Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 04/19/20
Area Forecast Discussion
National Weather Service La Crosse WI
1040 PM CDT Sat Apr 18 2020
.SHORT TERM...(Tonight through Monday)
Issued at 200 PM CDT Sat Apr 18 2020
Cold front currently dropping in across northern MN will continue to
sink southeast through the afternoon, sliding across and through the
forecast area tonight. The front is associated with an upper level,
currently tracking over southern Canada, eventually swinging through
the northern great lakes overnight/Sun morning. The bulk of the
upper level lift holds there. That said, right entrance region of a
300 mb jet streak could provide a bit more lift this evening as it
drives across the front. Latest RAP paints 100-150 J/kg of SBCAPE on
the front. Saturation isn`t great, but soundings/RH fields have
ample in the 750-600 mb layer. So, the expectation is for scattered
showers and perhaps a few storms to along/ahead of the front, with
higher chances across northern/northeast WI...locally, I-94 corridor
northward. Of note, a more vigorous shower or storm could produce
some enhanced wind gusts as cloud bases look to be around 6-7 kft
with a considerable dry layer sub that (can you say inverted-v?).
Don`t anticipate any severe threat, but gusts into the mid 30s mph
doable. Of course, that dry layer will work against the lighter pcpn
reaching the ground.
Models in good agreement with dropping an upper level shortwave
trough across the Great Lakes Monday night. A leading trough/cool
front precedes the trough, slipping across the forecast area during
the late morning/early afternoon, while another cold front, more
tied to the wave, drops across the region Monday evening. Some weak
instability with the first boundary with good low level lapse rates
(7-9 C/km sfc-850mb). Bufkit soundings point to more stability above
the low layers without much impetus for deeper/stronger convection.
Expect some scattered shower/storms along this first boundary but
with limited potential to be more (at least at this time). Another
shot for showers will come as the cold front drops in for the late
afternoon/evening. Even less instability to work on although low
level lapse rates still good. A few storms remain possible. No tap
to gulf moisture but enough saturation to support rain chances - but
qpf looks on the light side overall.
.LONG TERM...(Tuesday through Saturday)
Issued at 200 PM CDT Sat Apr 18 2020
Kind of a messy upper level pattern for the new week with various
shortwaves spinning across/near the Upper Mississippi River valley.
The GFS and EC in decent agreement at the outset (although some
differences in strength of the various systems), straying more as we
near the weekend.
First off, high pressure should bring sunny but cool conditions for
Tuesday. A shortwave trough then slated to drop southeast across the
northern Great Lakes Wed, dragging a sfc front through the region.
Weak instability along the boundary and could be enough to spark a
few thunderstorms.
Another shortwave takes aim on the region for Friday. Models at odds
with strength (GFS considerably stronger), but both layout some QPF.
Chances would persist through Sat.
As for temps, after the cool day Tue, should see a bump back to more
seasonable readings - with the potential to top 70 Wed (likely the
warmest day of the new week).
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1040 PM CDT Sat Apr 18 2020
VFR conditions expected through the period as surface high
pressure builds in behind a departing cold front. Mid level clouds
will eventually diminish by Sunday morning with skies largely SKC
through the remainder of the period, aside from some patchy
cirrus at times. NW winds will increase a bit after daybreak but
will not be as gusty as today. Some gusts to 20 knots will be
possible through the afternoon before winds diminish towards
sunset.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
SHORT TERM...Rieck
LONG TERM....Rieck
AVIATION...Kurz
Area Forecast Discussion
National Weather Service Bismarck ND
939 PM CDT Sat Apr 18 2020
.UPDATE...
Issued at 929 PM CDT Sat Apr 18 2020
Relatively tight pressure gradient has continued the breezy
northerly winds across the forecast area. We bumped up winds in
the forecast to the max of short-term guidance to account for the
pressure gradient as it sags south over the next several hours.
