Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/11/19
Area Forecast Discussion
National Weather Service La Crosse WI
639 PM CDT Wed Apr 10 2019
.SHORT TERM...(Tonight through Friday)
Issued at 310 PM CDT Wed Apr 10 2019
Potent spring storm bringing a variety of impactful weather to the
region tonight through Thursday. What you see depends on where you
live.
SNOW: strong frontogenetically forced band of mainly snow moving
slowly north/northeast - currently running from central MN into
southeast WI per radar imagery. Meso models continue to shift this
band north, taking on a more west-east orientation while enhancing
the forcing. Ice in cloud/cloud temps enough that snow should be the
main (if not only) pcpn type assocaited with the heavy pcpn, and
thus results in a few more inches north of I-94 then previous
thought. Currently, 6 to 8 (locally 10) additional inches are
expected in those areas - and will issue a Winter Storm Warning to
cover the related impacts.
To the south, a narrower band of accumulating snows (1-4") still
look likely, but will quickly give way to rain/wintry mix. Strong
warming a loft and potential for loss of ice outside of the main
pcpn bands keep freezing pcpn in the picture. Sfc temps could be
border line for freezing, with better chances on elevated/cold sfcs.
The bulk of the accumulating snows/wintry mix will be done Thu
morning.
WIND: tight pressure gradient with low level winds as much as 70 kts
by 2 kft tomorrow morning (per RAP soundings - perhaps a bit
overdone). Mix down potential hampered by relatively stable near sfc
layer, but soundings still suggest 30 to 40 kt gusts will be common.
With this in mind, will issue a Wind Advisory for locations not
already covered by Winter Warnings/Advisories - tonight and Thu
morning. Will cover the wind impacts with pcpn threats in the north.
STORMS: As the storm system lifts northeast Thu, the sfc low is
still progged to hang mostly west of the forecast area. Associated
warm front lifts across eastern IA/Il with the meso models sparking
showers/storms along and north of it. Instability this far north is
meager to nil (long and skinny per bufkit soundings), but wind shear
is impressive - a silly 85 kts for 0-6km. Would need an awful lot of
instability to balance that kind of shear, and not seeing it at this
time. Still, a few strong storms do look possible at this time and 0-
1 km hangs around 30 kts. Something to monitor for sure.
.LONG TERM...(Saturday through Tuesday)
Issued at 310 PM CDT Wed Apr 10 2019
While high pressure currently promises a dry but rather cool day for
the region Sat, pcpn could already be returning Sunday. Models take
an upper level shortwave trough from the desert southwest, drive in
across TX/southern plains, then lift it through the oh/tn river
valleys Sun/Sun night. Ripples in the northern portion of the upper
level flow could phase with the trough - or not - depending on which
model you buy into. If so, tendency would be to draw the system more
west and place the local area under the deformation region
north/northwest of the sfc low (and thus pcpn chances). EC and GFS a
bit at odds on how this will play out and not a lot of confidence in
either solution. Will ride the blend for now. Temperature profiles
would generally favor rain.
The GFS and EC do agree on some weak shortwave ridging for the start
of the new work week, returning more seasonable temperatures.
However, they also spit a few perturbations out of another trough to
the southwest with also a fairly active northern stream. Pcpn
chances would persist. Looking farther ahead, come Wed night/Thu a
similar looking system to what is expected Sunday could impact the
area - but suffers from the same issues with uncertainties in
shortwave interaction.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 629 PM CDT Wed Apr 10 2019
Late winter storm will bring a range of significant impacts to
aviation through the forecast period including MVFR to IFR
ceilings and MVFR visibility. This evening and overnight, low
level temperatures will hover around freezing, and precipitation
type is expected to vary and include everything from freezing rain
to sleet to snow with rain mixed in at times. Temperatures will
gradually warm tomorrow through the 30s, and by midday
precipitation should change to all rain.
An additional concern is strong surface and low level winds from
the east. Surface wind gusts will exceed 40kts at times. There is
also potential for low level wind shear as wind speeds just above
the surface are forecast to exceed 60 kts.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...Wind Advisory until 1 PM CDT Thursday for WIZ054-061.
Winter Weather Advisory until 1 PM CDT Thursday for WIZ032>034-
041>044-053-055.
Winter Storm Warning until 1 PM CDT Thursday for WIZ017-029.
MN...Winter Weather Advisory until 1 PM CDT Thursday for MNZ079-
086>088-094>096.
IA...Wind Advisory until 1 PM CDT Thursday for IAZ008>011-018-019-029-
030.
