood Watch
areawide still looks good.
As for the severe threat this afternoon and tonight. The rains have
helped to cool us down some/stabilize the area. Think to focus for
any issues this evening will be closer to that effective boundary
along our southern border. As the night continues, expect a narrow
band where the shear and instability may be able to work together to
produce a supercell or two, again over southern KY. Should the
effective boundary move faster northward, that corridor would shift
with it.
As Thursday morning moves along, we should see coverage of showers
diminish for most of the area, though southwest Indiana will have
the best chance to keep in some rains through the morning hours.
With a little more sunshine possible, expect us to tap into a
tightening pressure gradient, and consequently stronger wind gusts.
We could get near wind advisory criteria. MAV guidance gets in the
low 20 knots for sustained winds, and this typically indicates
potential to get up to 40 mph for gusts. Those strong south to
southwest winds likely will help us break some records...see climate
discussion below.
That near record heat will set the stage for a line of strong to
severe storms to roll through here later Thursday afternoon and
evening. Latest hi-res guidance has trended just a tad slower for
this line to move through the region...with it reaching the I-65
corridor in the 4-8 PM time frame and I-75 in the 6-10 PM time
frame. At this point, feel the model soundings are underestimating
the instability, showing temperatures at onset of precipitation in
the mid 60s, when it probably will be higher. In similar recent
setups though, that heating has helped to produce showers ahead of
the main line that effectively rob the instability to feed that
line. Will have to watch. CIPS analogs highlight an area along and
west of I-65 with a chance for some severe reports, so will continue
to highlight the threat.
.Long Term...(Friday through Wednesday)
Issued at 312 PM EST Wed Feb 6 2019
...BRIEF BREAK IN THE WEATHER PATTERN FOR FRIDAY AND SATURDAY...
...ACTIVE WEATHER PATTERN EXPECTED FOR MUCH OF NEXT WEEK...
...ADDITIONAL RAINFALL THREATS MAY POSE ADDITIONAL FLOODING ISSUES...
==============================
Friday through Saturday Night
==============================
By Friday morning surface cold front is expected to be east of
Kentucky with the back edge of the precipitation shield likely over
far eastern KY. Temperatures will start off very cold with readings
in the lower to middle 20s. Temperatures during the afternoon are
not expected to move all that much with highs in the upper 20s over
southern Indiana and in the 30-35 degree range over much of central
Kentucky. Combination of clearing skies and light winds will allow
a decent radiational cooling night for Friday night and Saturday
morning. Temps Saturday morning look to cool into the 13-18 degree
range region wide. With high pressure to the northeast of the
region, we`ll see mainly an southeasterly flow develop. Some
moderation in temps are likely with highs only warming into the 35-
40 degree range. Winds look to become more southerly Saturday night
and Sunday morning as temps will only drop into the lower-mid 20s.
==============================
Sunday through Wednesday
==============================
The next weather system is poised to affect the region on Sunday. If
precipitation develops quick enough, the northern edge of this
precipitation could start off as a wintry mix before going over to
rain. Rain is likely through the afternoon and into Sunday evening.
Highs Sunday look to warm into the upper 30s to the lower 40s across
southern IN and northern KY, with lower-mid 40s across southern KY.
Lows Sunday night look to drop into the mid 30s in most locations.
Some colder air may work its way down into our northern row of
southern Indiana counties (per the GFS/FV3 solutions). However, the
Euro has been trending warmer here, keeping wintry weather well
north of the region.
The Monday through Wednesday time frame will be quite unsettled. A
robust southern Jet stream of Pacific origin will keep milder air
and plenty of moisture flowing in across the southern Plains and
into the Ohio Valley. Baroclinic zone looks to be just north of
here with the Ohio Valley likely remaining on the warm side of the
zone. Should this occur, we will be looking at additional periods
of moderate to heavy rainfall which will only aggravate already
saturated soils. This could very well lead to additional flooding
and longer episodes of river flooding.
Toward the end of the period (Tuesday night/Wednesday), a sharp
upper trough looks to move through the region with a surface low
cutting from the TX/OK panhandle northeastward into the Great Lakes.
This would drag another cold front through the region late Tuesday
with a cooler airmass working back into the region.
Highs Monday look to range from the lower 40s over southern IN and
northern KY. Mid upper 40s are likely over southern KY. Ahead of
the cold front on Tuesday, we`ll warm back up into the lower-mid 50s
over the north with upper 50s and possibly 60s over the south. Highs
on Wednesday look to go back into the 40s. Overnight lows through
the period will generally be in the 30s, with some 20s possible by
Thursday morning.