UPDATE Issued at 629 PM CDT Sat Apr 18 2020
Pressure rises at the surface continues this evening as high
pressure builds in the from the west. Diminishing winds and
clearing skies will be the trend tonight with a quick cool-off in
the surface temperatures. The lows tonight from the inherited
forecast utilized the low-end of guidance which is definitely
reasonable given the high pressure setup tonight. With upstream
surface obs showing dew points in the teens, trends will need to
be watched in case lows have to be dropped further.
Light radar reflectivities continued as well in the northeast and
southwest, with no reported precipitation so far at observing
sites in the forecast area. Lower-end PoPs were kept in for the
next few hours before high pressure eliminates chances for
precipitation.
&&
.SHORT TERM...(This evening through Sunday)
Issued at 130 PM CDT Sat Apr 18 2020
The main forecast issue in the short term period will be fire
weather concerns on Sunday.
Currently, breezy to windy north northwest winds this afternoon. A
couple areas of showers are noted on area radars. The first is
over the northern Red River Valley, and is expected to push
westward during the afternoon, perhaps reaching the far northeast
portion of the CWA before diminishing by early to mid evening. The
second area is located over central into eastern Montana where an
area of weak warm advection lines up with an area of jet energy
and modest lapse rates. This mainly east to west area of showers
will continue to push south and east this afternoon and early
evening, brushing west central and southwest North Dakota.
Elsewhere there may be an isolated sprinkle or shower, but these
are the only two areas we will mention any shower activity this
afternoon or evening.
Cool and quiet tonight as high pressure builds over the forecast
area and will be situated over central North Dakota at 12 UTC. We
utilized a blend of given guidance with colder MOS guidance for
lows tonight. With clearing skies and light winds with a dry
atmosphere, thinking the low side of guidance seems reasonable.
Sunday will be another breezy to windy day. Temperatures will be
similar to a little warmer than today. The main issue for Sunday
will be fire weather concerns in the afternoon as once again we
should be able to mix down those higher winds aloft down to the
surface. This seems similar to Friday afternoon, although at this
time we are not sure how well we mix out and how low the
humidities drop in the afternoon. High temperatures will be about
the same. Winds are also about the same. Comparing GFS MOS
guidance for tomorrow with the guidance for yesterday, afternoon
temperatures and dewpoints are quite similar. Although I believe
we outperformed a bit for winds on Friday, and we ended up with
dewpoints around 10F, compared to the forecast of upper teens. So
for tomorrow if we mix out well and humidities drop into the mid
teens, we will definitely have another near critical fire weather
day. For now we have lowered dewpoints quite a bit from our given
blended guidance (and is generally not quite enough) and we
blended our given guidance with MOS guidance for winds, bumping
them to the higher end of solutions. RAP guidance is suggesting
mid teens for dewpoints Sunday afternoon. We currently have some
mid but mainly upper teens to lower 20s. We will mention near
critical fire weather conditions for Sunday and see how things
play out this evening and overnight. There is another cold front
that drops into northern North Dakota Sunday evening, which may
increase humidities a bit in the late afternoon far north with
increasing cloudiness, but strongest winds will remain north.
Either way, near critical seems reasonable. After coord with SPC
and GGW, SPC will also place an elevated risk of fire weather
conditions across a good portion of western and central North
Dakota.
.LONG TERM...(Sunday night through Saturday)
Issued at 130 PM CDT Sat Apr 18 2020
A northwest flow pattern continues into the extended forecast
period. Overall, we will see milder daytime temperatures with 50s
Monday, then 60s and some 70s Tuesday, then a slow cooldown back
into the upper 50s by Friday. Mostly dry conditions are expected
through Wednesday, but a diurnally driven afternoon/evening
sprinkle or shower can not be ruled out on Monday and again on
Wednesday. Better chances of showers return Thursday through
Saturday, but model agreement is not great as a mean upper level
trough tries to take shape over the central and eastern U.S.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 629 PM CDT Sat Apr 18 2020
VFR conditions expected through the 00Z TAF period. Gusty
north/northwest winds will diminish through this evening and
shift more west to southwest on Sunday.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AE
SHORT TERM...TWH
LONG TERM...TWH
AVIATION...AE
Area Forecast Discussion
National Weather Service Caribou ME
912 PM EDT Sat Apr 18 2020
.SYNOPSIS...
