Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 02/09/19
AREA FORECAST DISCUSSION
National Weather Service Albany NY
947 PM EST Fri Feb 8 2019
.SYNOPSIS...
Colder and blustery conditions across the area with some
lake effect snows impacting portions of the western Adirondacks and
western Mohawk Valley overnight into Saturday morning. Saturday
night and Sunday will feature seasonably cold temperatures and fair
weather with high pressure building in.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A Wind Advisory remains in effect for the eastern New York
excluding the mid Hudson Valley, and for all of western New
England until 3 pm Saturday.
A Winter Weather Advisory remains in effect until 1 pm Saturday
for Herkimer County.
As of 945 PM EST....
A second cold or arctic front continues to move southeast from
northern NY and the St. Lawrence River Valley. This boundary is
helping to steer the lake effect snow band southward across the
western and southern Adirondacks, and into the Lake George
Region. We issued an SPS for a brief burst of snow over
northern Warren and Washington Counties based on the local and
regional radar. The latest 3-km NAMnest and HRRR show the
eastern portion of this band dying as it presses southward over
the next hour or so. The lake effect should keep going over
southern and central Herkimer County with 2 to 6 inches
possible. Perhaps 2 to 4 inches over southwest Hamilton. An inch
or two over western Fulton and Montgomery Counties. The flow
continues to veer to the northwest with the downstream extension
weakening.
The shifting/veering boundary layer flow will limit snow
accumulations; indications are the greatest snow amounts will
occur north of Interstate 90 northward to the vicinity of Route
365 and Route 8. We have expanded some slight and chance pops
extending eastward across the northern and central portions of
our forecast area into the Capital Region and southern Vermont
for snow showers and then the focus is more in the Mohawk
Valley overnight.
We are getting some snow flurries and snow showers over the
Capital Region and northern Catskills off of Lake Erie currently.
We are not expecting too much accumulation from these. Maybe a
dusting at best blowing around in the wind. In terms of the
winds, we are expecting the winds to increase a bit between
midnight and 6 am with strong west to northwest winds of 15 to
30 mph with some gusts in the 40-50 mph due to the strong H925
winds of 35-45 kts down the Mohawk Valley on the NAM, and some
mixing from 1-2 kft AGL of 35-45 kts or so. The Wind Advisory
continues overnight. These wind gusts could cause downed limbs,
trees, and power lines resulting in isolated to scattered power
outages.
Temperatures will continue to fall and are expected to bottom
out from the single digits to upper teens across the region with
the gusty winds. Wind chills will be in the single digits to
below zero.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
Lake effect snows are expected to retreat and diminish Saturday
morning as ridging builds in at the surface and heights aloft
begin to rise all disrupting the favorable flow. Expecting
increasing sunshine with seasonably cold temperatures. Winds
will remain strong especially in the morning. Expecting highs
from the teens to lower 30s, however the winds will make it feel
much colder. Even colder Saturday night as ridging moves into
the region with lows expected to drop to around zero in portions
of the southern Adirondacks to the lower teens in the mid Hudson
Valley. Good news winds will weak becoming light overnight.
The surface ridge is expected to crest over the area Sunday as
it weakens through the day. Clouds will be in the increase with
nearly zonal flow aloft with some weak impulses moving through
the fast flow. There are slight to low chances for some snow
showers Sunday night however moisture and support is rather
limited. Fair weather is expected Monday as ridging aloft builds.
Seasonal temperatures and light winds are expected Sunday through
Monday. Highs both days mainly from the upper teens to mid 30s
and lows Sunday night from single digits to near 20 degrees.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
Focus in the long term will be on the potential for accumulating
snow and perhaps a wintry mix Tuesday into Tuesday night. Ridging
aloft and at the surface Monday night will ensure a tranquil night,
however it will be somewhat cold given northerly flow draining from
the high centered to our north. The ridging will quickly give way to
an approaching negatively-tilted trough which may close off over the
western Great Lakes by late Tuesday or Tuesday night. Models differ
with the strength of this trough/upper low, which is not too
surprising at this time scale, but there is generally good consensus
in the overall pattern. The primary surface low is expected to be
well to our west during this timeframe over the western Great Lakes
and southeastern Ontario, but guidance is suggesting a weaker
secondary low may develop from roughly the Jersey Shore to Cape Cod.
