Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/17/20
Area Forecast Discussion
National Weather Service Cheyenne WY
812 PM MDT Mon Mar 16 2020
.UPDATE...
Issued at 800 PM MDT Mon Mar 16 2020
There is potential for areas of light freezing drizzle through the
remainder of the evening & into the overnight, mainly along the I-
80 corridor between the Summit and Sidney. Model soundings suggest
deep saturation between 0 and -10 deg C after 10 PM, helping limit
potential for ice crystal growth and promoting -FZDZ. Do not think
we will see significant ice accretion, but some areas may see one-
or two hundredths of an inch of ice, leading to a slick AM commute
across these areas. Updates have been sent.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 315 PM MDT Mon Mar 16 2020
Low clouds associated with a semi-stationary frontal boundary are
still lingering from extreme eastern portions of Laramie County near
Pine Bluffs to the northwest up to Casper this afternoon. The low
clouds will slowly retreat to the east and northeast, later this
afternoon and evening. This will keep temperatures in the western
and northern portions of the Nebraska Panhandle cool, with
temperatures struggling to reach 40 degrees in several areas.
Short term model guidance from the HRRR and NAM showing a few stray
rain showers are possible this evening, but not expecting much.
Clouds are anticipated to build east to west late this evening
thanks to the frontal boundary advancing toward Rawlins overnight.
This will assist with temperatures staying elevated across the
region overnight in the 20s most likely. Clearing is not expected
across the region until afternoon as the semi-stationary frontal
boundary retreats out of the area by Tuesday evening.
Temperatures will still rebound nicely tomorrow with above average
readings across the region, despite clouds early on. Mostly cloudy
conditions across the area will give way to afternoon sunshine from
west to east. Areas just to the east of the Laramie Range will see
temperatures in the low to mid 50s, with some cities close to 60
degrees.
.LONG TERM...(Tuesday night through Monday)
Issued at 315 PM MDT Mon Mar 16 2020
...Major Winter Storm to Impact the Area Wednesday Night Through
Friday Morning...
Low currently off the California coast tracks down near the
California Baja Tuesday evening and then tracks inland into
northern Arizona Wednesday evening. Upper ridge axis passes east
into northeastern Wyoming and western South Dakota Wednesday
evening with broad upper level diffluence on the western side of
the ridge Wednesday evening. Near the surface...low undergoes
cyclogenesis over northeastern Colorado. 110-120kt jet in
favorable position for additional lift across our southeastern
CWA. We will have a frontal boundary in place across the east
slopes of the Laramie Range.
GFS and ECMWF both showing widespread heavy snowfall developing
Wednesday night and becoming widespread Thursday. GFS showing
winds increasing Thursday morning...up to 45-50kts at 800mb and
40-45kts at 700mb along and east of the Laramie Range. We approach
55-60kts at 750 and 800mbs across the Panhandle late Thursday
morning...so blizzard conditions looking likely. Due to the
widespread nature of this snow and the strong winds...decided to
issue a Winter STorm Watch for almost the entire CWA.
First low tracks east Friday morning...but ECMWF showing a
secondary shortwave tracking across central Colorado Friday
afternoon and evening. Snow may continue Friday evening for a
time...especially the Snowy and Sierra Madre Ranges as well as
the I-80 Corridor along southern Wyoming.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday afternoon)
Issued at 515 PM MDT Mon Mar 16 2020
VFR expected to prevail at KRWL and KLAR through the period. KCYS
will be VFR early this evening but then cigs lower to IFR as a low
stratus deck just to the northeast moves back over the terminal.
Widespread MVFR/IFR cigs across the Neb Panhandle terminals through
Tuesday with some patchy fog as well, though some improvement
possible Tuesday afternoon.
&&
.FIRE WEATHER...