&&
.Aviation...(00Z TAF Issuance)
Updated at 654 PM EST Wed Feb 6 2019
Messy weather will continue across the TAF sites through this period
as a frontal boundary wavers across the region, and waves of low
pressure ride along it. Expect intermittent showers through through
the overnight, with the best chance at a T-storm down a BWG.
Otherwise, precipitation should be pretty light at HNB/SDF/LEX.
Ceilings are variable between MVFR and VFR, with occasional dips
down to IFR possible. Not very high confidence in ceilings or
visibility overall tonight.
The frontal boundary will lift north of the area as a warm front
into the day on Thursday, with gusty SSW winds taking hold and near
record warmth. We`ll be mostly dry through the morning and the first
part of the afternoon, although a few showers will still be around.
A strong line of showers and some storms will then move through
later Thursday afternoon into the evening, followed by a cold front.
We should see a return to mostly high MVFR or VFR during the late
morning and afternoon as the warm sector gets established.
&&
.Climate...
Issued at 200 PM EST Wed Feb 6 2019
Listed below are the record highs and forecasts for today and
Thursday.
Site 2/6 2/7
Rec. (Yr) Fore. Rec. (Yr) Fore.
SDF 70 (2008) 65 69 (1925) 70
LEX 67 (1925) 64 67 (1925) 70
BWG 69 (2008*) 67 71 (1931) 73
FFT 68 (2008*) 65 69 (1925) 69
Listed below are the record warm lows and forecasts/obs for
today and Thursday. The caveat with Thursday`s data is that
the front will move through before midnight, likely pulling
readings down below record levels. LEX stands the best chance
to break their record, should the timing of the frontal
passage slow down.
Site 2/6 2/7
Rec. (Yr) Fore. Rec. (Yr) Fore.
SDF 51 (1904) 51 55 (2017*) 39
LEX 47 (1904) 57 54 (2017) 44
BWG 55 (1938) 63 52 (2017*) 41
FFT 54 (1927) 53 56 (2017) 42
In addition to the warmth, a very moist airmass over the region
likely will bring record rainfall. Below are the record rainfall
amounts by date for Wed/Thu for each of our climate sites.
Site 2/6 Record (Year) 2/7 Record (Year)
SDF 2.21" (1883) 1.09" (1890)
LEX 1.39" (2008) 1.30" (1890)
BWG 1.30" (2008) 1.05" (1933)
FFT 1.76" (1955) 0.87" (2018)
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...Flood Watch through late Thursday night for INZ076>079-083-084-
089>092.
KY...Flood Watch through late Thursday night for KYZ023>043-045>049-
053>057-061>067-070>078-081-082.
&&
$$
Update..,,,,.TWF
Short Term..,RJS
Long Term..,.MJ
Aviation..,,.BJS
Climate.,,,..RJS
Area Forecast Discussion...UPDATED
National Weather Service Mobile AL
558 PM CST Wed Feb 6 2019
.DISCUSSION...Updated for latest aviation discussion below.
&&
.AVIATION...
00Z issuance...IFR to LIFR conditions are expected to develop
shortly after 07.01z and continue through 07.15z followed by IFR
to MVFR conditions through 08.00z. Visibilities and ceilings will
begin to deteriorate shortly after sunset and continue through mid
morning gradually improving through late afternoon. Winds will be
southerly at 5 to 10 knots through 08.00z. 32/ee /7
&&
.PREV DISCUSSION... /issued 336 PM CST Wed Feb 6 2019/
NEAR TERM /Now Through Thursday/....06.12Z upper air analysis
shows a northeast to southwest oriented ridge axis from the Mid-
Atlantic to the Gulf, while a sharpening upper trof was positioned
over the Intermountain West. At the surface, synoptic scale high
was centered off the US east coast. West of the high, a warm,
moist southerly flow is forecast to persist going into Thursday.
For tonight, a persistence type approach will be taken which
favors another round a dense fog formation over much of the area.
SREF probabilities of visibility lowering to a mile or less is 60
to 90% over the southern zones, focused along the coastal
counties. The high res. RAP and NAM12 favor the development of
extensive fog, visibility lowering to at or less than a quarter
mile along and southeast of I-65. The HRRR also shows dense fog,
but not with the widespread coverage as the NAM12 and RAP.