Low pressure will track southeast of the region overnight. A
cold front will cross the region later Sunday night through
early Monday. Low pressure will approach from the west Tuesday
and cross the region Wednesday. High pressure will then build in
for Thursday.
&&
.NEAR TERM /THROUGH SUNDAY/...
9:12 pm update: A tranquil evening as far as the weather goes
across the region. Satellite pictures show a clear sky across
most of the area with just a few patches of mid level clouds in
the Bangor Region and across interior Downeast and the upper
Penobscot Valley. The 00z KCAR sounding was quite dry this
evening. Temperatures as of 9 pm have dropped into the mid 20s
in the colder valleys in the north with 30s common across the
remainder of the region. The temperatures at 9 pm are colder
than forecast in many areas, and have lowered the hourly
temperatures and the lows in most areas. Otherwise, no
significant changes are planned at this time.
Previous discussion:
Low pres will pass well s of the CWA this evening. Satl imagery
showed the best cloud enhancement continuing across the coastal
region, while high pres ridges into the rest of the region from
the ne. Dry airmass in place across the CWA w/very low
dewpoints across the northern and central areas w/readings in
the single numbers and lower teens. Across the interior Downeast
to the coast, dewpoints were in the 20s. Dry airmass will keep
precip at bay and keep most of it off the coast. Could not rule
out some intermittent light rain early this evening across the
outer islands as the low pulls away. Expecting clearing tonight
across the CWA and w/dry air in place, light winds and clearing,
temps will drop off fairly quickly later in the evening. Strong
llvl setting up as noted by the NAM and RAP soundings later
tonight, allowing for colder air at the sfc to be trapped. A
chilly night in store for the region w/overnight lows in the
20s. Given the very low dewpoints across the nne and w, would
not be surprised to see temps by daybreak in the teens in the
aforementioned areas. The NAM and NBM show the potential for
colder temps. The GEM which can pick up on setups similar to
this one looks to be a bit too cold. Used a blend for tonight
and tried to to show the colder temps in the low lying regions.
For Sunday, Clouds will continue to advance eastward during the
day on Sunday ahead of the warm front. S winds will increase
during the day will shift to the SW by late in the day as the
associated cold front apchs from the w. This will allow for WAA
to take hold w/temps shooting well into the 50s. Some areas
across the Maine Central Highlands and the Bangor region could
be reaching near 60 degrees by Sunday afternoon. The NAM is
pointing to some llvl convergence across the w and nw areas for
some light rain showers later in the day. Decided to lean
20-30% pops to play for this potential.
Another item is the SSW winds increasing to 10-15 mph with some
higher gusts and low dewpoints Sunday could lead to increased
fire concerns especially for the Maine Central Highlands into
the Downeast region including Bangor.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
After the mild temperatures on Sunday, an approaching 500mb
shortwave trough will usher in cooler air and help re-establish
below normal temperatures to start the week. A cold front will
cross the region Sunday night, entering the northwestern part of
the CWA around 0z and exiting the coastal waters by around 12z
Monday. The most favorable moisture and lift for precipitation
will be located over northern Maine where vorticity advection is
strongest. Clearing skies are expected Monday as a shortwave
ridge builds in. Despite the clearing, below normal temperatures
aloft as low as around -10C at 850mb across the far north will
favor below normal temperatures at the surface. Increasing
clouds are then expected Monday night ahead of the next storm
system.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
Deterministic guidance and ensembles are in above average
agreement both spatially and temporally regarding the position
of an upper level trough Tuesday into Tuesday night. Its axis is
forecast to stretch from James Bay towards central New England
around 6z Wednesday, taking on a negative tilt. Strong dynamic
lift and intensification of a low level jet will favor a
relatively brief period of moderate precipitation Tuesday
evening. Adjusted temperatures downward several degrees from the
model blend early Tuesday evening to account for evaporational
and dynamic cooling effects. Warm air will likely fail to make
it into northern Maine as the surface low occludes, so
precipitation should only briefly start as rain before switching
over to snow. A minor accumulation of snow is possible across
northern areas, with the most over higher terrain to the west
where surface temperatures and upslope winds will be most
favorable. Elsewhere, rain is expected. At the onset of
precipitation Tuesday evening, strengthening winds aloft along
with forecast profiles moistening from above atop dry low-level
air favors a burst of gusty winds. This is not explicitly shown
in the grids. Also, an isolated lightning strike cant be
ruled out across southern portions of the forecast area.