Issued at 315 PM MDT Mon Mar 16 2020
Minimal fire weather concerns over the next week as southeast
Wyoming and Nebraska Panhandle will have a weak frontal boundary
that meanders from the east slopes of the Laramie Range out into
the Panhandle. East of the front...low clouds and high humidity
will prevail. West of the front...sunny skies and dry conditions
expected...though afternoon humidity will stay well above critical
levels. A strong low pressure system begins to move into northern
Colorado Wednesday afternoon and will slowly track into northeast
Colorado Thursday. This low will bring widespread heavy snow and
near blizzard conditions to most areas...especially Thursday
morning through Friday morning.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Winter Storm Watch from Wednesday evening through late Thursday
night for WYZ103>106-109-110-115-116.
Winter Storm Watch from Wednesday evening through late Thursday
night for WYZ101-102-107-108-117>119.
Winter Storm Watch from Wednesday afternoon through late
Thursday night for WYZ112-114.
NE...Winter Storm Watch from late Wednesday night through late
Thursday night for NEZ002-003-019>021-054-055-095-096.
&&
$$
UPDATE...CLH
SHORT TERM...BW
LONG TERM...GCC
AVIATION...RE
FIRE WEATHER...GCC
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
636 PM CDT Mon Mar 16 2020
.AVIATION...
Little to no change to the aviation forecast with a return of IFR
ceilings expected tonight. Looks like most of the rain/storm activity
will be just beyond the period. Left in vicinity showers for
tomorrow afternoon for AUS given the slightly higher POPs for our
northern areas. Ceilings should lift to MVFR then low-end VFR by the
afternoon hours tomorrow. Persistent SE winds for the entire period.
&&
.PREV DISCUSSION... /ISSUED 236 PM CDT Mon Mar 16 2020/
SHORT TERM (Tonight through Tuesday Night)...
A mostly cloudy and mostly dry night is forecast for tonight. The
HRRR sparks off a few isolated showers, and maybe a thunderstorm to
the south of San Antonio this evening. We have seen isolated showers
in these areas, and areas east of I-35 thanks to the remnants of
last nights MCS so a slight chance of rain has been kept in the
forecast for the early overnight hours to account for the HRRR`s
forecast outcome. A weak shortwave will track across northern Mexico
tonight and cross into the Rio Grande Plains late tonight and early
Tuesday morning. Both global and high resolution models show
significantly less shower and thunderstorm activity associated with
this shortwave compared to yesterday`s and what is forecast for late
tomorrow and Wednesday. The greatest chance for any scattered
activity will be along the Rio Grande Plains overnight.
Tuesday will be warm and between shortwaves in the upper level
southwesterly flow. This will result in another cloudy and warm day.
While organized precipitation is not expected a stray shower or
storm can`t be ruled out due to the moist environment.
The main show begins Tuesday night across the Rio Grande Plains.
While the main upper low will still be well to our west across
Southern California, a shortwave will traverse Texas Tuesday night
into Wednesday. This shortwave will be enough to kick off another
MCS feature similar to what was seen this morning across the Rio
Grande. This complex of showers and storms will pack a one-two punch
as isolated pockets of heavy rainfall could produce some minor
flooding, while strong to severe storms will also be possible.
Overnight rains from this morning produced a decent swath of 1-3
inches of rain in Val Verde and Edwards Counties. These areas are
not in drought and with addition rounds of rain forecast for Tuesday
night through the end of the week some minor flooding will be
possible. Forecast soundings for Tuesday night show ample shear (50+
knots), decent CAPE (1500 j/kg), and good moisture (1.4 inch
precipitable water values). This could come together with the lift
from the shortwave to produce a few stronger storms with damaging
thunderstorm winds being the main threat. SPC has focused the severe
risk Tuesday night for Val Verde and Edwards Counties as the storm
complex should weaken overnight as it moves east into the Hill
Country.
LONG TERM (Wednesday through Monday)...
The system from Tuesday night should mostly be decayed by Wednesday
morning with just a slight chance of showers and storms remaining for
the northern two-thirds of the area during the day. Highs will top
out in the 70s and 80s.