Considering the output from 3 out 4 guidance fields, A dense fog
advisory will be issued for tonight, which will carry over into
mid to late Thursday AM.
As far as temperatures, may see warm low temperatures tonight
near record levels over several areas. Thursday, strengthening
warm air advection ahead of a strong cold front diving into the
Lower MS River Valley late in the day, supports very un-February
like temperatures with near record warmth being advertised with
highs lifting up into the upper 70s to perhaps the lower 80s. A
small chance of showers over the western zones Thursday.
Here`s a sampling of the latest records (Lows/Highs) for Thursday
that could be matched or broken.
Mobile- 65/78,
Pensacola - 66/79,
Crestview - 58/80
Evergreen - 59/77,
Waynesboro - 63/82,
/10
SHORT TERM /Thursday night Through Saturday night/...A vigorous
shortwave trough currently moving through the longwave trough over
the western states will propagate east and then northeastward
driving a cold front across the region Thursday night. Main
dynamics and upper forcing with this system will be displaced well
to the North of our area. Expect only some light shower activity
along and behind the front as it sweeps southeastward into
Southeast Mississippi and Southwest Alabama Thursday evening and
east of Northwest Florida and South Central Alabama after
midnight. Surface high pressure over the Eastern Gulf will keep a
warm moist southerly surface flow going ahead of the front
allowing for fog to spread inland during the evening hours
Thursday night and scour out in the wake of the front. Behind the
front, Northerly surface winds will advect in drier air scattering
out the low level moisture and cloud cover but mid and high level
cloud cover will continue to advect over the area through
Saturday. Surface winds are modeled to veer to a east to
southeasterly direction Saturday night as surface high pressure to
the north shifts east to the eastern seaboard. Overnight
radiational cooling inland will probably assist in keeping surface
winds from a Northeast to Easterly direction, but the flow above
the boundary layer will likely become southeasterly creating
isentropic ascent and the gradual saturation of the low levels
resulting in some overnight fog development. Overnight lows
Thursday night will be greatly dependent on the passage of the
cold front. This forecast package has Thursday night minimum
temperatures ranging from low to mid 40s over Wayne and Choctaw
counties to mid to upper 50s over South Central Alabama and
Northwest Florida. Daytime highs Friday and Saturday will trend
cooler than climatological normals for a change: ranging from the
low to mid 50s west of the I-65 corridor and upper 50s to low 60s
east. Lows Friday night dip into the mid 30s inland to low to mid
40s along the coast and upper 30s to lower 40s over interior
locations to near 50 along the immediate coastline Saturday night.
/08
LONG TERM /Sunday Through Wednesday/...A southerly return flow
develops Sunday as a broad area of surface high pressure shifts
eastward over the Western Atlantic. As a result, temperatures and
moisture begin to climb and overnight-morning fog returns to the
region. A southwesterly flow is expected to prevail aloft creating
the possibility of passing shortwave troughs triggering some
isolated to scattered shower activity in the warm sector overlying
the region Sunday night through Tuesday. Another cold front is
progged to move across the region Tuesday night bringing increased
shower activity with it and gradual drying and cooling in its
wake. /08
MARINE...Main hazards in the near term will be low visibility in
dense fog. A warm, southerly, moist flow (dewpoints in the mid to
perhaps upper 60s), atop cooler bay and inland waterways (where
water temperatures range in the mid to upper 50s) support a pattern
for persistent advective type fog in the near term. A strong cold
front makes passage late Thursday night to around day-break Friday
which scours out fog and moisture. In the wake of the frontal
passage, small craft advisories will likely be required due to an
evolving strong offshore flow and building seas to close out the
week. /10
&&
.MOB WATCHES/WARNINGS/ADVISORIES...
AL...Dense Fog Advisory until 10 AM CST Thursday for ALZ056-059-060-
261>266.
FL...Dense Fog Advisory until 10 AM CST Thursday for FLZ201>206.
MS...Dense Fog Advisory until 10 AM CST Thursday for MSZ078-079.
GM...Dense Fog Advisory until noon CST Thursday for GMZ630>636-650-
655.
&&
$$
This product is also available on the web at:
http://weather.gov/mob
AREA FORECAST DISCUSSION
National Weather Service Charleston WV
701 PM EST Wed Feb 6 2019
.SYNOPSIS...
Periods of rain, mainly across southern sections through early
Thursday morning. Strong cold front Thursday night. Cold high
pressure this weekend.
&&
.NEAR TERM /THROUGH THURSDAY/...
As of 450 PM Wednesday...