Lingering convective rain and snow showers will be possible on
Wednesday, before drier conditions take over for Thursday.
Guidance diverges after Thursday, with the European ensemble
mean hinting at another trough moving towards the forecast area
Friday into early Saturday, reinforcing below normal
temperatures and leading to a chance of precipitation.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR right into Sunday for all terminals. Light winds
tonight becoming S on Sunday and increasing to 10-15 kts.
SHORT TERM: Sunday night to Monday: MVFR early at northern
terminals with mainly -SHRA, possibly ending as -SHSN. Becoming
VFR later Sunday night through Monday. SW winds shifting NW with
gusts up to 15 to 20 kts mainly during the morning.
Monday night to Tuesday: VFR. Increasing south winds with gusts
of 20 to 30 kts Tuesday afternoon. Locally higher gusts
possible ahead of precipitation Tuesday evening.
Tuesday night: MVFR with rain south. MVFR to IFR north with
rain changing to snow. SSE winds shifting SW with gusts up to 20
to 25 kts.
Wednesday to Wednesday night: Mainly VFR. Brief MVFR possible
in -SHSN across northern terminals. Breezy with WNW wind gusts
25 to 35 kts.
Thursday: VFR. Not as windy with NW wind gusts up to around 15
kts.
&&
.MARINE...
NEAR TERM: NE winds 10-15 kt will shift to the W overnight and
drop off to 5-10 kt as the low well offshore pulls away. Seas
will drop back to 3 ft. Winds on Sun are expected to shift to
the SSW and increase by the afternoon w/seas building. Llvl jet
of 35 kt will move across the waters and given the fairly good
alignment, will allow some gusty winds closing in around 25 kts
late in the day. This will be mainly for the outer zones. Seas
should respond accordingly to 4-6 ft. Therefore, per collaboration
w/GYX, decided on a SCA from late Sunday into Monday morning.
The SCA may need to be extended.
SHORT TERM: Winds and waves will remain at SCA levels through
Sunday night with SW winds shifting NW late. Winds decrease on
Monday, but seas may take slightly longer to respond, so
extensions of the SCA for waves are possible Monday. A brief
break with conditions below SCA can be expected Monday afternoon
into Tuesday morning, before winds and seas ramp up to SCA
again Tuesday afternoon and evening through approximately
Thursday morning with the next storm system. There is also a
chance for gusts to gale force Tuesday night into Wednesday.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory from 5 PM Sunday to 8 AM EDT Monday for
ANZ050-051.
&&
$$
Near Term...CB/Hewitt
Short Term...MStrauser
Long Term...MStrauser
Aviation...CB/Hewitt/MStrauser
Marine...CB/Hewitt/MStrauser
Area Forecast Discussion
National Weather Service Cheyenne WY
530 PM MDT Sat Apr 18 2020
.SHORT TERM...(This evening through Sunday)
Issued at 240 PM MDT Sat Apr 18 2020
GOES-16 Water Vapor Imagery shows a deep trough moving into the
southwestern CONUS with a leading shortwave propagating east of
the Four Corners region. This shortwave has brought showers to
much of CO and high clouds over southern portions of the CWA.
