Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/26/23
Area Forecast Discussion
National Weather Service Cheyenne WY
728 PM MDT Wed Oct 25 2023
.UPDATE...
Issued at 722 PM MDT Wed Oct 25 2023
HiRes model guidance has been consistent with the 00z update
showing high winds across Carbon County with the arrival of the
cold front tomorrow, and gaining traction with the NBM v4.1
Probability of Exceeding 48kts indicating a higher likelihood of
for criteria winds for the current zones in a High Wind Watch. As
a result, went ahead and upgraded the High Wind Watch to a High
Wind Warning for tomorrow afternoon through tomorrow evening, as
the front will likely increase wind speeds across the zones.
&&
.SHORT TERM...(Rest of Today through Friday night)
Issued at 253 PM MDT Wed Oct 25 2023
KEY Messages:
* Strong gusty winds will develop across Carbon County tomorrow
afternoon. A High Wind Watch remains in effect for the threat of
wind gusts in excess of 60 mph.
* A fast moving and cold trough will push a strong cold front and
the threat of widespread rain/snow showers to the region.
* Much colder temperatures expected Thursday night and Friday.
Lingering low stratus clouds across the Nebraska Panhandle have
kept temperatures on the cool side, especially across the Sidney
area. Sharp clearing continues slowly across the Nebraska
Panhandle with temperatures quickly rebounding once the cloud deck
erodes. The rest of the forecast for today remains unchanged as
we continue to track the incoming storm system.
Thursday continues to be the beginning of the transition from
warmer and drier weather to unsettled weather and much colder.
Latest analysis shows the surface front still semi stalled out
across southern Canada with both the upper level cold front and
main trough axis moving through the Intermountain West. Slight
changes were noted in the models as the overall speed of the
trough axis as slightly slowed down and this will overall have a
net effect on when the transition of rain to snow occurs mainly
for areas east of the Laramie Range.
The first impact from the the storm system will be a corridor of
strong winds that develop across Carbon County Thursday afternoon.
The current High Wind Watch remain in effect but parameters are
coming together that has increased confidence that an upgrade to a
High Wind Warning may be needed across these areas. Deep cold air
convection intrusion behind the main surface cold front pair with
adequate QPF that bands of rain/snow showers will develop along
and just prior the main frontal boundary. While the motion has
slightly slowed down, the overall mean flow still remains rather
fast so the duration of the precipitation still looks to be rather
short but with longer duration of snowfall with the later
transition to snow. Still expecting minimal impacts regarding the
accumulating snowfall across the region with the highest totals
still remaining across the higher terrain. The other noticeable
impact will be the much colder temperatures as temperatures will
crash into teens across much of the region.
.LONG TERM...(Friday through Tuesday night)
Issued at 233 AM MDT Wed Oct 25 2023
Active weekend of weather in store with cold temperatures and
chances for rain and snow showers. Models overall have trended the
trough from a cutoff low to more of a positively tilted open wave
that swings through Friday night through Saturday. There are still
significant discrepancies between model solutions, so confidence is
still low to medium on exact impacts to southeast Wyoming and the
Nebraska panhandle. The cold front is forecast to reach central
Wyoming Friday evening, entering the Nebraska panhandle by late
Friday night. Precipitation will likely be along and just behind the
frontal passage. At lower elevations, precipitation may begin as a
light rain/snow mix, transitioning to all snow as the colder
temperatures set in behind the front. One of the main changes from
yesterday`s forecast package is that many of the GFS and ECMWF
Ensemble members have trended the trough and better moisture further
south, so the heaviest snowfall has trended further south, centered
along the Interstate-80 corridor. In addition, due to the Laramie
Valley having primarily easterly, downslope flow throughout this
event, trended the total snowfall and QPF down there. On the other
hand, the easterly flow is upslope for areas east of the Laramie
Range, so the snowfall totals trended upward along the Cheyenne
Ridge and the central to southern Nebraska panhandle. Due to the
continued changes in track of this trough though, confidence is low
in snowfall totals. The highest confidence for this event is in the
temperatures expected. Forecast high temperatures Friday are in the
upper 30s to 40s, which is around 10 to 15 degrees below normal.