The upper patten will remain persistent with a trough axis to our
west. This should allow for another round of storms to develop to our
west Wednesday afternoon and move east into the CWA in the evening
and overnight hours. There are some indications that this activity
will not be as much of a rain producer, but chances are better that
the system holds together farther east with higher PoPs finally
making it for areas along and west of the I35 corridor. The latest
SPC Day 3 Outlook shows this well with the marginal risk extending to
just west of the I35 corridor. Hail and gusty winds would likely be
the main threats for any low-end severe weather for us.
On Thursday, slightly drier air filters into the area behind the
Wednesday night system which will shift the better PoPs to the
northeastern CWA. However, a cold front will arrive Thursday night
which should bring a chance of widespread showers and storms to most
of the area Thursday night and Friday. In addition, much cooler
weather can be expected with highs Friday and Saturday in the 50s and
60s. A weak impulse will allow for some overrunning conditions to
commence on Saturday with continued high PoPs for most areas Saturday
into Sunday. Slightly drier weather is expected for Monday with
temperatures back into the 60s and 70s.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 66 80 67 80 68 / - 30 20 20 40
Austin Bergstrom Intl Airport 65 81 66 81 67 / - 30 20 20 40
New Braunfels Muni Airport 66 81 66 81 66 / 20 20 20 20 40
Burnet Muni Airport 64 77 65 77 65 / - 30 40 30 60
Del Rio Intl Airport 67 82 66 82 64 / 30 20 60 20 70
Georgetown Muni Airport 65 79 66 80 66 / - 30 30 30 50
Hondo Muni Airport 66 82 65 83 65 / 20 10 40 20 60
San Marcos Muni Airport 66 81 66 81 66 / 20 20 20 20 40
La Grange - Fayette Regional 67 81 68 83 69 / - 30 10 20 20
San Antonio Intl Airport 67 81 67 81 67 / 20 20 30 20 50
Stinson Muni Airport 67 82 67 83 68 / 20 20 20 20 40
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Short-Term/Aviation...EWilliams
Long-Term...YB
Decision Support...BMW
Area Forecast Discussion
National Weather Service Wichita KS
621 PM CDT Mon Mar 16 2020
.SHORT TERM...(This evening through Thursday night)
Issued at 357 PM CDT Mon Mar 16 2020
A deep midlevel system currently spinning off the coast of
California is progged to continue to dig south along the coast
through Wednesday. The system will eject a lead wave which will move
across the region late tomorrow. In the meantime, transient lift and
moisture will provide chances of drizzle and rain this evening and
overnight.
Widespread precipitation is expected tomorrow night as the lead
wave moves overhead amidst anomalous moisture of 1 to 2 standard
deviations above normal. Southern KS continues to be the focus for
the heaviest rainfall where the concern for flooding will be
greatest given already moist soils. A widespread 0.75 to 1.0 inch
of rain is possible across south central and southeast KS
overnight tomorrow. In addition, there is a chance of strong to
severe storms tomorrow night.
The RAP and NAM suggest 1,000-1,500 J/kg of 850-300 MUCAPE with 30-
40 kts of 1-6 km bulk shear. At this time it appears storms will
remain elevated resulting in the main threats of strong wind
gusts and nickel to quarter sized hail. Expecting showers and
storms to shut off by Wednesday afternoon across much of the area,
as they exits from west to east.
Only a small break in precipitation is expected late afternoon
Wednesday before chances of precipitation increases again
overnight Wednesday into Thursday as the main upper low traverses
out from Arizona northeastward into Colorado. Widespread rainfall
expected again with ample lift spreading across the area. Heavy
rainfall, flooding potential, and the potential for strong and
severe storms will again be the story through the overnight.
Strong moisture transport will continue to advect in over the area
resulting in continued anomalous precipitable water anomalies.
Southern KS, especially southeast KS, will again be the focus for
the heavier precipitation. An enhanced flooding threat will be a
concern particularly along and east of I-35 on Thursday, after
continued rainfall across these area. Portions of southeast KS may
pick up another inch of rain. Of interest, the potential for
severe storms is increasing for the overnight period Wednesday
into Thursday. Soundings suggest sfc based storms could be
possible. However, will wait for later model runs to resolve the
details.