Chances for precipitation are fairly low through the afternoon,
but a stray rain shower may be possible along/near the CO/WY
border. Looking farther west, another shortwave along the UT/ID
border approaches the CWA which could support light snow showers
on the higher peaks of the Sierra Madre Range. However, recent
RAP analysis shows a weaker shortwave than previous forecasts so
precipitation may be limited through this evening.
A cold front will begin to push south through the CWA east of the
Laramie Range this evening. The front is expected to backup along
the eastern slopes of the Laramie Range where patchy fog is
possible after midnight behind the front, especially near Chadron
and Alliance with increasing low-level moisture. Additionally,
light snow showers may develop early Sunday morning behind the
front over northern Niobrara County in Wyoming and the northern
Nebraska Panhandle, but little to no accumulation is expected at
this time. Heaviest precipitation should remain north of the CWA.
Heading into Sunday afternoon, breezy conditions can be expected
for southeast Wyoming with gusts up to 40 MPH, especially near the
wind prone areas. Scattered rain showers will develop with
passing impulses and limited, but non-zero, instability. Chances
for precipitation should diminish by 9 PM MDT.
.LONG TERM...(Sunday night through Saturday)
Issued at 226 AM MDT Sat Apr 18 2020
A gradual warming trend should persist into the extended period
w/ general upper-level ridging in place. The outlook will become
more muddled mid/late week as the GFS/ECM are in very good
agreement w/ deep troughing becoming established across the
western and central CONUS. As such, expect a transition to a
cooler and more unsettled pattern from Wednesday onward.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 526 PM MDT Sat Apr 18 2020
Wyoming TAFS...VFR, except for MVFR at Cheyenne from 10Z to 15Z.
Wind gusts to 22 knots at Rawlins until 01Z, then to 30 knots at
all terminals after 15Z Sunday.
Nebraska TAFS...VFR at Chadron, Alliance and Scottsbluff until
09Z, then MVFR until 15Z, then VFR. Wind gusts to 24 knots at
Scottsbluff after 19Z Sunday.
VFR at Sidney until 12Z, then IFR until 15Z, then VFR. Wind gusts
to 18 knots until 04Z, then to 23 knots after 19Z Sunday.
&&
.FIRE WEATHER...
Issued at 226 AM MDT Sat Apr 18 2020
No fire weather concerns. Despite periods of breezy conditions
and a few chances for an isolated thunderstorm, humidity values
should remain well outside of critical thresholds.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...MB
LONG TERM...CLH
AVIATION...RUBIN
FIRE WEATHER...CLH
Area Forecast Discussion
National Weather Service Houston/Galveston TX
1027 PM CDT Sat Apr 18 2020
.UPDATE...
Things have quieted down after a handful of storms produced hail
ranging in size from pea-size to nearly 2 inches in a couple
locations. In its wake, we`re seeing a mish-mash of fog, low
clouds, and drizzle that should dominate a good portion of the
night. Another upper disturbance will approach the area in the
morning, and things start to get tricky again...
In general, the environment looks favorable for severe storms
again from Sunday morning into the mid-to-late afternoon. The HRRR
and HREF both suggest sufficient instability for strong to severe
thunderstorms - 1000 J/Kg seems a relatively easy reach, but also
potential to push right through 2000 J/Kg as high as 3,000 J/Kg
on the high end, though I`m unsure just how realistic that may be
given the clouds in place. Even if the clouds hold things back
some, instability is not likely a limiting factor there. There is
a cap in place, but HRRR soundings seem to erode that just enough
at College Station by 14Z, and at Houston by 16Z. Once the cap is
weak enough (or gone), storms should be a fairly straightforward
proposition along a cold front swinging through the area. Any
storms will also be able to tap into strong lapse rates above the
cap.