After the cold front moves through Friday night, high temperatures
Saturday and Sunday are in the 20s and 30s, which is 20 to 30
degrees below normal for the end of October.
Monday, the trough ejects eastward, bringing ridging back to
southeast Wyoming and the Nebraska panhandle. Dry conditions with
gradual warming temperatures expected through Tuesday. The key word
is "gradual," high temperatures will still be in the upper 30s to
mid 40s with lows in the teens to low 20s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 514 PM MDT Wed Oct 25 2023
Expecting another round of IFR/LIFR stratus and fog for the
Nebraska Panhandle airports this evening. Looking at visible
satellite imagery...low clouds are just east and south of KSNY and
KAIA at 23Z this afternoon. Expect this stratus to surge west
after sunset with low clouds at both airports. Eventually the low
clouds make it into KBFF and KCDR towards 06Z. Used latest HRRR
guidance for timing. Elsewhere...front approaches KRWL Thursday
afternoon with snow developing near Rawlins.
&&
.FIRE WEATHER...
Issued at 240 PM MDT Wed Oct 25 2023
Main fire weather concern today will be the gusty
winds across Carbon county but relative humidity values should
remain above fire weather criteria. Fire weather concerns will
remain low beginning tomorrow through the weekend as a cold and
wet storm system will bring widespread rain/snow showers and much
colder temperatures to the region.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...High Wind Warning from 3 PM Thursday to midnight MDT Thursday
night for WYZ109-110-113.
NE...None.
&&
$$
UPDATE...MRD
SHORT TERM...AW
LONG TERM...LEG
AVIATION...GCC
FIRE WEATHER...AW
Area Forecast Discussion
National Weather Service Glasgow MT
251 PM MDT Wed Oct 25 2023
.DISCUSSION...
...First widespread snowstorm of the season continues for the
region...
AFTERNOON DISCUSSION:
Current radar imagery from KTFX shows that reflectivities have
come down in the last few hours. From KGGW, lower reflectivities
are starting to move into Petroleum County. Since this morning, a
narrow band of moderate snowfall developed from near the Winnett
area northeastward toward Poplar. The edge of moderate snowfall
now appears to be in McCone County and will continue to move to
the northeast. Along the International Border, snow showers are
starting to pick up, but will also be shorter in duration than the
bands south of the Missouri River. A freezing rain/light snow mix
has been producing icy conditions along the I-94 corridor this
morning and into the afternoon. As of this morning, the
probability of ice accumulations exceeding a tenth of an inch
ranges from 20-30%. The Latest RAP mesoanalysis over Prairie,
Dawson, and Wibaux Counties shows 850mb temps already dropping to
below freezing as cold air advection moves in from the
north/northeast. As such, any mixed precipitation should come to
an end this evening. Given this trend today, there was no good
reason to adjust any of the winter headlines for the remainder of
the day.
Overnight, the second round of this winter storm event will get
underway (primarily after midnight). The latest hi-res models
continue to lock into the main snow band developing across
southeast Montana into southwestern North Dakota. The core of
forecast snowfall amounts will remain south of the CWA. Given the
proximity to the gradient of heavier amounts, locations in
Prairie, Dawson, and Wibaux Counties may expect heavier amounts
should a heavy snow band moves over head. 12Z HREF is also hinting
at snowfall rates in these heavy snow bands up to one inch per
hour. But overall, the greatest totals remain south of the CWA.
Thursday morning, the main snow band will continue over southeast
Montana, while more widespread lighter snow showers expands in
coverage through the rest of the CWA. By Thursday evening, the
snow will end from the west and coming to an end around
midnight/early Friday morning. I won`t adjust the end time of the
winter headlines, but will pass this along to the evening/midnight
crew to see if an adjustment will be warranted given the latest
model run.
The region remains under a trough influence through Saturday,
switching to a more northwesterly flow as the trough moves over
towards the Great Lakes and a ridge builds along the US West
Coast. This will keeps highs below normal through mid-week next
week.
-Enriquez
&&
.AVIATION...
UPDATED: 2030Z
FLIGHT CAT RANGE: MVFR - LIFR
DISCUSSION: Moderate snowfall is winding down for locations east
of KGGW. Light snowfall expected to come to an end through the
evening. After midnight, a snow band will develop south of I-94
corridor. At times, heavy snowbands will reduce flight categories
down to LIFR. Thursday, more widespread light snow showers
throughout northeast Montana.