Often this double-barrel low structure can result in a relative
minimum in precipitation in our area if the secondary low does not
strengthen until it is off to our east. However, this system appears
to entrain a good deal of Gulf/Atlantic moisture, so confidence is
high in measurable precipitation Tuesday into Tuesday night.
Specific impacts remain to be seen, but there is decent potential
for impactful winter weather during this time. Will mention this
system in the Hazardous Weather Outlook. As far as p-type, model
consensus supports snow at the onset much of Tuesday, possibly
transitioning to a wintry mix with sleet and freezing rain Tuesday
night as persistent warm advection aloft continues.
Drier midlevel air should arrive by Wednesday but there may be a few
remaining showers. Surface temperatures could spike into the 30s and
40s as cold advection aloft mixes out the inversion. It looks rather
breezy as well. Temps do not appear to get terribly cold in the wake
of this system, and midlevel heights are expected to rise again
quickly Wednesday into Thursday. For now it appears mainly dry
Wednesday night into Thursday, but there are signs that another deep
trough will approach by Friday with potentially another round of
widespread precipitation
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
A secondary cold front will move across eastern NY and western
New England tonight. A strong sfc pressure gradient will
continue Saturday morning into the afternoon between high
pressure building from Great Lakes Region and low pressure over
the Canadian Maritimes producing windy conditions. The winds
will gradually subside Saturday night.
The main issue will continue to be windy conditions tonight into
tomorrow for KGFL/KALB/KPOU/KPSF.
The skies will go from scattered to broken, then broken to
overcast from KALB/KPSF northward early this evening with the
approach of the secondary cold front and some lake effect
moisture. Cigs should remain VFR in the 4-6 kft AGL. Further
south towards KPOU just some scattered clouds will be around.
The winds will be from the west generally at 10-20 kts with
some gusts in the 25-35 kt range with the higher gusts at
KALB/KPSF.
The front moves across the region between 06Z-10Z with perhaps
some snow showers getting into KALB/KGFL/KPSF in the 05Z-09Z
time frame. Brief reductions to MVFR conditions are possible in
any snow showers. The winds will shift more to the west to
northwest at 15-25 kts with some gusts around 40 kts at
KALB/KPSF. These strong winds will persist into the mid to late
morning. We linger them the longest at KALB/KPSF...and lowered
the gusts to 25-30 kts at KGFL/KPOU. Flight conditions will be
VFR after sunrise with just a few cumulus or few-sct cirrus
around.
Expect the winds to begin decrease between 18Z-21Z/SAT from the
northwest at 10-15 kts with still a few gusts around 25-30 kts
or so at KALB/KPSF. Mostly clear skies and VFR conditions will
continue to the end of the TAF cycle.
Outlook...
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: Low Operational Impact. Slight Chance of SHSN.
Monday: No Operational Impact. NO SIG WX.
Monday Night: Low Operational Impact. Slight Chance of SN.
Tuesday: High Operational Impact. Definite SN.
Tuesday Night: High Operational Impact. Definite SN...SLEET.
Wednesday: Moderate Operational Impact. Chance of SHRA...SHSN.
&&
.HYDROLOGY...
Areal flood warnings have been issued for flooding along the
Kayaderosseras Creek due to an ice jam in Ballston Spa and for
flooding along the Mohawk River impacting the lower elevations
along Route 5 and Route 5S resulting in road closures in
Rotterdam and Rotterdam Junction.
Based on local river gauges some rivers have crested and others
will crest this evening. With temperatures dropping to well
below freezing tonight any continuing runoff will end. Outside
lake effect snows mainly dry weather is expected into Monday
night.
For details on specific area rivers and lakes, including
observed and forecast river stages and lake elevations, please
visit the Advanced Hydrologic Prediction Service /AHPS/ graphs
on our website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...Wind Advisory until 3 PM EST Saturday for CTZ001-013.