In addition to sufficient instability, deep layer shear looks more
than enough to sustain organized updrafts, as long as it is not so
strong that it overpowers the balance with any future storms`
cold pools. There is a fair amount of turning in the lower
atmosphere which gives me a mild concern about tornado threat, but
wind speeds are not progged to be terribly impressive in the lower
part of the boundary layer in our area which results in a fairly
ugly looking hodograph. Some HRRR soundings give flashes of more
impressive low level wind profiles, but they tend to be
convectively tainted, so I`m generally discounting that idea.
Tornadoes probably can`t be completely ruled out here in the land
of the super shower, but damaging winds and ESPECIALLY hail seem
the more likely threats. Hail to, or exceeding, 2 inches is
possible again.
So...we`ve got ourselves an atmosphere that should support severe
weather over Southeast Texas tomorrow morning and afternoon. What
do the models do with that? Well, for the most part, it`s not
terribly impressive. Despite a cap that is nearly, or entirely,
gone - most of the CAMs focus convection north of a line from,
say, College Station to Huntsville. I wonder if forecast soundings
may simply be showing too much erosion of the cap, and that may
not be a terrible idea if low clouds hold the capping inversion in
place too long into the morning. Indeed, if it weren`t for today`s
earlier performance, the broader environment, and the fact that
the WRF-ARW drives its strongest storm right into the heart of
Houston, I would feel more comfortable using that CLL-UTS line as
the border of where the best potential is. But, as long as there`s
a supportive environment and still some model support, it`s
probably more responsible to set a line roughly along I-10
northward, though there remains a LOT of uncertainty for the
Houston metro. You know...just like the last event...or two...or
three (or more?).
For what its worth, using the HREF updraft helicity probabilities
as a proxy for the strongest storms, the best signal for severe
weather is well north of Houston, from College Station to
Huntsville northward, and pushing east into the Deep South later
in the day and into the night. It`s probably best to focus there.
But we need to stay aware that there is a potentially good
environment and limited model support all the way south down to
I-10. It will be conditional on the cap eroding enough and
getting sufficient lift to take advantage, but there`s fuel there
should we meet that condition. Just because the best odds are
well north of Houston, doesn`t mean there are ZERO odds in
Houston. Coastward of that, the severe threat gets much more
tenuous.
&&
.PREV DISCUSSION /Issued 632 PM CDT Sat Apr 18 2020/...
.SHORT TERM [Tonight through Sunday]...
An inland advancing warm front will provide enough lift to produce
interior scattered showers and thunderstorms. Much of this activity
will be elevated above the frontal surface so the main threats from
more organized, strongest cells will be localized downburst wind
gusts and hail. The warm front washes out this evening and any
lingering northern county convection will weaken while periods of
more southern county light precipitation (primarily drizzle or a
light shower) hangs on through sunrise. Low overcast and patchy fog
is also possible within this moistened air mass (1.5 to 1.6 inch
pwats). Under this warm air advection regime, morning temperatures
will only fall into the middle to upper 60s up north to lower 70s
near the immediate coast.
A somewhat shallow shortwave trough pulling out of the Southern
Plains tomorrow will create enough upper level divergence, in tandem
with an approaching cold front, to prime the area for another round
of late tomorrow morning into the early afternoon convection.
Thermodynamics are pretty impressive during mid to late Sunday
morning with northern CWA greater than 3k J/Kg**2 CAPE, neg -7 to -9
L.I.s`, 25-35kt low level bulk shear and near 40 K indices
indicating more strong thunderstorm coverage. An anticipated
strengthened low level jet out of the southwest also fortifies the
active Sunday weather argument. Super high pwats in the 1.8 inch
range just downstream of the best frontogenesis does suggest that
there is a minor high rainfall-leading-to-nuisance-flooding threat.
As the surface low passes across northeastern Texas late tomorrow
afternoon, moderate southwesterly to westerly winds will assist in
pushing thermometers up to the lower to middle 80s. 31
.LONG TERM [Sunday night through Saturday]...