&&
$$
SHORT TERM...Rieck
LONG TERM....Rieck
AVIATION...DMD
Area Forecast Discussion
National Weather Service Columbia SC
737 PM EDT Wed Apr 10 2019
.SYNOPSIS...
Dry air will ensure fair weather through Thursday afternoon.
Increasing moisture and a weak surface boundary will provide a
chance of showers and isolated thunderstorms Friday and
Saturday. Additional showers and thunderstorms Sunday and Sunday
night ahead of an approaching cold front. Above normal temps
through Sunday. Cooler and fair early next week.
&&
.NEAR TERM /UNTIL 7 AM THURSDAY MORNING/...
An upper level ridge will build across the region tonight. At the
same time surface high pressure to the north will ridge into the
Carolinas and Georgia. Patchy fog is possible in fog prone
locations early Thursday morning due to mostly clear skies and
light winds. Not expecting ideal radiational cooling since the
center of high pressure will be to our north. Overnight lows
will range from the lower to middle 50s.
&&
.SHORT TERM /7 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
Surface ridge will begin moving off to the east during the day
Thursday. This will allow the warm front that will be situated
off to the south of the cwa to slowly begin moving northward
again. Moisture will be on the increase, but should not be deep
enough to support showers through the day. By Thursday night the
warm front will be moving northward, closer to the cwa, and it
should push through the area during the day Friday. Isolated to
possibly scattered showers may be possible overnight Thursday
night along and north of the warm front due to weak isentropic
lift. Model soundings do not show much instability, so no
thunderstorms expected. By Friday and Friday afternoon the warm
front will be moving north of the area, putting the cwa in the
warm sector. Can not rule out some thunderstorm activity later
in the day Friday since instability does increase slightly with
increase in temperatures and low-level moisture.
Saturday, main upper flow remains out of the southwest. At the
surface, a cold front will be situated off to the west of the
area, and is expected to remain there through the day with
little movement due to the upper flow being parallel to the
front. Model soundings do show an increase in afternoon
instability, with shear values rather weak through the day.
There is some dry air aloft being shown, along with potential
for an inverted-v sounding in low-levels during the afternoon,
so can not rule out a few stronger storms developing during the
peak heating of the day, producing gusty winds. Overall severe
threat appears low though through the day. Mainly isolated
showers Saturday night. Temperatures above normal through the
period.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Sunday will be the day a stronger cold front pushes into and
through the region. The day will start off with the main cold
front still well west of the area, probably somewhere near the
MS/AL border. A prefrontal trough and some convection may also
be in advance of the front at that time. Good southerly flow
through the day ahead of the front will continue to moisten the
atmosphere. Instability on Sunday may not be as high as
Saturday, but the shear across the region will be increasing
through the day as the low-level jet increases ahead of the
front. Can not rule out high shear/low cape event with strong
winds possible. Timing of this system appears to be late in the
day Sunday, lasting into the evening and early overnight hours.
Confidence not high at this time however.
The front pushes east of the cwa by Monday morning, with a few
lingering showers possible across the extreme eastern cwa. Drier
air will push in rapidly however, bringing a return of dry
conditions through the remainder of the period.
Temperatures Sunday remain above normal, then behind the front
only a slight cool down expected, with temperatures generally
around normal.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
High confidence in VFR conditions through this evening.
Possible restrictions in fog and stratus developing late tonight
and continuing into early Thursday mainly at AGS/DNL.
Dry high pressure continues to reside over the area this
evening. Stalled frontal boundary remains well to the south over
southern GA. Some scattered cumulus on a sea breeze is
diminishing with the loss of heating and winds are becoming
light to calm. Main concern overnight is possible stratus/fog
development after 08z through 15z or so. Kept restrictions out
of CAE/CUB due to low confidence and only going with a tempo
group with MVFR cigs/vsbys at OGB due to low confidence there.
Otherwise, winds pick up from the southeast around 10 knots by
16z with mainly scattered cumulus clouds developing and some
higher clouds streaming overhead.
AGS/DNL...Latest several runs of HRRR keep stratus just south
and west of the terminals but NAM and GFS Bufkit soundings and
time heights support stratus development after 08Z continuing
through 15/16Z Thursday. A warm front will be approaching from
the south on Thursday with moisture increasing, although expect
rain free conditions at the terminals through 00Z but cannot
completely rule out an isolated shower late.
EXTENDED AVIATION OUTLOOK...Periods of MVFR or IFR conditions
possible Thursday night through Sunday associated with a frontal
system in the region.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
&&
$$
Area Forecast Discussion
National Weather Service Melbourne FL
1030 PM EDT Wed Apr 10 2019
.DISCUSSION...