NY...Wind Advisory until 3 PM EST Saturday for NYZ032-033-038>043-
047>054-058-061-063-066-082>084.
Winter Weather Advisory until 1 PM EST Saturday for NYZ032-038.
MA...Wind Advisory until 3 PM EST Saturday for MAZ001-025.
VT...Wind Advisory until 3 PM EST Saturday for VTZ013>015.
&&
$$
SYNOPSIS...IAA/Wasula
NEAR TERM...IAA/Wasula
SHORT TERM...IAA
LONG TERM...Thompson
AVIATION...Wasula
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
National Weather Service Binghamton NY
832 PM EST Fri Feb 8 2019
.SYNOPSIS...
A weak cold front will push south into the region tonight with
some lake effect snow in the typically favored locations that
lasts into Saturday. For Sunday and Monday, high pressure will
build in them move through the area. A low pressure system will
move northeast into the region on Tuesday bringing the next
chance of precipitation.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
830 PM UPDATE...
Mesoscale models have consistently been to far north with the
placement of the Ontario band. Radar mosaic does show the band
beginning to drift south now so have delayed the onset of the
snow in the hourly wx grids and in the TAFs. Otherwise, grids
are generally in good shape with only minor adjustments need at
this time.
Previous discussion below.
A weak cold front will push southwest into the region tonight.
However, the winds will still be out of the west to west
northwest given the strength of the system that moved through
today. Our two main weather concerns are the wind and lake
effect snow potential as a result.
For the wind, wind gusts from 30 to over 45 mph have been
observed. Short range modeling such as the HRRR and a look at
Bufkit soundings do show the potential for top gusts to increase
a bit in portions of the Finger Lakes, NY Thruway and Southern
Catskills areas in NY with some gusts around 50 mph. These
gusts may bring down some trees and wires locally, so the wind
advisory will continue into the day Saturday for these
locations. The advisory was also expanded further south from
portions of the Finger Lakes eastward to Cortland county with
this forecast update. Winds will decrease gradually during the
day Saturday as the pressure gradient relaxes but it will still
be gusty with some 25 to 35 mph gusts in the morning.
As for the lake effect snow potential, Preference went toward
the HRRR, NAM-nest and RGEM models for QPF and location of the
main band of snow tonight into Saturday morning. This band
should gradually develop through the early evening with the loss
of instability which is causing a more cellular look on radar
currently with the snow. Model agreement is fairly good on the
overall setup that this band starts off in northern Oneida
county then very slowly move south to around Syracuse for a time
overnight. The band then diminishes to snow flurries and
showers in the morning. A very tight gradient is expected with
snowfall amounts with the highest amounts from 6-8 inches in
western Oneida county and little to snow just south of Syracuse.
While the winds will be high and travel impacted due to blowing
and drifting snow we are not expecting to meet the visibility
criteria of 1/4 mile needed for a blizzard headline. Headlines
will be maintained with a winter storm warning for NW Oneida
county and advisories further south.
Lows tonight should fall into the 10`s tonight with only a
rebound into the 20`s due to the cold air advection. While
clear, the airmass will modify some only sending temperatures
back down into the 10`s.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
Sunday will be fair and cool before snow showers spread into
the forecast area Sunday night into early Monday. A dusting to
an inch of new snow accumulation is expected. Temperatures will
fall into the upper-teens and lower-20s.
Temperatures will rebound on Monday into the lower or middle-30s
ahead of the next approaching storm system.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A rapidly strengthening stacked low pressure system will rotate
into the Ohio Valley and Great Lakes Monday night into Tuesday.
This cyclone will push a warm front across NY and PA initially.
Snow is forecast to fall Monday night into Tuesday.
An included front will transport warmer air into our region
Tuesday night. The models suggest a mix of snow, sleet, and
freezing rain will result, though our far southern counties
might change over to rain if enough warm air advances into PA.
The storm will finish on Wednesday with a mix of snow and rain
before tapering off late in the day.
