Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/18/22
Area Forecast Discussion
National Weather Service La Crosse WI
1102 PM CDT Tue May 17 2022
.DISCUSSION...(Tonight through Tuesday)
Issued at 228 PM CDT Tue May 17 2022
Key Messages:
- Strong to severe storms possible Thursday night into Friday
- Cooler this weekend
A few short wave troughs to work with in the near term, including
one that has well established frontogenetic forcing brushing our
southern counties today. This is coinciding with southerly moisture
transport. The increased moisture and lift will continue to produce
showers for the area tonight into tomorrow morning. The highest
precipitation amounts /0.3-0.6"/ will be along and south of the I-94
corridor. Elsewhere, 0.1-0.3" are expected. RAP and HRRR model
soundings suggest little to no CAPE in the area overnight, so can
expect primarily rain showers.
More favorable conditions for strong storms stays to the southwest
of the area, though a rumble or two of thunder in far SW Wisconsin,
SE Minnesota, or NE Iowa is not out of the question if whatever CAPE
is available can be tapped into. The precipitation is expected to
move out of the area Wednesday evening/night.
Storm chances Thursday night into Friday:
Focus shifts to convective threat going into Thursday night.
While Thursday morning should start off quiet and pleasant, a
digging short wave trough dropping out of Canada will lead to a
changing pattern as the day progresses. Response from this wave will
lead to a fairly narrow but rapid return of low level moisture
northward along an approaching cold front. This is seen well in
moisture transport fields and model mixed layer CAPE fields
streaming northeast ahead of boundary reaching in excess of 1500
J/kg. Confidence is lower in how far north higher dewpoints may get
attributing to these values. Could be a hint of a warm front in
there as well, likely advecting northeast as the day goes on.
Based on the strength of the wave certainly see the possibility of
strong to severe storms as front comes in Thursday night. Timing
seems a bit more delayed than previous forecasts so this may work
against the overall threat. But given dynamics of stronger wind
field, convection could still be potent with a wind or hail threat
from late evening into the overnight hours. See Day 3 Storm
Prediction Center for other details on risk.
Convection will work east early Friday morning as front clears the
area. Medium range guidance a bit varied in how far north any
precipitation may form along this so will keep in small chances but
gut tells me this will likely remain south of the immediate area.
Weekend and early next week / Cooler weather:
The big story will be the cool down in temperatures for the weekend
as longwave troughing builds into the northcentral CONUS. Highs will
be in the 50s with some freeze possibilities Sunday and Monday
morning at least in the central Wisconsin cold spots.
Saturday could still bring some rain chances it appears. There are a
group of model solutions that stripe a post-frontal frontogenetic
rain band through southern WI...so 30-40% rain chances remain there.
Otherwise, a few instability showers may be around, or at least
diurnal stratocumulus.
A general warming trend begins on Monday in a fairly swift
progressive zonal flow as a series of shortwave troughs shift
through. On and off shower chances into midweek look reasonable with
storm chances returning later Tuesday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1102 PM CDT Tue May 17 2022
Rain showers will continue through most of the overnight hours.
However, MVFR ceilings have been slow to develop this evening.
As rainfall continues to moisten the surface and temperatures
slightly decrease overnight, MVFR ceilings are still likely, but
just closer to early morning by 12z. A heavier and more intense
shower passing directly over a TAF site could temporarily reduce
visibilities to MVFR conditions.
Winds will be on the lighter side of less than 10 knots, but
several wind shifts will occur over this forecast period. Easterly
winds will prevail through a majority of the period, but late
morning/early afternoon is when winds will rotate from the west
to then even southwesterly by the evening.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
DISCUSSION...Dahl / Shea / Baumgardt
AVIATION...Peters
Area Forecast Discussion
National Weather Service El Paso TX/Santa Teresa NM
530 PM MDT Tue May 17 2022
.AVIATION...00Z TAF CYCLE
Generally VFR conditions through period with SKC-FEW250, but
there will be more FU creating some areas of BKN040-060 around
KTCS once again starting after 03Z. Could see some VSBY reductions
to around 5SM around Sierra County. Farther south, less confident
with FU causing VIS restrictions, but it is possible and will be
monitored at KLRU and KELP. Winds generally light tonight, 5 to 15
KTs, with similar values continuing into Wednesday. May be brief
and minor LLWS at KELP around 06 to 12Z as winds aloft increase
but values should remain below 30 kts.