WIND: Northerly at 10-20kts for KGDV and KSDY. Elsewhere,
northerly winds at 10-15kts. After midnight, expect northerly 5-10
west of KGGW and northerly at near 10kts at KGDV and KSDY.
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 6 AM MDT Friday for Central and
Southeast Phillips...Central and Southern Valley...Dawson...
Eastern Roosevelt...Garfield...McCone...Petroleum...Prairie...
Richland...Sheridan...Southwest Phillips...Western Roosevelt...
Wibaux.
Winter Weather Advisory until 6 AM MDT Friday for Daniels...
Northern Phillips...Northern Valley.
&&
$$
weather.gov/glasgow
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
633 PM CDT Wed Oct 25 2023
.UPDATE...
Issued at 437 PM CDT Wed Oct 25 2023
Updated forecast to issue a Dense Fog Advisory. At least four
local observations are reporting dense fog and the fog is expected
to become more widespread during the evening and overnight hours.
&&
...Aviation Update...
.DISCUSSION...(This evening through Wednesday)
Issued at 240 PM CDT Wed Oct 25 2023
Key Messages:
* Patchy dense fog will be possible across the outlook area
through midday Thursday, and may eventually need to consider a
dense fog advisory later this evening if conditions deteriorate
further after sunset and if the denser variety of fog becomes
more widespread.
* Isolated to scattered showers and thunderstorms will continue to
be possible over the next 24-36 hours as additional pieces of
upper level energy cross the local area from the southwest.
* A strong cold front will cross the region from the northwest
late Thursday night, bringing with it the coldest air of the
fall season for Friday and likely persisting through at least
early next week.
* Accumulating snowfall appears a bit more likely...at least north
of interstate 80 on Saturday, although snowfall totals remain
uncertain.
Gloomy skies and occasionally unsettled conditions were observed
across the local area today. Fog has been a bit of a headache, as
areas have flirted with visibilities as low as a quarter of a mile
at times, but so far widespread dense fog has not materialized.
That said, the HRRR has been hinting that after a bit of
improvement late this afternoon, conditions could once again
deteriorate this evening, especially for areas west of Highway
281. Due to some uncertainty, held off on a dense fog advisory
for the time being, but fully recognize that one may eventually be
needed late this evening or overnight.
Continued periods of light showers or very weak thunderstorms are
are expected to continue through the afternoon (all areas) and
possibly evening hours (mainly northeast of the Tri-cities)
Thursday night. This is response to continued pulses of upper
level energy rotating out of the upper level low lifting out of
the desert southwest. While not all areas will receive rainfall,
cloudy/gloomy skies and at least some dampness are expected to be
widespread again tomorrow. As a result, temperatures were brought
down a few degrees, but still may be too optimistic based on this
afternoons readings.
Thereafter the focus will shift west as an upper level wave moving
out of the Rockies ejects into the northern plains late Thursday
night, helping to steer a strong cold front across the local area.
At this time, the very cold temperatures continue to be of the
highest confidence, with a trailing upper level disturbance
potentially providing the first accumulating snowfall of the
season. Overall, confidence continues to increase that this will
be primarily an all snow event, as the atmospheric profile will
have cooled sufficiently ahead of this wave that to warrant mainly
snow. While moisture amounts remain in question, with the type of
precipitation now anticipated to be mostly snow, confidence is
also increasing that a few to a couple of inches of total snowfall
accumulation will be possible in the most favored areas where a
band of snow sets up Saturday afternoon, with global models
indicating about a 40-50% chance for 3 inches of snow or more for
areas mainly northwest of the tri-cities.
Once this wave passes the area Sunday morning, dry weather will
return, but the cold air will linger for several days, with both
morning lows and afternoon high temperatures likely running well
below normal through at least Halloween. A gradual warming trend
thereafter is possible as the upper level flow then shifts more
westerly and a weak ridge tries to push in from the west for the
latter par of next week.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday)
Issued at 628 PM CDT Wed Oct 25 2023
Low ceilings and fog are expected to continue through the
overnight hours and into the morning hours. Rain showers will
continue for this evening. The fog may improve during the later
part of the night. Expect low clouds to continue through the end
of the TAF period although ceilings will improve some during the
afternoon. Winds will remain light and will become northerly by
12z.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...Dense Fog Advisory until 10 AM CDT Thursday for NEZ039>041-
046>049-060>064-072>077-082>087.