The lakes will become active behind the front on Thursday with
scattered snow showers, mainly over Upstate NY.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
A westerly flow of dry air will bring mostly VFR conditions to
the TAF sites this period. Exception will be at SYR and RME
where lake effect snow showers will bring IFR restrictions
beginning this evening and continuing for much of the night.
The band will weaken and move northward on Saturday returning
all stations to VFR. A tight pressure gradient will keep gusty
WNW winds through the period.
Outlook...
Saturday afternoon... Any restrictions from lake effect snow
showers and flurries lifting to VFR. Northwesterly wind gusts
from 15 to 30 knots decreasing throughout the afternoon.
Saturday night through Sunday....VFR.
Sunday night through Monday... VFR with a few snow showers
around which could cause brief visibility reductions Sunday
night.
Monday night through Wednesday... MVFR and IFR with snow
developing Monday night then potentially changing to a wintry
mix on Tuesday. Low ceilings likely to persist into Wednesday.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...Wind Advisory until 1 PM EST Saturday for NYZ009-015>018-022-
023-025-036-037-044>046-057.
Winter Storm Warning until 1 PM EST Saturday for NYZ009.
Winter Weather Advisory until 1 PM EST Saturday for NYZ018-036-
037.
&&
$$
SYNOPSIS...DGM/MWG
NEAR TERM...DGM/MWG
SHORT TERM...DJP
LONG TERM...DJP
AVIATION...DGM/MWG
Area Forecast Discussion
National Weather Service Columbia SC
1026 PM EST Fri Feb 8 2019
.SYNOPSIS...
In the wake of a cold front moving off the coast this evening
Canadian high pressure will build into the region from the
north over the weekend. Rain chances return Sunday through
Monday as moisture overruns a stalled front to our south.
Another cold front will cross the area late Tuesday.
&&
.NEAR TERM /UNTIL 7 AM SATURDAY MORNING/...
Cold advection continues across the area this evening as the
cold front pushes offshore. Satellite imagery shows a blanket
of higher cirrus continues to be over the forecast area and
is expected to remain overnight. Temperatures will continue to
fall overnight with little radiational cooling due to the cold
advection keeping the boundary layer mixed. Overnight lows
expected in the mid 30s northern Midlands to upper 30s to around
40 degrees in the southeast Midlands and lower CSRA.
Cool air advection over warmer lake water temps could provide
wind gusts around 25 kt over area lakes tonight, mainly towards
the southeast Midlands and will continue the Lake Wind Advisory
for Lake Marion beginning later tonight.
&&
.SHORT TERM /7 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
Saturday, high pressure will ridge into the Southeast bringing
cool, dry air into the forecast area. The right entrance region
of an upper level jet will be over the forecast area much of
the day providing synoptic scale ascent and mostly cloudy skies
through the afternoon. Given the cold advection and cloud
coverage, daytime temperatures will be below or near normal with
highs from the upper 40s north and mid 50s south. An upper
level shortwave will move over the area Saturday morning. The
HRRR and a few other Hi-Res models indicate some shower
development associated with the shortwave. It is possible that
the PVA and synoptic scale lift may allow a few weak showers to
develop. Although with mid and low level dry air (PWAT values
less than 0.5 inches) it is very unlikely that any measurable
rainfall will occur.
Saturday night, high pressure shifts offshore allowing 850mb
moisture advection to increase across the Deep South. Cloud
coverage will increase before or around sunrise shutting down
radiational cooling across the southern part of the forecast
area. Expect lows in the mid to upper 30s in the CSRA to around
30 degrees in the northern Midlands. Moisture continues to be
shallow up to sunrise, making rainfall unlikely. Although it is
not out of the question that there may be some showers moving
into the CSRA around sunrise with PWAT values increasing to near
1 inch.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
Sunday, the chance for rainfall returns as warm, moist air is
lifted over a surface ridge along the mid-Atlantic states. Cool
air ridging in from the north with overrunning moisture
advection and potential for light precip suggests that
temperatures will remain cool throughout the day.