Pleasantly mild evening and overnight with light NE flow. Isolated
showers over Martin county will push offshore or diminish by
midnight. Weaker pres grad across the south will allow winds to
become very light to calm. This should allow patchy ground fog to
develop along portions of the Treasure coast. HRRR model is
indicating best chance for fog across north Lake and Volusia but LAV
guidance is not particularly bullish. Will maintain patchy fog for
most of EC FL except along the Volusia/Brevard coasts where onshore
flow should persist.
&&
.AVIATION...Mainly VFR. Patchy ground fog is possible btwn 06Z-12Z
at interior terminals and fog prone FPR. HRRR model is indicating
the best chance for fog between LEE-DAB. On Thu, easterly flow 10
knots.
&&
.MARINE...
No significant changes to current coastal waters forecast.
Tonight-Thu...Sfc/bndry lyr winds have veered to a light to gentle
N/NE breeze and become due East by midday Thu, then E/SE Thu evng.
Seas AOB 2FT nearshore and 2-3FT offshore thru daybreak Thu,
building to 2-3FT nearshore and 3-4FT offshore Thu aftn as the erly
winds push a small swell into the lcl Atlc. Dominant pds 7-8sec from
Indian River Co northward, shortening to arnd 5 sec to the south as
the opposing northerly wind flow/southerly Gulf Stream current
interact with each other. Chc of shras south of Sebastian Inlet
overnight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 64 81 69 85 / 0 10 10 10
MCO 63 88 69 90 / 0 10 10 10
MLB 66 82 71 85 / 10 10 10 10
VRB 65 83 68 85 / 10 10 10 10
LEE 63 87 69 89 / 0 10 10 10
SFB 62 86 69 89 / 0 10 10 10
ORL 63 88 70 89 / 0 10 10 10
FPR 65 84 68 86 / 10 10 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&
$$
Kelly/Rodriguez
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
805 PM EDT Wed Apr 10 2019
.UPDATE...
The latest RAP model showed a mid level trough...with a weak
surface reflection...over FL late this afternoon that slowly
shifts east to the Bahamas by morning. During Thu mid level
ridging slides over the Gulf of Mexico from the west while high
pressure over New England builds down the eastern sea board and
over the Gulf of Mexico.
West and northwest winds continue to diminish and becomes light and
variable over night. This light flow along with adequate low level
moisture from the recent rainfall will support some patchy late night
fog for most inland locations. In addition the decreasing winds have
allowed water levels on the Gulf to subside...reducing the rip
current risk. The beach hazard statement expired at 8 pm. The
forecasts are on track...any changes will be in the near term and
minor.
&&
.AVIATION...
11/00Z TAFs. VFR except for MVFR BR at LAL/PGD 08-14Z. FEW to SCT CU
and SC. NW winds become LTAV...E to SE AFT 14Z. Winds shift to SW to
W AFT 18Z at coastal terminals.
&&
.MARINE...
Benign boating conditions into the weekend as winds slowly veer.
However winds and seas may pick up slightly Sun-Mon.
A weak trough over FL exits to the east tonight as high pressure
begins to build into the Gulf Thu. This high shifts out over the
Atlantic during the weekend as it continues to stretch back across
the Gulf. The high pressure slides east Mon as a cold front moves
into the Gulf.
&&
.Preliminary Point Temps/PoPs...
TPA 68 85 70 86 / 0 0 0 0
FMY 67 87 69 90 / 0 0 0 0
GIF 66 88 69 90 / 0 0 0 0
SRQ 66 83 67 85 / 0 0 0 0
BKV 62 88 64 89 / 0 0 0 0
SPG 70 84 72 86 / 0 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...None.
Gulf waters...None.
&&
$$
UPDATE/AVIATION/MARINE...09/Rude
UPPER AIR...42/Norman
DECISION SUPPORT...69/Close
Area Forecast Discussion
National Weather Service Topeka KS
1103 PM CDT Wed Apr 10 2019
.UPDATE...