KS...Dense Fog Advisory until 10 AM CDT Thursday for KSZ005>007.
&&
$$
UPDATE...Schuldt
DISCUSSION...Rossi
AVIATION...Schuldt
Area Forecast Discussion
National Weather Service Wichita KS
620 PM CDT Wed Oct 25 2023
...Updated Aviation Discussion...
.KEY MESSAGES...
Issued at 316 PM CDT Wed Oct 25 2023
* Heavy rain is expected to continue across south-central and
southeast Kansas this evening into tonight.
* A flood watch is in effect for portions of south-central Kansas
until 1 AM CDT
* High confidence (70-80%) in well below normal temperatures this
weekend into next week.
* Wintry precipitation in the form of rain, sleet, snow, and
freezing rain will be possible Saturday and Sunday.
&&
.SHORT TERM...(This evening through Saturday night)
Issued at 316 PM CDT Wed Oct 25 2023
The upper level shortwave trough that is currently situated across
northern Mexico and the U.S Southwest will slowly shift east this
evening and will eject into the Southern Plains leading to
additional thunderstorm development and heavy rain.
Much of south-central Kansas saw 2 to 5 inches of rain today with
additional rainfall forecasted for the same areas tonight. The RAP
and HRRR both show PWAT values in the 1.25 to 1.5" range, which
would allow for any additional storms to have very heavy rain that
could lead to flooding and localized flash flooding in areas. The
flood watch will be extended 06z Thursday to cover the potential
threat. Further east confidence is high (80-90%) in heavy rainfall.
There will be some localized flooding concern, however much of
southeast Kansas did not get rain this morning, so not as concerned
with the flood potential, especially east of the Flint Hills. As of
now the flood watch won`t be expanded eastward.
A secondary shortwave trough currently located across the Pacific
Northwest will move across the Northern Intermountain Region tonight
and across the Northern Plains Thursday night. This will trigger a
cold front to sweep down the Plains and into our region.
Precipitation is not anticipated to be involved with this cold
front, but strong gusty winds of 35 to 40 mph will be possible
behind the front. Highs on Friday may struggle to get out of the 40s
across central Kansas and the low 50s in southern Kansas.
.LONG TERM...(Sunday through Wednesday)
Issued at 316 PM CDT Wed Oct 25 2023
Global ensembles and deterministic models are in agreement with a
longwave trough taking shape across the western U.S on Saturday and
will shift eastward into the Plains through the weekend into the
week. The setup is a pretty classic shallow cold air with
overrunning precipitation setup. This will allow for the potential
for wintry weather across central and south-central Kansas. P-types
look to be a rain, sleet, and freezing rain mix, but snow can`t be
completely ruled out, especially across central Kansas. For now will
continue to message a rain/snow mix until confidence of P-type
increases.
With this being a shallow cold air outbreak there are a
few things to watch that could lead to significant changes in the
forecasts. First, models tend to underestimate the speed and
magnitude of cold air with these types of setups. This could lead to
a faster changeover in winter weather if that continues to be the
case. Second, with warm surface temperatures, high precipitation
rates would be needed to overcome the warm surfaces for any wintry
accumulations. If higher precipitation rates occur impacts could
become more significant. Finally, timing of the precipitation with
the cold could drastically change the forecast. For example, the 12z
GFS has the bulk of the precipitation fall before subfreezing temps
arrive to much of the area, leading to limited wintry accumulations.
The 12z Canadian, on the other hand has a better overlap of the
subfreezing temps and precipitation, leading to a more impactful
storm. Forecasts should be monitored in the coming days as we
continue to refine the smaller details in how the storm this weekend
will evolve.
Confidence is medium to high (50-70%) in below normal temperatures
extending into the work week. The global models all agree on below
normal temperatures, however they vary on just how cold it may get.