Adjusted PoPs and Weather grids per latest radar imagery trends.
This resulted in lowering PoPs areawide, as rain showers
exit east, faster than anticipated. Also, went more
deterministic across northern portions of southeast Ohio and WV,
cutting PoPs below 15 percent through the overnight hours. Any
pcpn there should be drizzle if anything. Additional periods of
rain are still expected across northeast KY, southwest VA and
southern half of WV into the predawn hours Thursday.
Expanded areas of dense fog west from the northeast mountains,
west and south, to cover northern portions of southeast OH and
West Virginia through early Thursday morning. Latest HRRR model
is in agreement with this thinking.
Hourly temperatures were revised and matched with past
observations resulting in couple degrees lower for High
temperatures this afternoon.
Rest of forecast remains on track.
As of 135 PM Wednesday...
Impressive low level theta e axis embedded within a belt of
stout low level moisture advection continuing to give southeast
OH moderate to heavy rain. Amounts to 2 inches are now being
reported in spots with several flooded roads. Models agree on
pushing this axis southeast as the surface wave departs this
afternoon, with a bit of a progressive nature to it. This
should keep rainfall amounts closer to 1 inch rather than the 2+
that has been observed across southeast OH. This continues this
evening with the boundary draped across far southern zones.
This would allow for a much needed lull across southeast OH,
northeast KY, and northern/western half of WV. The sharp low
level theta e boundary along with some weak instability aloft
keeps some thunder mention as it moves through the area with
some beefy rainfall rates for this time of year.
The axis stays draped in the vicinity of our southwest VA
counties overnight with rounds of moderate to occasionally
heavy rain pegged by the models. This is where QPF picks up
again, where up to 2 inches may fall. I toyed with adding a few
counties down that way to the watch, but given the uncertainty
on where this axis ultimately ends up, elected to hand off to
the evening shift to monitor. Elsewhere, low clouds and areas of
dense fog will develop overnight.
Forcing for ascent weakens considerably Thursday morning, as
the boundary lifts back north through the area in response to
strengthening low pressure traversing through the mid and upper
MS Valley. As such expect coverage of showers to stay mainly
confined to western zones in the morning. Low clouds and fog
will lift as this pushes north with southerly winds picking up
in the afternoon. It still appears at least some sun will be
realized across a good portion of the area, especially east of
the OH River. This will boost afternoon temperatures into
record territory for the day.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 240 PM Wednesday...
As the cold front moves through, one of the questions in the
forecast process is the potential for thunder with the
associated line of showers. Took a conservative approach with
this with, but even though there is no thunder in the forecast,
some isolated embedded lightning is not out of the question.
Otherwise, the main threat continues to be any additional rain,
so will need to assess the state of the ground/waterways prior
to the convective line. This should largely be the last of the
significant rainfall with this long duration event that has
begun today before this issuance, and has a chance of becoming
snow showers with the dramatic temperature falls back into the
30s/upper 20s. No accumulations expected as this follows a
typical case here with the colder air chasing the moisture out
of the CWA. Front end of the weekend will be cold, back in a
more winter-like airmass, but dry with high pressure building
into the southern Great Lakes.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 240 PM Wednesday...
Zonal flow aloft turns southwesterly, reverting to another wet
pattern for the end of the weekend/beginning of the work week.
Another developing baroclinic boundary will set up in the
vicinity of the Ohio Valley, with indications of more low level
moisture transport into that area. Could see waves of rain
through mid week until the next upper low/surface low combo
clears out the airmass once again at the end of the extended.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
As of 155 PM Wednesday...
Radar images indicate most of the rain showers have exited east
of the mountains early this evening. Surface observations indicate
IFR/LIFR conditions across northwest sections of our CWA,
affecting PKB this evening. Latest high resolution models
suggest saturated layer from SFC through few hundred feet AGL,
will spread east to affect CKB and EKN overnight. Despite of
abundant cloud cover expected, areas of IFR/LIFR conditions
under dense fog are likely over these areas as well. This post-
rain IFR/LIFR conditions should reach CRW by 07Z, then lifting
temporarily to low MVFR after 09Z tonight.
Another period of light to moderate rain will move from the
southwest into our CWA by 03Z. Expect MVFR/IFR conditions along
the eastern mountains to prevail through at least 12Z Thursday.
This activity is associated with a second wave of energy passing
over a nearly stationary sfc boundary evident in low layered
theta-e gradient. Expect this feature to serve as the focus of
pcpn during the overnight hours into early Thursday morning.