Fairly unsettled pattern will remain in place this week. Surface
high pressure and associated benign weather will become
established early in the week which will give way to more onshore
flow ahead of next fast moving system Tuesday and Wednesday. There
is a bit more agreement with the mid week system amongst the
guidance, although still some variances in timing of the fast
moving trough. Regardless, this will bring another round of active
weather increasing rain chances- including the potential for some
strong to severe thunderstorms Wednesday. In the wake of this
system, expect drier weather to close out the week into the
weekend under fairly zonal flow regime. All in all, expect temps
will be rather warm for April with highs well in the 80s each day,
with temps approaching 90 possible next Saturday.
Evans
MARINE...
Easterly surface winds will turn more towards an onshore south-
southeast wind and steadily increase tonight. Should see winds
strengthen out of the southwest in the wake of a weather system
tomorrow afternoon into the 15-20 mph range which may require a
SCEC in later forecasts. Winds will slacken considerably early
next week with light northeast winds Monday. A SCEC may be
required Wed/Wed Night as winds again increase in advance of
another cold front midweek.
Evans
.AVIATION [00Z TAF Issuance]...
Isolated strong to severe storms are making their way out of the
area to the east, with drizzle, a few showers, and even a couple
lingering thunderstorms left behind this evening. Eventually, low
ceilings, fog, and drizzle will prevail, giving IFR conditions at
most, if not all sites. May see a bit of improvement in the
morning, but will be accompanied by another round of thunderstorms
on a cold front sweeping in. Beyond the scope of this TAF cycle,
better flight conditions should come in once post-frontal air
takes over. But until then, it`ll be MVFR at best.
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 66 85 57 81 60 / 40 60 0 0 0
Houston (IAH) 69 83 61 84 62 / 90 60 0 0 0
Galveston (GLS) 71 77 67 78 69 / 20 30 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
UPDATE...Luchs/47
SHORT TERM...31
LONG TERM...Evans
AVIATION...Luchs
MARINE...Evans
Area Forecast Discussion
National Weather Service Wichita KS
640 PM CDT Sat Apr 18 2020
.SHORT TERM...(This evening through Tuesday night)
Issued at 352 PM CDT Sat Apr 18 2020
Gusty winds today were the result of a surface low developing over
southeast Colorado. This low will move south and east across
Oklahoma tonight through tomorrow as shortwave embedded in the
midlevel flow moves across the region. The shortwave is currently
over the dessert southwest as seen by water vapor imagery. This
shortwave will combine with increased warm moist advection across
CWA and support scattered showers and storms across the area tonight
through early tomorrow morning.
The better instability overnight will remain near and south of the
OK/KS border. Do not expect severe storms tonight, but a rowdy
storm or two with small hail and gusty winds can`t be ruled out
across the southern tier of the CWA. Thinking the best coverage
will be across south central and southeast KS where the best
moisture/lift will be. However, CAMS models hint of increased
chances across central KS, along the deformation zone. Confidence
in central KS coverage is low given lack of appreciable moisture.
A few showers may persist into early afternoon tomorrow across
southeast KS where the most recent RAP runs keep the warm moist
advection around. Otherwise, tomorrow should shape up to be a rather
pleasant day with highs in the mid 60s with skies gradually
clearing throughout the day. Overnight into Sunday central KS
might see some light showers with weak moisture advection and lift
overhead.
Otherwise quiet weather conditions and a nice warming trend
expected until mid week when an upper low arrives from the
southwest. Expect temps to rise into the mid 70s by Tuesday.
.LONG TERM...(Wednesday through Saturday)
Issued at 352 PM CDT Sat Apr 18 2020
An upper low will scoot across the southwest CONUS very late
Tuesday. Models show some agreement on an early Wednesday arrival
for the Central Plains, and moving overhead or south of the area
by late Wednesday night. There remain some timing issues, but the
consensus is the upper low and sfc low centers remain south of
area. Showers and storms can be expected Wednesday. However, as
the previously forecaster mentioned, there doesn`t appear to be
any indication of robust daytime convection with the best
instability showing up much further south across Oklahoma and
Texas. Elevated storms will be our best chance. Models continue to
deviate on when precip will pull away from the area.