The 12z Canadian and 00z ECMWF both have well below normal
temperatures with reinforcing shots of cold air while the GFS shows
below normal temperatures, but is much closer to a far lesser
extent. Will continue to forecast below normal temperatures until
confidence increases in how extreme the cold will be.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 614 PM CDT Wed Oct 25 2023
Rain is gradually tapering off across the area, but another round
of moderate rainfall with possibly some occasional thunder is
expected across portions of southeast Kansas tonight. MVFR to IFR
vis cats are possible at KICT and KCNU with the additional
rainfall tonight. Also, MVFR to IFR cigs are expected across the
entire area though the morning hours on Thursday before ceilings
gradually rise from west to east during the day on Thursday.
After 09Z, rain is expected to move eastward, and conditions
should gradually improve after that point.
&&
.PRELIMINARY POINT TEMPS/POPS...
Wichita-KICT 62 77 48 56 / 70 20 0 0
Hutchinson 61 77 45 52 / 50 10 0 0
Newton 62 76 47 55 / 80 20 0 0
ElDorado 63 76 50 59 / 90 20 0 0
Winfield-KWLD 64 78 52 63 / 90 20 0 10
Russell 60 77 39 49 / 30 0 10 0
Great Bend 60 77 40 50 / 30 0 0 0
Salina 62 79 43 51 / 50 10 10 0
McPherson 61 76 43 51 / 50 10 0 0
Coffeyville 65 77 59 72 / 90 70 10 30
Chanute 64 75 54 69 / 90 70 10 20
Iola 64 75 52 69 / 80 60 10 30
Parsons-KPPF 65 76 57 71 / 90 70 10 30
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
Flood Watch until 1 AM CDT Thursday for KSZ052-053-068-069-083.
&&
$$
SHORT TERM...CRW
LONG TERM...CRW
AVIATION...JC
Area Forecast Discussion
National Weather Service Norman OK
1044 PM CDT Wed Oct 25 2023
...New AVIATION...
.SHORT TERM...
(This evening through Thursday)
Issued at 239 PM CDT Wed Oct 25 2023
The short-term forecast primarily concerns the potential for
flooding convective rain across southern Oklahoma and adjacent
western north Texas. Regional radar observations show a loosely
organized MCS across the Texas Hill Country. This MCS is lifting
north-northeast and will impact the Red River Counties this
afternoon. A tendency for back-building and slow eastward
translation of the MCS will combine with record-high PWATs to
produce efficient rainfall in this region. Rainfall totals of 1-3
inches with some isolated amounts up to 5 inches are possible in
southern and southeastern Oklahoma before the MCS moves out of the
area overnight.
Humid conditions will continue tomorrow, along with a stiff
southerly breeze. Warmer temperatures aloft will preclude rain
chances, and some breaks in the clouds should get us up to a steamy
day in the low-80s.
Meister
&&
.LONG TERM...
(Thursday night through next Tuesday)
Issued at 239 PM CDT Wed Oct 25 2023
The first of two cold fronts is progged to arrive sometime after
daybreak on Friday. This front should sweep through most of the area
by Friday evening. There are some model disagreements on the degree
of impact of this first front. The HRRR suggests ample instability
in advance of it and potentially a highly forced line of convection
along the front. Most other models remain dry, but the NAM maintains
a cold and cloudy postfrontal airmass, while some other models try
to clear things back out by Friday afternoon. Went with a 50-50
blend of the NAM and other guidance on high temperatures under the
expectation that postfrontal stratus remains a bit longer than
global models expect.
A more widespread rain event is expected to begin on Saturday and
last through Sunday. Because of this, and with breezy north-
northeast winds expected to continue, much-below-average
temperatures are likely through the area over the weekend. On
Saturday, a warm nose will develop as southwest flow aloft continues
to advect warm 700 mb air in, with a cooler surface layer. Some
models indicate meager instability aloft, and in the face of
moderate isentropic ascent the rain that does occur may be partially
convective in nature and occasionally occur in cellular form rather
than pure stratiform rain.