Tonight could be a prolong period of IFR conditions areawide,
with few exceptions.
Ceilings and visibility will begin to improve into MVFR to VFR
conditions by mid morning Thursday.
Calm to light and variable winds will prevail through at least
13Z Thursday. Models suggest H850 winds become southwest,
increasing to 40-50 knots by 18Z Thursday. Expect some of these
winds to mix down under rain showers to produce gusty winds at
most places, more likely over elevations higher than 3000 feet.
Terminals should experience prevailing 5 to 12 kts gusting 20
to 25 kts mainly during the afternoon and higher elevations.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z FRIDAY...
FORECAST CONFIDENCE: High.
ALTERNATE SCENARIOS: Areas of IFR or worst under dense fog
could vary across the northern sections overnight.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 22 23 00 01 02 03 04 05 06 07 08 09
EST 1HRLY 17 18 19 20 21 22 23 00 01 02 03 04
CRW CONSISTENCY H H H H H H H H H L L L
HTS CONSISTENCY H H H H H H H M H H H L
BKW CONSISTENCY H H M H L M M M M L H H
EKN CONSISTENCY H H H H M H H L L M M M
PKB CONSISTENCY L M H H H M L M M M M M
CKB CONSISTENCY H H H M H M M M L L M M
AFTER 00Z FRIDAY...
Periods of IFR in periods of rain Thursday night.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Flood Watch through Thursday afternoon for WVZ005>011-013>020-
024>026-029.
OH...Flood Watch through Thursday afternoon for OHZ066-067-075-076-
083>087.
KY...Flood Watch through Thursday afternoon for KYZ101>103-105.
VA...None.
&&
$$
SYNOPSIS...26/30
NEAR TERM...ARJ/30
SHORT TERM...26
LONG TERM...26
AVIATION...ARJ
Area Forecast Discussion
National Weather Service Springfield MO
933 PM CST Wed Feb 6 2019
.MESOSCALE DISCUSSION...
A stationary front is currently (0330Z) lined up roughly from Jane
to Ozark, to Montauk State Park. South of this line, instability
continues to increase with additional moisture flux into the lower
trop.
RAP13, NAM, and HRRR low level cape (ML-3km) fields suggest
values increasing between 30 and 90 j/kg through the overnight
hours within a highly sheared airmass across southern Missouri.
This region will experience the better chances of organized storm
development capable of producing tornadoes, large hail, and
damaging wind gusts.
There is also a large hail risk north of the front where cape
rooted from elevated parcels will exceed 1000 j/kg through the
night.
High resolution CAMS show deep convection increasing through the
night across much of southern Missouri. This will also pose a
flash flood risk as one state route low water crossing has been
barricaded by MODOT in northern Wright County (Elk Creek at
Highway Z).
&&
.SHORT TERM...(This evening through Thursday)
Issued at 158 PM CST Wed Feb 6 2019
A strong frontal boundary remains draped from southwest to
northeast from northwestern Arkansas to around the Dent/Shannon
County line. South of the front, temperatures are in the upper 50s
and lower 60s. North of the front, temperatures are much colder
with readings still in the upper 20s from around Pittsburg, Kansas
to Warsaw, Missouri. Showers continue this afternoon mainly south
of the front in the warm sector, however areas of freezing
drizzle have persisted north of the freezing line. Areas of dense
fog also persist north of the front.
As we head into this evening, that warm front will creep north as
strong height falls begin to overspread the region. Short term and
hi res models are still struggling with the extent that the front
shifts north. Current thinking is it will nudge as far north as a
Cassville to Marshfield to Rolla line late this evening.
Meanwhile, surface low pressure will continue to deepen and slowly
swing northeast along this front. The potential for dense fog will
remain tonight to the north of the front.
Of greater concern will be significant wintry weather along with
the threat for severe storms and flooding. Starting with "warm"
side of the storm, we continue to believe that all modes of severe
weather will be possible from this evening into early Thursday
morning. Supercell and line segment convective modes will be
possible throughout the evening with a greater likelihood for
line segments as the main forcing gets into the area late tonight.
Enough MLCAPE (500-900 J/kg), deep layer shear, and low level
background helicity will exist for a supercell tornado threat.
Storms near the front will have to be watched closely as they will
tend to track right along this boundary (increasing the potential
for enhanced vorticity ingestion). The RAP model has also nudged
up significant tornado values over the last few runs, thus we are
going to maintain the threat for a strong tornado or two.