The chance for rain will continue through the early part of
next week ahead of another approaching frontal system. A cold
front is expected to pass through the area Tuesday or Tuesday
night. Models indicate strong mid-level moisture advection,
synoptic scale lift and strong warm advection ahead of the
front. This suggests that gusty winds and showers will be likely
Tuesday with the possibility of some thunderstorms depending on
the timing of the frontal passage. Dry weather will briefly
return mid-week while we are between systems. The next frontal
system will impact the Southeast late next week. Temperatures
will show a warming trend from Sunday to Tuesday ahead of the
first front with near normal temperatures expected for the
remainder of the period.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
High confidence for VFR.
Surface high pressure will build into the area from the north,
bringing cold and dry air in the low levels. Southwest flow
aloft will keep high level clouds over the TAF sites. North to
Northwest winds at the start of the TAF period will veer
Northeast overnight. As surface speeds drop, model data
indicates potential for a 25-35 knot low-level jet to form.
Current VAD winds on radar do not indicate LLWS at 03Z, but
LLWS potential may be included in the 06Z TAF package. No
precipitation nor fog is expected due to low level dry air.
EXTENDED AVIATION OUTLOOK...CIG restrictions expected Saturday
night through Monday. Light rain expected Sunday through Monday
in a surface wedge pattern. Continued restrictions possible,
and chance of showers, Tue/Tue nt associated with a cold frontal
passage.
&&
.CLIMATE...
A record high temperature of 77 degrees was set at the Columbia
Metro Airport. This breaks the previous record of 76 set in
1965. Temperature records for the Columbia Metro Airport date
back to 1948.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...Lake Wind Advisory until 4 PM EST Saturday for SCZ031-036>038.
&&
$$
Area Forecast Discussion
National Weather Service Indianapolis IN
1004 PM EST Fri Feb 8 2019
.UPDATE...
The Aviation section has been updated below.
&&
.SYNOPSIS...
Issued at 300 PM EST Fri Feb 8 2019
Arctic high pressure over the plains states will push east across
the Ohio Valley tonight through Saturday Night. This will result
in dry but very cold weather across central Indiana through
Saturday Night.
The high pressure system will depart to the east of Indiana by
Sunday...allowing an upper level weather disturbance to push into
the area from the southwest. This will result in chances for snow
with some light accumulations returning to Central Indiana.
Two more upper level weather disturbances are expected to pass
across the Ohio Valley on Monday and again on Tuesday. This will
result in more chances for rain then along with moderating
temperatures.
Even more precipitation will be possible late next work week.
&&
.NEAR TERM /Tonight/...
Issued at 955 PM EST Fri Feb 8 2019
Raised min temps a few degrees per obs trends and latest hourly
guidance from the HRRR and LAMP. Remainder of forecast in fine
shape. Previous discussion follows.
Issued at 300 PM EST Fri Feb 8 2019
Surface analysis early this afternoon shows strong high pressure
in place across the Plains states...centered over northern
Missouri. Cold NW flow was in place across Indiana with GOES16
showing just scattered cu across the forecast area. Temps had
fallen to the teens across central Indiana.
GFS and NAM suggest weak ridging aloft tonight with slight lee
side subsidence in place across the Ohio Valley. Mid level
ridging to the west and subsidence is more impressive. Forecast
soundings shows a very dry column across area tonight. Meanwhile
at the surface...the high pressure system is expected to build
east to Indiana. This will result in clear skies and cold temps
overnight. With light winds will trend lows at or below the
forecast builder blends.
&&
.SHORT TERM /Saturday through Monday/...
Issued at 300 PM EST Fri Feb 8 2019
GFS and NAM continue to suggest surface high pressure still in
place across Indiana on Saturday...drifting east to the
appalachians on late Saturday night. No upper support is present
and forecast soundings reveal the continued dry column in place
which should lead to just dry weather through Saturday night.
Warm air advection will be in play on Saturday and Saturday night
mainly due to the coldest of the cold air departing eastward.