.PREV DISCUSSION...250 PM MDT Tue May 17 2022...
.SYNOPSIS...
Warm and dry weather with breezy afternoon west winds will
persist through the end of the work week. Afternoon west winds
will strengthen Thursday and Friday, becoming gusty in the higher
terrain. Elevated to critical fire weather conditions for most
areas Thursday and Friday afternoon. A backdoor cold front will
move through the area this weekend and cool temperatures down.
Nocturnal east winds overnight will increase moisture values area
wide Sunday through Tuesday, with afternoon west winds scouring
out the moisture during the day.
&&
.DISCUSSION...
.SHORT TERM...Tonight and Wednesday...
Pretty quiet in the short term with a persistent surface low over NE
NM which will keep a little pressure gradient over the area which
could keep overnight lows mild again tonight, especially on eastern
mountain slope locations. Most areas should fall back into the mid
50s to mid 60s. Smoke could be a bigger issue than last night over
Sierra and northern Dona Ana counties looking at the HRRR Smoke
model. Kept mention of patchy to areas of smoke across these
locations.
For Wednesday, surface winds remain westerly but lighter than today
as a weak ridge moves into the region. Besides some morning smoke
lingering, should see another sunny day. High temperatures look
similar to today with highs mainly in the lower to mid 90s over the
lowlands with 70s and 80s in the mountains.
&&
.LONG TERM...Thursday through Wednesday...
A shortwave trough with a weaker closed low will approach the
NM/AZ border early Thursday morning. At the same time, stronger
upper level westerly winds over the Rockies will induce a lee side
trough in CO. The surface pressure gradient will strengthen over
the area Thursday. The upper level short wave will dig too far
south to impact the area, keeping stronger winds aloft out of the
CWA for the most part. Southwest winds will still become breezy in
the afternoon hours for most of the area. As the air remains dry
and warm, fire weather concerns build for Thursday afternoon.
Temperatures will remain around 5 to 10 degrees above normal and
skies clear.
Friday, a broad and large upper level ridge starts to drop south,
increasing upper level winds above the northern parts of the CWA.
The lee side trough will shove southward over northern NM Friday
afternoon from a surface cold front moving down the plains. Winds
Friday afternoon will be breezy to windy with gusts possible in
the higher terrain areas of Gila Wilderness and Sacramento
Mountains. Critical fire weather conditions will continue Friday
with the air remaining dry. As pressure heights above the
southern part of the CWA drop, temperatures will cool to near
normal for most of the lowlands Friday.
Saturday, the backdoor cold front will approach the area.
Deterministic guidance is in strong agreement that the boundary
will stall near the Sacramento Mountains for most of Saturday.
This is due to westerly winds aloft over the western part of the
CWA persisting and mixing heights rising in the afternoon hours
to mix those west winds down to the surface. Overnight into
Sunday morning, the cooler airmass will surge westward increasing
humidity values temporarily. Sunday will be cooler with
temperatures around normal or a few degrees below. West winds will
reestablish later in the afternoon, but east winds will dominate
again over night into Monday morning.
For next week the deterministic guidance starts to disagree. More
shortwaves will pass through the area, increasing winds in the
afternoon hours with easterly winds brining in more moisture
overnight. Precipitation chances are slim as the moisture scours
out during the day, however temperatures will remain near normal
through mid week next week.
&&
.FIRE WEATHER...
Not much change in the weather pattern through the end of the week
with temperatures remaining above normal and winds out of the west.
Tomorrow will see winds drop off a little bit before starting to
increase for the end of the week when near critical conditions are
likely. High temperatures will continue to be above normal with
highs in the 90s for the lowlands. A back door cold front moves in
this weekend which will drop highs about 3 to 5 degrees and also
bring in some higher dew points to at least eastern zones and min
RH`s into the 10-15% range early next week. No precipitation on the
horizon.