Models have come in agreement to place the mid level low and sfc low
vertically stacked in northwest KS/northeast CO by 18z Thursday.
Thus, chances of severe storms Thursday afternoon continues to
drop, as now the EC/GFS/NAM all paint the mid level dry slot
across the entire CWA by 18z. However should the storm system slow
down, the threat of severe storms Thursday afternoon would need
to be revisited. Winds continue to be trended up to reflect the
high confidence in strong winds as the system pulls through.
.LONG TERM...(Friday through Monday)
Issued at 357 PM CDT Mon Mar 16 2020
Much quieter conditions expected in the long term. However much
colder conditions can be expected too, with lows Friday night
expected to dip into the teens and 20s area wide and high temps
for the weekend looking well below normal. Low chances of snow and
rain come back into the forecast Sunday and Monday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 619 PM CDT Mon Mar 16 2020
Low clouds will continue blanket the region for the next 24hrs
with IFR cigs persisting through the night. Cigs look to rise into
the MVFR category during the day on Tuesday with winds switching
to east and southeast.
&&
.FIRE WEATHER...
Issued at 357 PM CDT Mon Mar 16 2020
Very high fire danger across the area Thursday and Friday.
However, for areas that receive the forecast heavy rainfall across
southern KS, the fire weather concern will be minimal.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 42 53 51 75 / 30 30 100 30
Hutchinson 40 50 48 74 / 20 30 90 20
Newton 40 51 49 74 / 20 20 100 30
ElDorado 41 53 50 75 / 30 20 100 40
Winfield-KWLD 44 55 53 77 / 30 40 100 40
Russell 36 45 42 72 / 20 50 80 10
Great Bend 37 46 44 74 / 20 50 80 10
Salina 38 50 47 73 / 20 20 90 20
McPherson 38 50 47 72 / 20 30 90 20
Coffeyville 45 59 54 75 / 50 30 100 70
Chanute 43 56 53 74 / 30 20 100 70
Iola 42 55 52 74 / 30 10 100 70
Parsons-KPPF 44 58 54 75 / 40 30 100 60
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...KMB
LONG TERM...KMB
AVIATION...CDJ
FIRE WEATHER...KMB
Area Forecast Discussion
National Weather Service Paducah KY
804 PM CDT Mon Mar 16 2020
.UPDATE...
Issued at 804 PM CDT Mon Mar 16 2020
Lightning has made it as far east as Carter/Ripley counties in
SEMO. RAP forecasts show elevated instability continuing east
overnight. We added thunder over the southern 2/3 of the area as a
result for the rest of tonight.
UPDATE Issued at 644 PM CDT Mon Mar 16 2020
Updated Aviation Discussion for 00z TAFs.
&&
.SHORT TERM...(Tonight through Tomorrow)
Issued at 248 PM CDT Mon Mar 16 2020
A weak disturbance has brought light showers to most of the
region this afternoon. High pressure is keeping winds light and
limiting forcing for this system. An additional weak system is
located in southwestern Arkansas and will move into the region
tonight with additional light showers, primarily for SE Missouri
and W Kentucky. Rainfall totals now through the night will
generally be light, up to a quarter inch, with the highest
amounts to the south. Higher humidity and cloudy skies will keep
highs near 40 overnight.
The second system will move out of the area by mid-morning
bringing dry weather for the rest of Tuesday. High pressure will
move across the Upper Midwest, resulting in shifting winds
towards easterly. Skies will remain mostly cloudy through the day
with more sun peeking through in the Evansville Tri-State. Highs
will be in the mid to upper 50s, near average for mid-March.
.LONG TERM...(Tomorrow night through Monday)
Issued at 248 PM CDT Mon Mar 16 2020
For Tuesday Night through Wednesday Night...