We have also expanded the potential for large hail to include
areas north of the surface front as MUCAPE values will be
sufficient to support quarter-sized hail. Any supercells in the
warm sector would have the potential to produce hail up to the
size of ping pong balls.
As for line segments, low-level shear vectors will favor
mesovortex tornadoes with anything bowing towards the east or
northeast. Additionally, damaging straight-line wind gusts will
be possible with any bowing line segments and mesovortices.
We also remain concerned with the flooding potential of creeks,
streams, and low water crossings across mainly southern Missouri.
Many locations have already seen rainfall amounts of 0.50" to
1.25". Additional rainfall amounts into early Thursday will likely
be in the 1.00" to 2.00" range.
Moving to the winter side of this storm system, short term models
have continued their trend of increasing QPF as the main upper
level support approaches. A large amount of this QPF appears to be
convective in nature. When it comes to precipitation type,
convective precipitation really throws a wrench into the forecast.
We believe that a combination of freezing rain and thunderstorms
producing sleet will be the main precipitation types as we get
into tonight. This will especially be true north of a Joplin to
Stockton to Versailles line where an Ice Storm Warning is in
effect. Expected additional ice amounts from 0.20" to 0.40" can be
expected. Additionally, sleet amounts of 0.10" to 0.25" are
expected. Given the expected thunderstorms, some localized areas
may easily exceed 0.50" of sleet. With northwest winds increasing
late tonight and Thursday morning, there is some concern for
isolated power outages.
As that low begins to swing through the Ozarks, it will drag
that cold front southeast through the Missouri Ozarks late tonight
and Thursday morning. This should result in a transition to a
light wintry mix across much of the remainder of central and
southwestern Missouri. We have therefore posted a Winter Weather
Advisory for this area with that advisory starting at 3 AM. Both
the advisory and warning are set to expire at noon on Thursday as
most precipitation should be wrapping up.
Once precipitation ends on Thursday, the main story then becomes
cold conditions. Temperatures over most areas will either be
steady or will slowly fall with high temperatures occurring in the
morning. Wind chills will actually dip into the single digits
across western Missouri and southeastern Kansas in the afternoon.
.LONG TERM...(Thursday Night through Wednesday)
Issued at 158 PM CST Wed Feb 6 2019
A cold Canadian airmass will be in the process of oozing across
the plains and into the Ozarks Thursday night and into Friday.
Morning lows Friday will bottom out in the upper single digits to
middle teens with wind chills falling from the zero mark to 10
below zero.
Clearing skies will also help allow for radiational cooling to
take place thus temperatures were knocked down a degree or two
from what models had given to start with. Another item that could
make for cooler temperatures will be any ice, snow or sleet that
accumulated through Thursday evening across the region.
The cold air will continue to make its way into the region
through the day Friday. This will keep high temperatures in the
lower 20s across central Missouri to around the freezing mark
across far southern Missouri.
Temperatures will remain cold into Saturday morning with winds
picking up somewhat which will keep morning wind chills in the
zero to 10 below range once again.
By Sunday morning, another round of precipitation will begin to
spread over the region but may be shunted south of the region
briefly early Monday morning. Models are having a hard time with
the storm system for the early to middle portion of next week.
Suffice it to say that the active weather pattern will continue
next week with periods of day time rain and night time wintry
weather through the middle of next week.
Depending on the track and strength of the systems for next week,
we could see another round of what we have currently. The
potential for severe weather and wintry weather is again a
possibility. Welcome to weather in the Ozarks.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 554 PM CST Wed Feb 6 2019
A very complex weather pattern over the region will bring
multiple flight concerns for aviators flying into the Ozarks over
the next 24 hours. Ceilings and visibilities will be predominantly
low end MVFR to IFR. A few periods of improved conditions will
occur but will be short lived. Weather ranging from thunderstorms
with hail to dense fog to freezing rain will make the flight
conditions difficult over the area. A cold front will begin to
clear out the region, but not until after 18z Thursday.
Additionally, a very strong low level jet will bring low level
wind shear and gusty surface winds to the area after sunrise
Thursday as well.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...Flood Watch through Thursday afternoon for MOZ082-083-090>098-
101>106.
Dense Fog Advisory until 3 AM CST Thursday for MOZ057-058-
069>071-079>083-088>098-101>106.
Winter Weather Advisory from 3 AM to noon CST Thursday for
MOZ057-058-069>071-079>081-089>095-101>103.