&&
26-Grzywacz
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 68 96 63 96 / 0 0 0 0
Sierra Blanca 67 92 60 91 / 0 0 0 0
Las Cruces 60 94 59 95 / 0 0 0 0
Alamogordo 57 94 58 95 / 0 0 0 0
Cloudcroft 45 73 48 72 / 0 0 0 0
Truth or Consequences 61 93 61 95 / 0 0 0 0
Silver City 58 85 57 84 / 0 0 0 0
Deming 55 94 54 93 / 0 0 0 0
Lordsburg 56 91 53 90 / 0 0 0 0
West El Paso Metro 65 95 63 95 / 0 0 0 0
Dell City 55 96 53 96 / 0 0 0 0
Fort Hancock 63 97 58 98 / 0 0 0 0
Loma Linda 60 89 59 88 / 0 0 0 0
Fabens 65 97 60 96 / 0 0 0 0
Santa Teresa 60 94 58 93 / 0 0 0 0
White Sands HQ 68 94 65 94 / 0 0 0 0
Jornada Range 50 93 57 93 / 0 0 0 0
Hatch 58 96 58 94 / 0 0 0 0
Columbus 64 95 60 93 / 0 0 0 0
Orogrande 60 95 59 95 / 0 0 0 0
Mayhill 52 86 53 85 / 0 0 0 0
Mescalero 48 83 50 83 / 0 0 0 0
Timberon 46 81 54 80 / 0 0 0 0
Winston 47 90 50 90 / 0 0 0 0
Hillsboro 60 91 60 91 / 0 0 0 0
Spaceport 53 93 57 93 / 0 0 0 0
Lake Roberts 36 86 48 86 / 0 0 0 0
Hurley 52 87 52 88 / 0 0 0 0
Cliff 42 91 42 93 / 0 0 0 0
Mule Creek 39 87 52 86 / 0 0 0 0
Faywood 56 86 55 88 / 0 0 0 0
Animas 57 92 51 91 / 0 0 0 0
Hachita 55 92 53 90 / 0 0 0 0
Antelope Wells 56 91 54 89 / 0 0 0 0
Cloverdale 53 87 53 84 / 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...None.
TX...None.
&&
$$
99/99/99
Area Forecast Discussion
National Weather Service Goodland KS
528 PM MDT Tue May 17 2022
.UPDATE...
Issued at 524 PM MDT Tue May 17 2022
Storms have formed along a warm front/dryline that is currently
across Northwestern Kansas. A Severe Thunderstorm Watch for
counties along and southeast of a line from Tribune to Greeley
counties has been issued until 11pm MT/midnight CT. These are
counties along and ahead of the line. Hail and strong winds are
expected to be the main threat as this line moves to east across
the next few hours.
Also storms have formed along the Palmer Divide and are moving
east into the area. These storms are expected to move east with
most of them dissipating shortly after the Colorado state line. A
few may continue eastward with latest guidance giving the highest
chances in Southwestern Nebraska. A few storms may produce strong
wind gusts.
&&
.SHORT TERM...(This evening through Friday Morning)
Issued at 234 PM MDT Tue May 17 2022
The main concerns for the short term period are the potential for
severe weather this afternoon and tomorrow afternoon. A developing
low pressure system just off the Front Range is leading to an
increase in a CU field along with a developing storm near Ft.
Collins/Greeley area. The expectation is that this will continue to
move towards the east towards Yuma/Kit Carson county through the
afternoon with the main threat being damaging wind gusts with
inverted v soundings present along with a copious amount of DCAPE
being present. This activity should weaken as it nears or just
after it cross the Kansas state line as we lose diurnal heating.
The other area for potential severe weather appears to be along and
east of a Tribune to McCook line along a weak cold front/wind shift
boundary. A stout CAP is in place but is anticipated to break
late this afternoon as the better forcing from the Colorado low
and convective temperatures are met. A Slight risk from the SPC is
in place where large hail and damaging winds appear to the main
hazard. RAP forecast soundings near Hill City indicate MUCAPE near
2600 j/kg resulting in a high large hail and significant hail
parameter which may support isolated instances of 2+ inch hail. A
caveat to this would be weak 0-6km shear of 25-35 knots will
would support more of a multicell/cluster to develop; as a result
feel the significant hail potential will be reserved to
initiation time frame of 22-00Z unless a dominant more discrete
cell can occur. Due to the rapid upscale development expected am
anticipating more of a damaging wind threat to eventually develop
as storms move to the east out of the CWA around 05-06Z. A couple
hour landspout potential may develop over portions of Cheyenne
County (CO), Greeley and Wichita counties as the cold front/wind
shift boundary appears to be stationary and SPC Mesoanalysis
depicts and overlapping SFC Vorticity/MLCAPE area, this is
dependent on if any developing updrafts occur in this area.
Wednesday, low level moisture returns to east Colorado.