The WFO PAH forecast area will be in a transition period, as the low
level warm advection zone (and surface warm front) progress from
south to north across the area. The NBM (National Blend of Models)
has continued to broadbrush higher chances of rain across eastern
sections of the WFO PAH forecast area Tuesday Night into early
Wednesday morning, outside of the main forcing in main warm conveyor
belt/channeled vorticity zone further to the west (in western and
central Missouri). Continue to utilize the blend of the GFS/Canadian
guidance to postpone the eastward translation of near categorical
PoPs from Tuesday night into mid-morning on Wednesday, especially
over southeast MO and southern IL. Even WPC has reduced QPF until
the last 6 hours (1 am-7am Wednesday) of Tuesday night, and only
light QPF (less than 0.10 inches). The ensemble and deterministic
model runs the last 3-4 days have been focusing the higher QPF (rain
amounts) along the main warm conveyor belt inside the warm sector of
the low pressure system (low centered in the front range of the
Central Rockies (eastern CO/western KS). This has focused the
primary efficient rain processes over southeast Missouri during the
early morning hours (after 7 am CST), translating the heavier
rainfall amounts over southern Illinois and southwest Indiana
between 10 am and 4 pm Wednesday, then translating the heavy rain
east of the area after 00z. Leaned closer to the better initialized
GFS family of model solutions versus the Canadian, which keeps a
progressive swath of higher QPF moving across the entire WFO PAH
forecast area throughout the day. From late Wednesday night into
early Thursday AM (1am-7am Thursday), should see the main focus of
precipitation drop into southern sections of the WFO PAH forecast
area (southern part of southeast MO/western KY) in a weak
convergence zone south of the pre-existing convection earlier in
the day on Wednesday. Again, there are marked differences between
the GFS and Canadian solutions and will need to be monitored as we
move closer into the domain of higher resolution Convection Allowing
Models (CAMs).
For Thursday into Friday morning...
The GFS/Canadian are finally coming into consensus with the next
wave of convection moving into the WFO PAH forecast area. The GFS
has been focusing on pre-frontal convective activity during the
afternoon and evening hours, eventually transitioning into a broader
heavier rain event during the evening hours as the main upper low
moves north of Lake Superior and shears out with time late Thursday
night and Friday morning. Anticipate the greatest time of concern
for strong to potential severe storms will be along and ahead of the
pre-frontal trough, when there will be modest surface to 1 kilometer
shear of 35-50 knots (about 2/3rds of the surface to 6km shear), 100-
200 helicity, and decent lapse rates in the vicinity of the frontal
boundary. The question, as SPC posed in the day 4 outlook , will be
when the flow aloft becomes more parallel (versus across the frontal
boundary/orthogonal flow), as well as any pre-existing convection.
This would likely be during the afternoon and evening on Thursday.
For Friday afternoon through Early Monday...
Dry weather should dominate has high pressure builds across the
region. Another in a series of low pressure systems is forecast to
move into the desert southwest Sunday night, which would place
western sections of the WFO PAH forecast area in southwest flow
again, with a small chance of rain returning by Monday morning to
the area.
&&
.AVIATION...
Issued at 644 PM CDT Mon Mar 16 2020
Ceilings will gradually deteriorate through the evening and
overnight hours, progressing from MVFR to IFR in most locations.
Light rain and drizzle may lead to some MVFR to possibly IFR vsby
restrictions at times as well this evening and overnight.
Improvement is expected to occur during the day on Tuesday,
although cigs at southern terminals (KCGI/KPAH) may remain MVFR
through much of the day. Light and variable winds will take on
more of NNE component on Tuesday.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...08
SHORT TERM...ATL
LONG TERM...Smith
AVIATION...SP
Area Forecast Discussion
National Weather Service Springfield MO
710 PM CDT Mon Mar 16 2020
.SHORT TERM...(This evening through Tuesday)
Issued at 146 PM CDT Mon Mar 16 2020
The main forecasting concern overnight is fog development along
the Ozark Plateau, where visibility may reduce below one mile...