Thus will again trend toward a partly cloudy sky and trend
temperatures close to the forecast builder blends.
GFS and NAM suggest a strong short wave approaching the Ohio
valley on Sunday. Strong upper support is available. Forecast
soundings indicate a top down saturation on Sunday with the
column remaining below freezing. Thus most of the precip at this
time looks to be in the form of snow. With pwats near 0.60 to
0.75...accumulating light snows will be possible through Sunday
evening. Further strong support is seen on the 290K GFS Isentropic
surface...showing good up glide and specific humidities over 4
g/kg. Thus will trend pops at or above the forecast builder blends
and trend highs cooler and lows warmer given the expected
precipitation.
Active weather looks to persist on Monday through Tuesday the GFS
continue to indicate a strong SW flow in place aloft with several
short waves embedded within the flow streaming into the Ohio
Valley. Warm air flowing into the Ohio Valley allows forecast
sounding to rise above freezing on Monday...allowing the ptype to
switch to rain. This will persist through Tuesday as SW flow will
remain in place through that time. Meanwhile at the surface a warm
front is poised to set up once again across the Ohio Valley as
the forcing dynamics pass aloft through Tuesday. Similar to the
previous system from Wed-Thur...the models suggest a stronger
upper wave and low pressure system to push toward Michigan once
again on Tuesday. For now...forecast soundings show good
saturation on Tuesday with pwats near 0.8 inches...thus confidence
for rain during this period will be high. Again will trend highs
at or above the blend on Monday and Tuesday...trending lows warmer
than the blends...but sticking close to the blends highs given
the expected rain.
&&
.LONG TERM /Monday Night through Friday/...
Issued at 353 PM EST Fri Feb 8 2019
The extended period begins with the forecast area under the
influence of southwest flow aloft with an approaching upper level
storm system from the High Plains area. There is also a frontal
boundary near the Ohio River as the period begins. The surface low
pressure associated with this system moves northeast through the
Plains states Monday night...bringing the best chance for
precipitation early Tuesday morning across all of the forecast
area. Even with temperatures near freezing across northern zones
Monday night into Tuesday morning...there is a pronounced warm
nose at or about 2-3000 ft up. This will look to keep much of the
precipitation during that timeframe as rain. If surface
temperatures were to dip to freezing or below...we could be
looking at freezing rain. This will bear some watching. The cold
front associated with the system moves through on Thursday turning
winds to out of the southwest then the west. Cooler air arrives by
Tuesday evening...transitioning any remaining precip across the
area from light rain to light snow Tuesday night. High pressure
filters in briefly for Wednesday through Thursday morning before
impact from the next approaching system is felt on Thursday
afternoon/evening. The bulk of the precipitation looks to fall as
rain until the surface low passes across the forecast area Friday
afternoon/evening and winds turn to out of the west-northwest
ushering colder air into the area. Snowfall looks to be light.
&&
.AVIATION /Discussion for the 09/06Z TAFs/...
Issued at 1004 PM EST Fri Feb 8 2019
VFR through the period.
Clear skies expected most of the period, although some lingering
stratocumulus around 3kft may still be at BMG early in the period.
Should be FEW-SCT at most.
Winds early in the period will be from 310-340 at about
5-10KT, with perhaps a lingering gust into the teens, steadily
decreasing overnight to less than 10KT from about 070-080 by mid
morning.
No obstructions to visibility expected during the period.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...Puma
NEAR TERM...Puma/Nield
SHORT TERM...Puma
LONG TERM...MRD
AVIATION...Nield
Area Forecast Discussion
National Weather Service Shreveport LA
1002 PM CST Fri Feb 8 2019
.UPDATE...
Remove Northern Co/Pa from the Winter Weather Advisory and clear
some pops North as well.
&&
.SHORT TERM.../Tonight/
Air temperatures remain around the freezing mark in E TX along and
South of I-20. While Shreveport remains in the mid 30s and liquid,
but a good sleet burst could drop it a couple of degrees in a
hurry. Radar is showing a long streak of Pacific moisture over the
heart of the ArkLaTex that extends way back into central TX.