Anticipated strong diurnal heating to result in high based
updraft development along and near the Front Range. Forecast
soundings indicate the potential for 0-6 shear of 25-35 knots
which would result in a multicell convection solutions as
damaging winds would be the main threat with some potential for
large hail with the strongest storms. High temperatures are
forecast to be in the upper 70s to mid 80s across the area, winds
will however be variable around 5-15 mph across the area.
Overnight, lows will be seasonal in the 50s over the the CWA.
Thursday, high pressure develops over the High Plains with gusty
southwesterly winds advecting dry air as RH values approach the
single digits over western portions of the area. Southwesterly winds
of 15-25 mph and wind gusts up to 35 mph look likely across the
majority of the area. After collaboration with surrounding
offices have went with a Fire Weather Watch for counties along and
west of Kansas Highway 27 for Thursday afternoon. As of 5/14 Fire
Weather Fuel Status for the CWA fuels are dry across the entire
area with a few burn bans remaining in place. The potential for
rainfall due today and tomorrows convective potential does exists
which may inhibit short term fire weather concerns, opted to go
for the watch due to the very dry recent conditions and not
making any assumptions on how much rainfall each county may
receive as a widespread rain is not currently expected at this
time. Thursday evening a strong cold front is expected to move
into the area which will allow winds to shift from the SW to the
NE during the evening hours, which would pose the risk for a
rapidly changing wildfire direction if one were to be ongoing.
Cooler temperatures then move into the area behind the front into
Friday morning with overnight lows in the upper 30s across east
Colorado to the low 50s over eastern portions of the area.
.LONG TERM...(Friday through Tuesday)
Issued at 1245 PM MDT Tue May 17 2022
Friday will be breezy and much cooler with high temperatures
ranging from the lower 50s in northeast Colorado to the lower 70s
in Hill City. Upper trough approaching the Rockies will cause
increasing clouds through the day. Precipitation chances start in
northeast Colorado Friday afternoon and spread across the
remainder of the area Friday night, ending Saturday morning. As
temperatures drop into the lower 30s, rain will mix with or change
to snow, mainly in northeast Colorado, but possibly into northwest
Kansas and southwest Nebraska as far east as Highway 25. Models
still aggressively accumulating snow, but with warm ground
temperatures expecting quite a bit of melting. Nonetheless, an
inch or so of slushy accumulation possible during this time. Frost
and freeze highlights will probably be necessary as the growing
season is well under way. Might see some sun Saturday afternoon
and optimistically have highs in the 50s and 60s. Another late
season frost or freeze possible Saturday night as well, mainly
along and west of Highway 25 and into northeast Colorado, as
temperatures drop into the 30s once again.
For Sunday and Monday, another shortwave trough will be moving out
of the northern Rockies and across the central High Plains.
Temperatures will warm into the upper 60s to lower 70s Sunday
afternoon before scattered showers develop Sunday night with the
upper system. Temperatures will be warm enough for all rain this
time around, with lows Sunday night in the 40s. Showers will
continue into Monday morning before ending Monday afternoon. High
temperatures on Monday will be in the upper 60s to lower 70s with
lows Monday night in the 40s. Tuesday currently looks dry as upper
flow turns southwest ahead of the next system digging into the
central Rockies Tuesday night. Downsloping wind component will
allow temperatures on Tuesday to warm to around 80.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 445 PM MDT Tue May 17 2022
For KGLD... VFR conditions are expected through the period.
However, a round of thunderstorms may reach the terminal during
the evening hours (likely between 01-03Z). Ahead of the
thunderstorms, the outflow may kick up blowing dust and reduce
visibility a bit. If the thunderstorms or outflow goes over the
terminal, expect strong wind gusts potentially in excess of 50 kts
and a sudden wind change. After the thunderstorms pass,
relatively quiet conditions and lower wind speeds are expected.
For KMCK... VFR conditions are expected through the period.
However, thunderstorms may move near and through the terminal
closer to midnight local time (around 03-05Z). The blowing dust
potential is not expected to reach the terminal. If the
thunderstorms or outflow goes over the terminal, expect strong
wind gusts potentially in excess of 50 kts and a sudden wind
change. Conditions will then be relatively quiet with winds
reducing in speed.
&&
.FIRE WEATHER...
Issued at 234 PM MDT Tue May 17 2022
Fire weather concerns again return to the area Thursday as
southwesterly flow advects dry and warm conditions back into the
area. High temperatures in the 90s will aid in RH values dropping
to near the single digits across western portions of the area.