At 18z, GOES WV imagery revealed a deep upper-level closed low
spinning over the west coast. In the mid-levels, deep southwest
flow was spreading across the dessert southwest and into the
southern Plains with embedded shortwave energy ejecting towards
the Missouri Ozarks. Meanwhile, in the low-levels, a moisture-
laden air mass remains in place as moisture from both the Pacific
and the Gulf continue to advect into the region.
BUFKIT modeled soundings for the rest of this afternoon indicate a
shallow moisture depth with little or no cloud condensation
nuclei. Therefore, the main precip mode going into early evening will
be patchy drizzle with perhaps some scattered light rain mixing
in at times. However, we cannot rule out a thunderstorm beyond
00z as RAP analysis shows the re-emergence of some cloud ice, as
well as a few hundred J/kg of MUCAPE. Any convection would be
elevated and very isolated, and would likely occur south of I-44.
As a diffuse cold front passes through overnight and winds turn
light and northerly in its wake, areas of fog and patchy drizzle
will develop along the Ozark Plateau with the help of some
orographic lift. HiRes models are showing visibility below 1 mile
in some spots along the plateau by Tuesday morning.
Temperatures overnight will be near 40 degrees.
No sensible weather is anticipated during the day on Tuesday as
surface high pressure quickly builds across the Ozarks. By the
afternoon, surface winds will have veered to the south as the
center of high pressure moves into the Great Lakes region and a
pre-frontal trough lifts into the Plains. The net effect will be
temperatures into the 60s as warm air advects into the Ozarks.
By Tuesday night, rain begins to spread back into eastern Kansas
as a negatively- tilted shortwave trough lifts in here on the nose
of a 300-mb 100 kt speed max. There will be little or no
instability Tuesday night into Wednesday, so no mention of thunder
has been made during that timeframe.
Temperatures Tuesday night will remain mild with overnight lows
near 50.
.LONG TERM...(Wednesday through Monday)
Issued at 146 PM CDT Mon Mar 16 2020
The focus then turns to mid-week as the flooding and severe
weather threats begin to ramp up.
By Wednesday morning, a strong upper-level trough begins to pivot
into the Four Corners region, taking on a negative tilt. Meanwhile
across eastern Kansas and the Missouri Ozarks, all severe weather
ingredients will come together as a surface warm front lifts into
the region. Dewpoints will surge into the 60s across the warm
sector as MLCAPE increases to 1000-1500 J/kg. A quick glance at
the BUFKIT model soundings reveal steepening mid-level lapse rates
and strong deep-layer directional shear on the order of 40-50
kts. Aided by backed surface winds along the warm front,
thunderstorms will become likely by afternoon with all severe
weather hazards possible.
Temperatures on Wednesday will surge into the 70s.
Another round of rain, perhaps heavy, will come Thursday. The
severe weather threat will be held in check as excessive cloud
cover limits the available instability. Still, synoptic lift will
be robust as the nose of a 100-120 kt 300-mb jet max enters the
Ozarks. This will help PWATs on the order of 1.5-1.8 inches be
fully realized. Current NBM 50-75% guidance is showing between
2-4 inches of rainfall between Wednesday afternoon and Thursday
night. This will certainly lead to flooding given the wet
antecedent conditions.
Friday will be sharply colder as a strong cold front passes
through the region. Wind Advisory criteria may be met Friday
morning before the strong frontal system lifts out of the area. A
dry period commences this weekend as a modified Canadian high
settles in. Temperatures during this time will be 10-15 degrees
below normal.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 657 PM CDT Mon Mar 16 2020
Increasing fog tonight will lead to reduced visibilities and
ceilings into Tuesday morning. May need to go with lower
visibilities at KSGF, but will keep an eye on that.
At least some improvement to ceilings is expected through the day
Tuesday, with potential for larger improvements to high-end MVFR
or VFR around the end of this TAF period.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Albano
LONG TERM...Albano
AVIATION...Titus