A couple of weak ripples in the flow will keep the extended rather
unsettled, but chances of severe weather continue to be quite low.
Expect seasonable temperatures through the extended.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 634 PM CDT Sat Apr 18 2020
A upper level wave will move eastward across Kansas later tonight.
Elevated showers/storms over western Kansas will spread east into
central and southern Kansas overnight. Meanwhile low clouds in the
MVFR range look to develop across southern Kansas late tonight.
Winds will diminish then switch around to a light north then
northeast direction by Sunday morning.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 46 67 43 71 / 30 20 10 10
Hutchinson 44 67 42 71 / 30 10 10 10
Newton 44 65 42 70 / 20 10 10 0
ElDorado 45 66 42 71 / 20 20 10 0
Winfield-KWLD 47 66 44 72 / 50 20 0 0
Russell 43 67 41 72 / 30 20 20 10
Great Bend 44 67 41 71 / 40 10 10 10
Salina 44 67 42 71 / 20 20 20 10
McPherson 44 67 41 71 / 20 10 10 10
Coffeyville 47 65 42 71 / 50 50 0 0
Chanute 46 65 41 71 / 40 40 10 20
Iola 46 65 40 71 / 40 40 10 20
Parsons-KPPF 46 65 42 71 / 50 40 0 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...KMB
LONG TERM...KMB
AVIATION...CDJ
...Updated Aviation Forecast Discussion...
.DISCUSSION...
Issued at 238 PM CDT Sat Apr 18 2020
Despite the windy conditions with gusts up to 35 mph today,
abundant sunshine and temperatures in the mid 60s to lower 70s
feels pretty good! There is a cold front that has moved into
southern SD, and that will move through the region overnight.
Moisture is very limited, and while the HRRR model suggests that
some sprinkles could occur, feel it`s probably overdone. Meanwhile,
there is a weak upper level wave moving out of eastern CO. This
could generate scattered showers/storms across portions of KS
overnight, and in similar fashion, the HRRR generates spotty
showers in southeast NE, but other models keep precip south of
the forecast area. Thus a dry forecast overnight, with just a wind
shift, and perhaps scattered clouds.
Sunday will be cooler than today with a northerly wind. Highs in
the mid 60s to lower 60s, but generally dry. Although, the next
clipper moving out of the northern Rockies will be approaching,
and could generate isolated showers in extreme northeast NE toward
the end of the afternoon, but moreso Sunday night as the wave
moves through the region. Temperatures remain warm enough for just
a mention of rain with lows from 37 to 40.
Monday could see lingering showers south of I80 in the morning,
but those quickly depart, with a west-northwest wind setting up.
This is generally a warming wind for us, and temperatures climb
back into the mid to upper 60s. Tuesday brings a shift to southeast
to easterly winds with highs again in the 60s and 70s.
Wednesday will be the next chance of rain as the next trough
moves out of the Rockies. The bulk of the energy remains south of
the forecast area, but at the same time, a weak front tries to
push into the region from the north, although doubtful the front
will be able to push through given overall weak forcing aloft
across the Midwest. Will still have precip chances mostly south of
I80 with warm temps in the 70s. Thursday looks dry with highs in
the mid 70s. But precip chances increase again by Friday and
Saturday as a couple of waves move through the area, although
confidence of exact timing is low at this time.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday evening) Issued
at 942 PM CDT Sat Apr 18 2020
High level clouds continue to linger through the area as a weak
cold front continues to make its way through the forecast area.
Behind the front, northerly winds are expected around 5 to 10 kts
and will last through much of Sunday. Sunday evening, winds will
become more easterly around 5 kts, with increasing high clouds.
Sunday night, there will be a chance for rain showers, with MVFR
conditions possible at KOFK. Otherwise, VFR conditions will
prevail.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...None.
IA...None.
&&
$$
DISCUSSION...DeWald
AVIATION...Gunkel