A reinforcing shot of cold air will arrive Saturday night into
Sunday. Here is where solutions really begin to diverge. Most
guidance (including the LREF ensemble, which only gives a 35% chance
of temperatures reaching 32 in northwest Oklahoma and a less than
10% chance of getting below 28) keep temperatures above freezing
during the period early Sunday when precipitation is likely to still
be ongoing. Given the fact that rain will be falling as this cold
shot arrives, this seems plausible. However, given the well-
established practice of shallow cold airmasses trapped beneath warm
noses to remain colder than all guidance, have decided to leave the
NBM temperatures for Sunday morning in place, and those introduce a
wide region of subfreezing temperatures. NBM was also suggesting the
potential for some sleet and freezing rain (naturally, given the sub-
freezing temps and warm nose aloft). Kept some potential for
freezing rain, but only in the northwest corner of Oklahoma where
LREF ensemble probabilities suggest a plausible chance of getting
cold enough. Right now, the chance that we get cold enough for sleet
seems unlikely.
Precipitation will taper off on what will be a downright cold Sunday
afternoon. Monday morning will be the coolest of the year so far for
our forecast area, and widespread frost/freeze headlines are likely
going to be necessary.
&&
.AVIATION...
(06Z TAFS)
Issued at 1042 PM CDT Wed Oct 25 2023
Few changes were made to the 06Z TAFs. Low cigs have already
developed across western OK, and will continue to expand
overnight. MVFR to IFR cigs and vsbys will likely impact all of
the terminals through ~15Z Thursday. The lowest visbys are
expected over CSM. Flight conditions should improve greatly after
17Z Thursday for all terminals, although south winds will be a bit
breezy.
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 73 64 78 60 / 90 60 0 0
Hobart OK 74 60 81 56 / 100 30 0 0
Wichita Falls TX 77 64 83 66 / 80 60 0 0
Gage OK 76 56 84 46 / 70 10 0 0
Ponca City OK 73 62 79 55 / 70 50 0 0
Durant OK 82 66 80 68 / 50 100 60 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Flood Watch through Thursday afternoon for OKZ025-027>032-
039>043-045>048-050>052.
TX...None.
&&
$$
SHORT TERM...04
LONG TERM....04
AVIATION...03
Area Forecast Discussion
National Weather Service Shreveport LA
847 PM CDT Wed Oct 25 2023
...New UPDATE...
.UPDATE...
Issued at 840 PM CDT Wed Oct 25 2023
A few rogue showers continue to slowly drift N/NW across parts of
extreme NW LA early this evening while a more concentrated area of
convection is noted along our far western edge of NE TX and SE OK.
Given these recent radar trends, did make minor adjustments to the
PoP forecast through the remainder of this evening, but otherwise
all other elements appear to be trending as expected with better
coverage of showers and isolated thunderstorms across our NW zones
after midnight. So aside from those minor changes, the inherited
forecast was maintained for the remainder of the overnight hours.
Updated text products have been issued.
/19/
&&
.SHORT TERM...
(This evening through Thursday Night)
Issued at 308 PM CDT Wed Oct 25 2023
The cu field is finally beginning to show signs of scattering out
to some extent across the region this afternoon, with increased
insolation and warm advection yielding another very warm and humid
afternoon. While some decrease in the cu field is expected over
portions of N LA this evening, a 30-40kt Srly LLJ will yield
additional redevelopment overnight, with cigs lowering as well,
especially as the sharp upper trough now over Cntrl NM/far W TX
near ELP, begins to eject NE through W TX this evening, and into
Wrn OK/WCntrl TX by daybreak Thursday. Convection development
ongoing just E of the TX Big Bend region is expected to expand
this evening as large scale forcing increases ahead of the
approaching trough axis, with a mostly linear area of deep
convection containing heavy rainfall continuing to spread NE
through NCntrl TX into Cntrl/NE OK along the SSWrly LLJ axis.
While isolated -SHRA will remain possible mainly over the SW
sections of Deep E TX late this afternoon, the great concentration
of convection should remain just off to the W this evening,
before slowly spreading E into extreme SE OK, adjacent SW AR, and
the Wrn sections of E TX overnight.