Ice Storm Warning until noon CST Thursday for MOZ055-056-066>068-
077-078-088.
KS...Dense Fog Advisory until 3 AM CST Thursday for KSZ101.
Ice Storm Warning until noon CST Thursday for KSZ073-097-101.
&&
$$
MESOSCALE...Cramer
SHORT TERM...Schaumann
LONG TERM...Hatch
AVIATION...Hatch
Area Forecast Discussion
National Weather Service San Angelo TX
552 PM CST Wed Feb 6 2019
.AVIATION...
/00Z TAFS/
Currently, we have VFR conditions across the area with gusty
southwest winds. Scattered showers and thunderstorms are expected
to move into the area within the next few hours, continuing
through midnight tonight before a Pacific cold front moves
through, pushing the activity east and out of the area by 09Z or
10Z. Will continue to carry either VCTS or TEMPO groups for
thunderstorms tonight. West to northwest winds will follow the
front, increasing to 15 to 25 knots by mid morning Thursday. A
second front will move south through the area tomorrow, but likely
only make it through the KABI area before the end of this TAF
forecast. 20
&&
.PREV DISCUSSION... /issued 302 PM CST Wed Feb 6 2019/
SHORT TERM...
(Tonight through Friday)
A spring-like day continues across West Central Texas this
afternoon, with temperatures in the 70s and dewpoints in the 50s
and 60s for most locations. A Pacific front is still set to move
into the area this evening with showers and storms developing
ahead of the boundary. Latest HRRR and TTU WRF show convection
developing mainly east of an Abilene to San Angelo line by mid
evening, and then spreading east and out of the Heartland and Hill
Country before sunrise. Will continue the highest PoPs to the
east with decreasing chances across the western Concho Valley and
Big Country.
Drier and cooler conditions for Thursday for most areas, with
highs mainly in the 50s. The arctic front that has been sitting
across the Red River today will surge south as well, reaching the
northern Big Country before noon and moving across the rest of the
area by late afternoon. This will bring the coldest air mass to
the area, with lows dropping well into the 20s for most of West
Central Texas by Friday morning. Wind chills will be even colder,
dropping into the teens. Low level moisture will be scarce, but
models suggest mid level moisture will rapidly increase as
overrunning begins to become established. GFS and ECMWF show a
little precip developing across the southeast counties, east of a
Brownwood to Brady to Junction line. Model soundings actually
suggest that snow will be developing aloft and melting as it
reached the ground, perhaps even reaching the ground in those
areas where the precip is heavy enough to wet bulb temperatures
down far enough. Suspect that the rain will be light enough to
keep most areas as rain, but will add a mention of rain/snow mix
as a possibility.
LONG TERM...
(Friday night through Wednesday)
A few sprinkles possible Friday evening...in Brown and Saba
counties. Confidence is low, however, as most of the models
indicate dry air in the low levels and most/if any precipitation
would evaporate before hitting the ground. A few flurries could
also mix in as temperatures aloft will be below freezing.
There is a chance of showers Saturday night into Tuesday Monday
as surface high pressure moves east, allowing low and mid level
moisture to return to the region. Rainfall amounts will be
generally light each day. A warming trend will continue with highs
in the lower to mid 40s Saturday to upper 50s/lower 60s Sunday
and mid/upper 60s Monday.
Rain chances end Tuesday night as an upper through/low moves
across Oklahoma and Kansas, bringing drier and more stable air
into West Central Texas. It will be slightly cooler with highs in
the lower 60s.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 47 55 24 39 / 50 0 0 5
San Angelo 48 60 26 39 / 40 0 0 10
Junction 52 65 30 39 / 50 10 0 30
Brownwood 50 61 27 39 / 70 5 0 20
Sweetwater 44 56 24 39 / 30 0 0 5
Ozona 46 60 29 41 / 30 0 0 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Tulsa OK
955 PM CST Wed Feb 6 2019
.DISCUSSION...
Widespread convection continues from the Tulsa area to the north
at this time, with a few cells producing small hail and wind
gusts to around 40 mph. Freezing temperatures likely resulting in
substantial ice accumulations across northern half of Osage and
extreme northern Washington Co as evidenced in loss of mesonet
wind data. This current cluster of storms will be moving out of
that area within the next hour, but the recent model trends have
additional convection moving into northeast OK after 06z with
potential for at least local ice accum greater than 1/4 inch.