Southwesterly winds will gust up to 35 mph as diurnal mixing
increases during the afternoon. Fuels currently remain receptive
for wildfire development, as result a Fire Weather Watch was
issued for counties along and west of Kansas Highway 27 on
Thursday. An advancing cold front during the evening hours will
cause winds to turn the northeast resulting in unpredictable
changing of wildfires if one were to be occurring.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...Fire Weather Watch from Thursday morning through Thursday
evening for KSZ001-013-027-041.
CO...Fire Weather Watch from Thursday morning through Thursday
evening for COZ252>254.
NE...NONE.
&&
$$
UPDATE...KAK
SHORT TERM...TT
LONG TERM...024
AVIATION...KAK
FIRE WEATHER...TT
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1056 PM EDT Tue May 17 2022
.UPDATE...
Issued at 1055 PM EDT TUE MAY 17 2022
The current forecast remains on track so have merely added the
latest obs and trends into the T/Td/Sky grids. These updates have
been sent to the NDFD and web servers.
UPDATE Issued at 800 PM EDT TUE MAY 17 2022
23Z sfc analysis shows high pressure in control of the weather
across eastern Kentucky. The mid level based fair weather cu are
now dissipating leaving behind just some high clouds over the
southwest. Currently temperatures are running in the mid 70s most
places, though some of the valleys have already fallen into the
upper 60s. Dewpoints, meanwhile, are similar to yesterday at this
time - generally in the lower 50s with some mid 50s in the
valleys, amid light winds mostly from the west. Have updated the
forecast mainly to fine tune the sky cover and valley fog threat
through the night. Did also include the latest obs and trends for
the T/Td grids. These updates have been sent to the NDFD and web
servers.
&&
.SHORT TERM...(This evening through Wednesday night)
Issued at 530 PM EDT TUE MAY 17 2022
The latest upper level map features fairly zonal flow west of the
Appalachians, with embedded pockets of traversing short wave
energy. East of the Appalachian chain, troughing is pushing
to the Eastern Seaboard. At the surface, a cold front is draped
from New England through the Ohio Valley, before becoming more
quasi-stationary across the Midwest and through the central
Plains. Meanwhile, a warm front is aligned from the southern
Plains through the lower Mississippi Valley and along the
southeastern CONUS. Modest high pressure is sandwiched in between
these two fronts, generally residing from the central Appalachians
through the middle/lower Mississippi Valley. Eastern Kentucky has
been enjoying plenty of sunshine and another day of lower
humidity, with temperatures currently in the upper 70s and lower
80s at most locations.
The models are in good agreement aloft through the short term,
with zonal flow continuing, with a tighter gradient inbound from
the Pacific Northwest, as a vigorous vorticity lobe makes it way
east across southwest Canada. Further east, an embedded short wave
trough will shift from the Plains through the Ohio Valley by late
Wednesday, with another more prominent upstream wave moving east
southeast across the Great Lakes/Ohio Valley regions Wednesday
night. At the surface, low pressure will generally move east from
the Plains through the Ohio Valley into Wednesday, pulling the
quasi-stationary boundary currently draped across our north
further to the northeast as a warm front. Secondary low pressure
will then move along a quasi-stationary boundary just to the
southwest of the track of the first low, likely being influenced
by mesoscale processes to some degree. By early Thursday, a cold
front will be approaching eastern Kentucky from the northwest.
This all spells a return to stormier conditions across our area by
late Wednesday and especially Wednesday night.
Tonight will feature mostly clear skies, with temperatures
bottoming out in the low to mid 50s in cooler eastern valleys that
take advantage of the drier low level air and calming winds.
Ridges will stay up in the upper 50s, with perhaps some patchy fog
in the river valleys once again, although this should be less
pronounced compared to this morning. Clouds will be on the
increase on Wednesday, with a weakening MCS inbound from upstream.
Depending on how quickly the thicker clouds dissipate,
temperatures could be a little warmer than currently forecast,
generally lower 80s.