Forcing ahead of the trough is expected to weaken though as the
trough axis shifts NE of the area over the Ozarks shortly after
daybreak Thursday, which will result in a weakening trend of the
convection as it enters the region. The HRRR remains most
aggressive with the Ewd advancement of the convection, suggesting
the most momentum, but believe it may be a bit too fast compared
to the other CAM solutions and 12Z NAM/GFS, although continued
scattered convection redevelopment will remain possible especially
as the higher PW air spreads NE into the Wrn half of the area, and
the mean flow becomes more unidirectional/SWrly. Did not deviate
too much with the current pops, maintaining categorical pops in
the morning NW of the I-30 corridor but did taper back pops
slightly to likely across much of E TX/SW AR as the various progs
weaken the approaching convection quickly. Should see quite a
range in max temps from W to E Thursday afternoon, with the Ern
zones seeing temps just shy of 90 degrees (and record territory).
Scattered -SHRA will continue across much of the region Thursday
night as additional weak perturbations focus redevelopment along
the SWrly unidirectional flow. QPF amounts will remain light
though, with chance pops persisting across the Wrn half of the
area. Unfortunately, the greatest rainfall amounts will remain
over areas which have observed plentiful rain as of late, with the
more significant drought-stricken areas of Deep East TX into N LA
seeing only minimal amounts which will not alleviate drought
conditions in place.
15
&&
.LONG TERM...
(Thursday night through next Tuesday)
Issued at 228 PM CDT Wed Oct 25 2023
The long term period can succinctly be described as a series of
unsettled, wet, warmer than average days followed by a precipitous
cool down to conclude October. By early Friday, the pattern
established midweek will be very much still in action, with a series
of disturbances pressing into the northwestern ArkLaTex as they ride
southwesterly flow aloft on the leading edge of a vast area of
troughing aloft over the western CONUS. Meanwhile, the stubborn area
of high pressure over the Gulf Coast and much of the Deep South will
be beginning to stretch as it struggles to maintain its
organization, but it will hold on long enough to inhibit rainfall
across our north central Louisiana parishes for another day and a
half or so.
Beginning Friday, the potential looks to be setting up for some
regions to experience areas of flash flooding after several
subsequent days of heavy rainfall. The most at risk zones will be
those which receive repeat rainfall events, particularly along and
north of the I-30 corridor, but a Marginal Risk for Excessive
Rainfall expands to cover much of the Four State Region Sunday.
By late Saturday, one of the upper level disturbances will organize
itself into a deepening trough ejecting east from the Front Range in
to the Plains, dragging with it a potent cold front which will kick
up more widespread chances of rainfall ahead of its initial passage.
Rainfall will increase during the day Sunday, lingering areawide
into Monday before finally clearing the entire region by the early
hours Tuesday. The initial passage of the front, along will what
appears to be a sustained period of steady trailing stratiform
rainfall, will significantly inhibit warming, with lows dropping
into the upper 30s to near 50 Monday morning, followed by high
temperatures in the 50s during the day Monday.
After rainfall clears the area by early Tuesday, colder air will
invade the ArkLaTex in force, with more lows in the 30s to lower 40s
Tuesday morning, followed by daytime highs in the 50s under clearing
skies on Halloween. Overnight Tuesday into Wednesday looks to see
the coldest lows of the autumn so far. This remains far enough out
in time to refrain from advertising specific details at this time,
but latest model runs suggest some of our northern sites may have a
shot at seeing their first freeze next week. Precise temperature
details may well fluctuate in the coming week, but suffice to say a
significant cool down is on its way, and any prospective trick or
treaters may want to start exploring some warmer options for their
costumes this year.
/26/
&&
.AVIATION...
(00Z TAFS)
Issued at 718 PM CDT Wed Oct 25 2023
For the 26/00Z TAF period, VFR conditions are observed to begin
the period but expect a gradual return and expansion of stratus
and stratocu on Thursday morning, resulting in MVFR cigs across
much of our airspace by around 26/09Z and thereafter. Gradual
improvement of these cigs is expected between 15Z-18Z as some
scattered convection begins to expand eastward across our East TX
terminals. KTXK/KSHV could also be impacted by this convection
later on in the afternoon, but confidence is lower as you move
farther east due to the strength of an upper-level ridge oriented
along the central/eastern Gulf coast and much of the SE CONUS.
Otherwise, look for low VFR cigs to eventually return late in the
period with S/SE winds generally ranging from 5-10 kts with some
occasional higher gusts on Thursday afternoon.