Drier air will eventually push south across the area late tonight
but not before temperatures coll enough for a transition to
freezing rain across a large portion of eastern OK and extreme
northwest AR. Existing winter weather advisory should cover it,
but a quick upgrade to ice storm warning is not out of the
question to the northwest of Tulsa if convective trends upstream
over the next few hours warrant it.
Overall thinking regarding severe weather potential elsewhere
tonight has not changed much, as increasing warm advection will
force additional storms near and south of the frontal zone. Along
and south of the boundary which lies across extreme southeast OK
there remains at least some potential for sfc-based updrafts and
low tornado potential overnight.
Finally, have canceled much of the dense fog advisory as vsbys
have mostly improved to 2SM or greater. The exception remains
some areas to the SW of Tulsa which could still see greatly reduce
vis through midnight.
&&
.PREV DISCUSSION... /Issued 544 PM CST Wed Feb 6 2019/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
LIFR conditions will continue at the Oklahoma sites until late
tonight, with gradual improvement then expected into Thursday,
with VFR conditions returning by late Thursday. Initially VFR
conditions at the Arkansas sites will worsen to MVFR overnight,
and remain MVFR through much of Thursday. Scattered showers and
thunderstorms this evening will become more numerous overnight,
before ending from the west late tonight and early Thursday. Some
freezing rain will likely occur at the Oklahoma sites before the
precipitation ends. Northwest winds will gust to over 20 knots at
times during the day Thursday.
PREV DISCUSSION... /Issued 426 PM CST Wed Feb 6 2019/
DISCUSSION...
Yet another very busy day on the forecast desk. This is what
happens when you have a shallow arctic airmass wedged into your
area, with a moist Gulf airmass to its south.
Models today have trended more aggressive with elevated convective
development on the cold side of the front tonight into Thursday
morning, and this has increased qpf on the cold side of the
southeastward advancing freezing line with time. Thus, have
increased ice amounts across northeast Oklahoma and far northwest
Arkansas and have expanded the winter weather advisory. Portions
of far northeast Oklahoma near the Kansas border could pick up
between a tenth and 2 tenths of an inch of icing, while other
areas could accumulate up to a tenth of an inch. Combine the
heavier icing potential near the KS border with increasing
northwest winds behind the advancing arctic front tonight, and
there could be some scattered power outages.
In between the freezing line and the front sitting over southeast
Oklahoma into central Arkansas, areas of dense fog will persist
into the evening, reducing vsbys down to a quarter mile or less. A
dense fog advisory has been issued thru midnight tonight.
Now to the convective forecast. Hi-res data earlier today
suggested there was a low probability of supercells near/along the
front this afternoon. So far, this has not occurred. As mentioned
earlier, the trends in the data suggest more development north of
the front tonight compared to previous data. Local model and HRRR
continue to show some UH tracks with some of the storms,
suggesting that a large hail threat exists. If any storms can
develop closer to the front and are more surface based, there
would be a low tornado threat as well. The scenario of a robust
convective line with the front is not suggested as much today,
mainly because the shallow front remains wedged pretty far south
in our area today. All of the activity should be east of the
region by 6 am.
After some quiet days Friday and Saturday, the next precip event
will begin Saturday night into Sunday when the warm conveyor
precip spreads northeast ahead of the next storm system. Again,
it is possible that areas of northwest Arkansas will be near
freezing when the rain moves in from the southwest, so a continued
mention of light icing continues with this forecast. The main
upper system will affect the area Monday night into Tuesday. Based
on the track of the system, winter weather impact potential
doesn`t look all that high attm. Some light snow accums are
possible on the back side of the system before it moves east.
Lacy
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 25 29 12 34 / 90 10 0 0
FSM 38 38 18 40 / 100 70 0 0
MLC 31 33 16 38 / 100 30 0 0
BVO 23 27 10 33 / 90 0 0 0
FYV 31 34 10 33 / 100 70 0 0
BYV 42 46 12 31 / 100 80 0 0
MKO 30 30 15 36 / 100 30 0 0
MIO 25 27 10 31 / 100 30 0 0
F10 27 30 15 37 / 90 20 0 0
HHW 49 55 21 45 / 100 60 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...Winter Weather Advisory until 9 AM CST Thursday for OKZ058-
060>072.
Dense Fog Advisory until midnight CST tonight for OKZ060-064>066.
Winter Weather Advisory until 6 AM CST Thursday for OKZ054>057-
059.
AR...Winter Weather Advisory until 9 AM CST Thursday for ARZ001-010.
&&
$$
SHORT TERM...14