The model agreement is good regarding weaker instability initially
across our area through the early afternoon; however as we head
into late Wednesday afternoon and especially Wednesday evening,
CAM guidance varies quite a bit on how vigorous the convection
could potentially be. Have the highest PoPs set up from northwest
to southeast, with PoPs more conditional to the south. The HRRR
is more tame in general; however, the NAM Nest and especially the
NSSL show more potential for severe storms taking advantage of
ample instability (ML CAPE values of 1000-2000 J/kg) and effective
shears(around 40 kts) that will be place, especially west of
I-75, our more typical locations for severe. The main hazards
would be damaging wind gusts and large hail; however, with a
boundary in play, an isolated tornado can not be ruled out as
well.
As we head deeper into the night, more widespread convection is
expected, thanks to an increasing low level jet of 30-40 kts, and
perhaps some influence from traversing short wave energy to our
north. PWATs will increase to around 1.5 inches or slightly
higher. Any leftover mesoscale/convective boundary will likely
align nearly parallel to the steering flow aloft, setting up the
potential of training cells and inevitably a threat for at least
isolated flash flooding. The main question is where this sets up
exactly. Given the lower confidence, will forego a watch for now,
but have beefed up the wording in the HWO. The higher influx of
humidity will keep temperatures much milder overnight, generally
lower 60s.
.LONG TERM...(Thursday through Tuesday)
Issued at 302 PM EDT TUE MAY 17 2022
Lingering showers and possibly a rumble of thunder will be possible
as a cold front slowly exits the region to start the period.
Therefore, Thursday looks to be a warm but potentially a rainy day.
Behind the exiting front, high pressure will build into the region.
This high will bring the return of warmer and drier temperatures for
the end of the week and into the weekend. Widespread temperatures of
upper-80s and lower-90s will be possible but coupled with moist,
southwesterly flow it could be a couple of very uncomfortable days.
Some temperature records could be broken this weekend if this
forecast trend continues. As a split-flow trough digs out of Canada
and the western CONUS, the dome of high pressure will eject offshore
bringing an end to the heat and humidity. However, with the trough
continuing to dig and the associated low moving across the northern
Great Lakes, a strong cold front is progged to move through the area
through the day Sunday. Some timing differences exist with the long-
term models with the GFS bringing the front through Sunday morning
and the ECMWF later in the afternoon. This will be something to pay
attention to because of the severe weather potential and the
potential timing of the front. High pressure briefly builds in again
for Monday before model consensus brings another trough out of the
western CONUS, which will bring more chances for showers and
thunderstorms, for Tuesday into Wednesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 820 PM EDT TUE MAY 17 2022
VFR conditions will prevail through the period, although there
will be another window of MVFR or lower fog possible in the deeper
river valleys between 05 and 12Z. Look for increasing high clouds
and eventually mid-level clouds to move in late in the TAF period.
West to northwest winds of 5 to 10 kts will become light and
variable this evening and continue overnight. Winds will then
pick up to between 5 and 8 kts out of the south southwest by the
mid to late morning on Wednesday.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GEOGERIAN
LONG TERM...VORST
AVIATION...GEOGERIAN/GREIF
Area Forecast Discussion
National Weather Service North Platte NE
620 PM CDT Tue May 17 2022
.SYNOPSIS...
Issued at 341 PM CDT Tue May 17 2022
H5 analysis from earlier this morning had a closed low over
southern Quebec with a trough extending south into the New England
states. A low amplitude ridge was present from western North
Dakota and eastern Montana into northern Saskatchewan and eastern
Alberta. south of this ridge, zonal flow extended from the central
plains west to the Pacific coast. Within this flow, shortwaves
were noted over central Nebraska, as well as western Wyoming.
Further west, closed low pressure was located over eastern
portions of the Gulf of Alaska while a secondary low was located
over Hudson Bay. Thunderstorms had impacted portions of
southwestern into portions of central Nebraska earlier today.
Additional activity passed through the eastern Sandhills and had
cleared the area by noon CT. At the surface, a frontal boundary
extended from near North Platte to Bassett Nebraska. This was more
of wind shift line as temperatures ranged from the middle 70s in
the northeastern panhandle to the middle 80s in far southwestern
Nebraska.