/19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 71 84 72 83 / 20 50 40 40
MLU 65 88 70 86 / 10 10 10 20
DEQ 68 76 68 79 / 40 70 50 60
TXK 68 78 69 79 / 20 60 50 60
ELD 66 84 69 81 / 10 40 30 40
TYR 72 79 71 82 / 30 70 40 50
GGG 70 81 70 83 / 20 60 40 50
LFK 71 84 69 83 / 20 60 40 50
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
SHORT TERM...19
LONG TERM....26
AVIATION...19
...Update to aviation forecast discussion...
.DISCUSSION...
Issued at 304 PM CDT Wed Oct 25 2023
Key Points:
- Rain continues with a few embedded thunderstorms through tonight.
Another 1-2" is expected, with any additional rainfall exacerbating
flooding concerns along the I-35 corridor.
- Drying conditions by Thursday afternoon, then a much colder air
mass moves in Friday and sticks around into next week
- Increasing chances for precipitation Saturday into Sunday,
including potential for wintry precipitation
19Z water vapor imagery depicts an upper trough axis swinging out of
northern Mexico and into west TX with plenty of moisture streaming
northward out of that trough through OK and into eastern KS. The
next upper low is circulating over the Pacific Northwest. Meanwhile
at the surface, a boundary sits in northern KS near the Hwy 36
corridor, which extends out of the sfc low centered in the TX/OK
panhandles. This set-up has kept our area in the trajectory for
continued rainfall throughout the day with record Pwat values, as
this morning`s 12Z sounding set another record for that date and
time at 1.59". The bulk of the remaining rainfall should push
through the area this afternoon and this evening before starting to
taper off later tonight. The LLJ looks to shift east into MO after
midnight, keeping most rain east of us during the overnight hours
aside from some isolated to scattered showers west. The HRRR and RAP
then have another round moving through eastern KS Thursday morning
as the upper trough axis swings across the area, whereas other CAMs
appear less robust with this activity. In any case, east central KS
is the prime location for each additional round of rainfall with
another 1-2" forecast, although locally higher amounts may still be
possible. Flash flood guidance is naturally much lower in the I-35
corridor from Emporia to Ottawa, where 5-10" of rain have fallen
since last evening. As such, it wouldn`t take much more rainfall to
cause additional flash flooding. While other areas could see up to
an inch in an hour, soils should be able to take the rain without
issue.
Thursday afternoon and evening looks to dry out as the trough axis
moves east of the area. The aforementioned Pacific system then looks
to move across the northern part of the country and push a strong
cold front across the area. Recent trend has been for this front to
pass a little faster, having moved through by late Friday morning
and leading to falling temperatures through the 40s and 50s through
the day. Upper troughing dominates the western CONUS this weekend
into early next week, with another wave looking to bring another
round of precipitation Saturday into Sunday. While uncertainty
remains with precipitation types and amounts, there is still
potential for wintry precipitation particularly toward north central
KS. What looks more certain is for morning lows to drop below
freezing in north central KS Sunday morning and the entire area
Monday morning, with ensemble data indicating an 80-90% chance of
this occurring, which would officially end the growing season across
the CWA. Highs look to remain in the 40s and 50s with lows in the
20s and 30s through Wednesday of next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 620 PM CDT Wed Oct 25 2023
Scattered rain showers will continue for the first portion of the
TAF period with CIGs bouncing between IFR and MVFR. There should
be a brief break in precip before another round of rain and
isolated storms move into KTOP and KFOE by early Thursday morning.
CIGs should lower to low end MVFR to high end IFR as precip
impacts the terminals. Opted to keep mention of VCTS out of KMHK
as confidence in storms forming that far west is not high.
Ceilings will recover to VFR status by late Thursday morning and
afternoon as rain moves off to the east.
&&
.CLIMATE...
Updated at 358 AM CDT Wed Oct 25 2023
Record and forecast highest minimum temperatures:
Wednesday, October 25:
City Forecast Record(Year)
Topeka 63 63(1939)
Concordia 61 61(1902)
Thursday, October 26:
City Forecast Record(Year)
Topeka 65 61(1900,1989,2004)
Concordia 57 60(1985)
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...Picha
AVIATION...Griesemer
CLIMATE...65/Flanagan