Farther East along I-20 in N LA, the temp is 33 and will see the
last of this activity by around daybreak likely below freezing.
The HRRR shows a progression of motion to the ESE out of the area
by around daybreak. We will run the zones again at midnight due to
precip type changes during the evening. /24/
&&
.PREV DISCUSSION... /issued 657 PM CST Fri Feb 8 2019/
AVIATION...
For the ArkLaTex, a streak of tropical moisture overrunning cold
air on the sfc and low to mid levels. Sfc reports vary from -ra to
ip/sn. Ground temps are too warm to present a long term problem,
but a burst could slow things down in isolated areas for hours.
Sfc winds are light N/NE and 10-25KT extending up to 5kft, then
back around to W/SW in the mid levels with SW flow from 30-100KT
by FL300. Icing danger aloft likely abv dry pocket above 10kft.
Our balloon saw abundant moisture existing below frz b/t 10-20kft.
/24/
PREV DISCUSSION... /issued 518 PM CST Fri Feb 8 2019/
SHORT TERM /Tonight through Saturday Night...
Temperatures continue to trend colder than guidance this afternoon
and observations are now beginning to show a mix of snow and
sleet which mixing in with rain in East Texas and northern
Louisiana this afternoon. With the support of the radar/temp
trends along with reports from Jacksonville, Texas and other
reports further upstream, a Winter Weather Advisory has been
issued through 9:00 a.m. on Saturday morning.
For this evening and tonight, the key message is that elevated
surfaces like bridges and overpasses will become icy as light
sleet and snow accumulate. At 10a this morning, the latest ground
temp observation from the Shreveport office was 46F, down 4
degrees from 50F at midnight. The latest high resolution model
runs of the HRRR and 3km NAM support the current forecast of a
wintry mix across Deep East Texas spreading eastward into
northern Louisiana through midnight. Analyzing RAP280-290K
isentropic uplift, although the thermal layer becomes more
saturated, forcing appears strong enough to support scattered
showers with a wintry mix overnight. Overnight lows will range
from the upper 20s in SE Oklahoma and SW Arkansas to the lower 30s
southward into Deep East Texas and northern Louisiana.
Any accumulations should melt during the day Saturday as
temperatures warm back into the 40s across the entire area. More
scattered showers will become possible by late Saturday afternoon
into Saturday night across our westernmost counties of East Texas
as low-level warm air advection and isentropic ascent begins to
increase once again while abundant moisture is supplied by the
southwesterly flow aloft. Lows on Saturday night will range from
the mid 30s across southeastern Oklahoma and southwestern Arkansas
to the lower 40s in portions of northern Louisiana. /04/
LONG TERM /Sunday through Thursday Night...
As high pressure moves east and low pressure begins to develop over
the central plains, a deep sw flow will bring moisture quickly back
into area. Rain chances will initially be focused to the south and
east of this low, on a quasi stnry warm frontal boundary, but will
begin to slowly spread further into the region. As this front moves
across region as a cold front, will see rain chances late Monday
night and Tuesday shifting from nw to se before ending around
Tuesday eve.
Overrunning rains will quickly return to the area late
Wednesday to early Thursday coinciding with a warming trend
underway. A weak front may push the moisture east of the area by the
wknd, which is just beyond the end of the current fcst
period. /07/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 31 43 40 57 / 60 10 20 30
MLU 30 45 41 60 / 60 20 10 20
DEQ 28 40 35 44 / 10 10 60 80
TXK 28 41 37 48 / 20 10 50 60
ELD 28 44 38 54 / 30 20 30 40
TYR 32 40 38 53 / 70 20 40 60
GGG 32 42 40 56 / 70 10 30 40
LFK 34 42 40 64 / 70 20 20 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...Winter Weather Advisory until 9 AM CST Saturday for LAZ001>006-
010>014-017>022.
OK...None.
TX...Winter Weather Advisory until 9 AM CST Saturday for TXZ126-
136>138-149>153-165>167.
&&
$$
24/04/07