&&
.SHORT TERM...(This evening through Wednesday night)
Issued at 341 PM CDT Tue May 17 2022
The main forecast challenge in the near term continues to be
thunderstorm chances and severe potential tonight. A messy
situation setting up across the area this afternoon with ongoing
convection exiting eastern Nebraska, a frontal boundary draped
across the forecast area and convection beginning to fire off to
the west along the front range of Colorado and Wyoming. The CAMS
including the HRRR continue to differ run to run with their
convective forecast for this evening. This coupled with the
exiting convection in the east, which the models didn`t initialize
with this morning, has made for a low confidence forecast for
tonight. Thinking here is that convection will take on two modes
this evening: The first mode will be elevated convection which
will track east of the front ranges late this afternoon, emerging
onto the western forecast area around 00z tonight. As this
elevated convection and instability hits the cold front, we should
see a second round (second mode) of storms develop during the mid
evening time frame. Based on the latest model guidance, this
boundary will be oriented from McCook to Kearney to Columbus.
Convection may also fire INVOF of a warm front/occlusion in our
far northeastern forecast area. Confidence in this convection
materializing is less certain as this area saw a decent amount of
thunderstorms earlier today and may be less conducive to storm
initiation. With a lack of confidence in the short range models
tdy, will generally go with isolated pops in the central and west
and pops of the scattered variety along the front this evening.
This activity will exit the forecast area by late evening with
some clearing skies expected toward 12z Wednesday. As for severe
mode tonight, large hail and damaging winds will be the main
threats. This is supported by modest DCAPE which is predominately
located over the western Sandhills. As for the large hail threat,
mid level lapse rates are highest along a corridor from far
southwestern into central Nebraska. This is in proximity to the
frontal boundary while the gusty wind threat (highest DCAPE) is
located across the western Sandhills. The tornado threat appears
very minimal across the eastern forecast area given the very weak
low level flow expected tonight. Wednesday and Wednesday night
will see generally benign conditions with a warm front lifting
through the forecast area Wednesday. This feature will stall along
the SD/Nebr. border Wednesday night. I did go ahead and expand
pops across the northeastern forecast area late Wednesday night as
the latest NAM12 and GFS developed some qpf. This seems plausible
given the warm frontal boundary and an increasing low level jet,
the nose of which is positioned from central into northeastern
Nebraska.
.LONG TERM...(Thursday through Tuesday)
Issued at 341 PM CDT Tue May 17 2022
A fairly active pattern will highlight the long term period
across the forecast area. A strong cold front will approach the
forecast area late Thursday. Model differences in frontal timing
will make for a tricky high temp forecast Thursday. MET and MAV
guidance were 93 and 81 for highs respectively for North Platte
Thursday. With the front approaching, and southwesterly winds in
the boundary layer, am weighing the forecast toward the warmer MET
forecast. This agreed with the NBM which had a high of 92 degrees
for a high Thursday. Behind the cold front, much colder temps are
expected with highs in the 50s forecast for Friday and Saturday.
Temperatures Saturday morning and Sunday morning will cool enough
to hit the lower to middle 30s west of a line from Broken Bow to
Ainsworth. Was planning on inserting a mention of frost in the
forecast for all areas. However, the latest GFS, which has some
support from the EC soln, develops a swath of precipitation from
the western Sandhills into southwestern Nebraska Friday night into
Saturday morning. The model even gets cold enough to support some
snow in far SW Nebraska and the eastern Nebraska Panhandle. Not
anticipating any accumulations as soil temps are in the lower 60s
attm. Will leave this to the front ranges and NE Colorado where
snowfall rates will be higher and accumulation potential much
greater. Forcing for precipitation will be in the form of very
strong mid level frontogenesis, so not expecting a lot of wind
Friday night and Saturday in association with the precipitation.
Saturday and Sunday will be dry with a better threat for frost
Sunday morning as cloud cover will be limited compared to Saturday
morning.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 620 PM CDT Tue May 17 2022
Isolated thunderstorms are likely until around 06z this evening,
generally affecting areas along and south of highway 20. The
better chances for storm development will be along and south of
Interstate 80. No storms are expected from 06z tonight through 00z
Wednesday evening.
MVFR/IFR ceilings and vsby in stratus are possible along and east
of highway 183 from 06z this evening through 15z Wednesday.
Otherwise VFR will prevail across wrn and ncntl Nebraska.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Buttler
SHORT TERM...Buttler
LONG TERM...Buttler
AVIATION...CDC
Area Forecast Discussion
National Weather Service Memphis TN
853 PM CDT Tue May 17 2022
.UPDATE...
Not much going on at the moment across the Mid-South and that will
continue through most of the overnight period. A complex of
thunderstorms over the Central Plains will move southeast late
tonight, potentially holding together long enough to move into the
Mid-South. These storms will weaken as they move into a less
favorable environment with weaker deep-layer shear and a good
amount of convective inhibition. Most of the instability will be
elevated at this time and could support a few thunderstorms toward
sunrise into Wednesday morning. This activity is forecast to pull
off to the east by midday.