Issued at 1057 PM CDT Wed Apr 10 2019
Have cancelled the severe thunderstorm watch for north-central
Kansas as the main wave of convective activity has shifted north
into Nebraska and no redevelopment is being observed or progged by
the CAMS upstream. The surface boundary has slid towards the
Manhattan area with the surface low now lifting northeastward
along this baroclinic zone. This low should pass through the
forecast area in the next 4 to 5 hours with an eastward
progression of the cold front thereafter through the early
morning. The last several runs of the HRRR do develop some light
precipitation along the advancing front in east-central Kansas
towards 08-12Z and have added sprinkle wording to the grids to
account for this scenario.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 345 PM CDT Wed Apr 10 2019
A strong system will continue to impact the area through the short-
term period bringing a chance for severe weather to north-central KS
this evening, and very windy conditions and elevated fire weather
danger tomorrow.
As of 20Z, the center of a 986mb surface low was located near the TX
panhandle and extended up into southwestern KS. A warm front
extended from the low northeastward into north-central KS and south-
central NE. Low level moisture has been advecting northward with the
aid of strong southerly winds, creating a somewhat diffuse
dryline stretching southward through central KS, into western OK
and TX. The area has been capped by an inversion aloft but CAPE
continues to build as surface temperatures warm and lapse rates
steepen in the mid-levels, especially across north-central KS.
Thunderstorms will be possible this evening for the far northwestern
portion of the CWA where the best forcing and dynamics look to align
as the system approaches. Current thinking is that initiation will
occur over parts of north-central KS around 00Z as the surface low
advances into central KS. Storms that develop will have the
potential to reach severe limits with large hail as the main threat.
Damaging wind will also be possible with the strongest storms and a
tornado or two cannot be completely ruled out given decent shear
parameters per sounding and hodograph analysis. Thunderstorms should
move quickly with strong winds in place aloft. The strongest storms
are expected to be out of the area by 04/05Z. The rest of the area
is likely to stay dry with the cap in place.
Thursday will be another very windy day. Thus, a wind advisory will
be in effect from 15Z Thursday to 00Z Friday for the entire CWA.
Westerly winds will gust to near 45 mph at times during the late
morning and early afternoon given the tight pressure gradient
still in place as the strong surface low moves into eastern NE.
Given strong winds and low relative humidities tomorrow, fire
weather will again be a concern.
CAA will also take place Thursday in the wake of a cold front that
looks to move through the CWA in the morning. Temperatures tonight
will fall into the low 40`s in north-central KS to the low 50`s in
east-central KS, and will then struggle to warm during the day.
.LONG TERM...(Thursday night through Wednesday)
Issued at 345 PM CDT Wed Apr 10 2019
The strong mid level upper low will be rotating quickly to the
northeast and into southwest Minnesota by 06Z Saturday.
Precipitation within the deformation zone will just clip the
counties along the Nebraska border during the evening hours Thursday
night. Models have moderated slightly with the cold air behind the
departing system, but most of the area continues to fall to or below
freezing by Friday morning. Temperatures rebound back into the upper
40s to mid 50s during the day on Friday especially across the south
where insolation will be best with few clouds. High pressure will
extend across much of Kansas Friday night and temperatures will
again drop into the upper 20s across north central Kansas and into
the mid 30s across east central Kansas with light winds and clear
skies allowing for good radiational cooling to occur.
The next system to affect the area is a upper low moving across the
southern Plains Saturday then pivoting northeast on Sunday into the
Mid Mississippi Valley. Precipitation is expected to develop within
the deformation zone across much of the area Saturday night. The
heavier precipitation is expected to occur within the TROWAL across
southeast and east central Kansas Saturday night. Thermal profiles
suggest some snow may mix with the rain before ending by
early Sunday morning.
A warming trend occurs early next week as heights rise and WAA
increases ahead of the next trough approaching from the Rockies. By
Tuesday, a northern stream trough will move across the northern
Plains and into the western Ontario by Wednesday morning. A cold
front is forecast to move through eastern Kansas on Tuesday night
and bring another chance of showers along with a slight chance for
Thunderstorms. Temperatures warm back into the 70s on Monday and
Tuesday cooling into the 60s for Wednesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 635 PM CDT Wed Apr 10 2019
Thunderstorms are expected northwest of a line from SLN to MYZ
this evening through 06Z, some of which could produce large hail
and damaging winds. Strong southerly winds lessen this evening,
but LLWS of 45+ kts develops by 01Z and persists through 06-09Z
tonight. Winds then back to the west to northwest for Thursday
with MVFR to possibly IFR stratus moving in towards MHK in the
morning, lifting to VFR levels in the afternoon as it reaches
TOP/FOE.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 10 AM to 7 PM CDT Thursday for KSZ008>012-
020>024-026-034>040-054>056-058-059.
&&
$$
UPDATE...Skow
SHORT TERM...Teefey
LONG TERM...53
AVIATION...Skow