The afternoon air mass will be pretty unstable with SBCAPE
forecast to exceed 3000 J/kg. However, we may be in a somewhat
subsident regime in the wake of the shortwave trough passing to
our north during the morning hours. This should limit, if not
preclude, convective initiation during the afternoon. While
confidence is low that diurnal storms will develop along the
residual outflow boundary from the morning convection, there is a
conditional threat for strong to severe storms. Thus, we will
include a slight chance of afternoon thunderstorms, mainly across
northwest TN and the MO Bootheel, given this conditional threat.
MJ
&&
.PREV DISCUSSION... /issued 331 PM CDT Tue May 17 2022/
DISCUSSION...
Relatively quiet weather expected over the Midsouth through
Friday, as daytime temperatures prevail above normal.
Midafternoon satellite and radar analysis showed a remnant MCV
lifting east across AR. This feature was encountering progressively
drier air while also gradually weakening. To the north, a well-
organized MCS east of Omaha was ongoing at discussion time. Post-
sunset, expect southward propagation component to develop over
MO. By 12Z Wednesday, the remnant MCV is progged by the 18Z HRRR
to lift into central IL, while storms over southern MO and
southern IL become outflow-dominate and weaken. Chance PoPs will
be maintained over northern portions of the Midsouth Wednesday
morning, and could see storms reintensify a bit with daytime
heating before crossing the TN River late in the morning. Otherwise,
low amplitude ridging aloft and returning southwesterly low level
flow will result in daytime highs around 10 degrees above normal
Wednesday afternoon.
A near repeat expected Wednesday night, with storms lifting east
through the Ohio River valley, perhaps skirting far northeast AR,
the MO bootheel and far northwest TN Thursday morning.
Upper level flow will transition to southwesterly by Thursday
night, in advance of a broad, progressive longwave trof over the
Rockies. Airmass should remain capped to deep convection by an
elevated mixed layer Friday afternoon. This EML will erode Friday
night, concurrent with midlevel height falls and strengthening
low level moisture advection.
Today`s 12Z medium range models showed relatively tight consensus
with respect to cold frontal passage and thunderstorm timing -
depicting frontal passage through east AR into northwest TN
during the afternoon and early evening, and north MS through late
Saturday evening. This timing would provide access to diurnally-
maximized mixed-layer CAPE, which the GFS and ECMWF suggests could
be as high as 2000 J/kg. Absent a frontal wave, low-level helicity
should be weak, given the tendency of pre-frontal winds to veer
during the day. Midlevel lapse rates will favor some large hail in
any pre-frontal discrete cells that develop Saturday afternoon.
Otherwise the main threat appears to be damaging winds and flash
flooding.
Saturday`s cold front should stall over south MS Sunday, before
returning north Monday. Latest guidance keeps subtropical
moisture in place over northeast MS, reflected in continuing low
end rain chances Sunday and Monday.
Deterministic GFS appears overdone with the intensity of an
approaching shortwave next Tuesday, and is out of agreement with
the GFS ensemble mean and the ECMWF. Most likely scenario early
next week: warm and more humid with thunderstorm chances favoring
the heat of the day.
PWB
&&
.AVIATION...
/00z TAFs/
VFR conditions will continue through the period. A disturbance
will push through north Tennessee, and possibly affect JBR, so
have added vcsh. South/southwest winds will start at 5 to 10 kts
tomorrow morning then eventually increase and gust up to 20 kts by
the afternoon.
SWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
Area Forecast Discussion
National Weather Service Norman OK
632 PM CDT Tue May 17 2022
...New AVIATION...
.SHORT TERM...
(This evening through Wednesday)
Issued at 212 PM CDT Tue May 17 2022
Instability is increasing again as the clouds associated with this
morning`s convection moves out and dissipates. A number of the
models have been showing precipitation developing in the west near
or ahead of the dryline and added POPs this morning for this
afternoon and this evening, and have expanded the POPs in time
through 06Z based on the current model trends. Any storms that do
develop are expected to be widely scattered given that there is
still a bit of convective inhibition, so currently do not think
that POPs higher than 20 percent are needed. Although the dryline
itself looks to remain farther west in the panhandles, surface
moisture will still mix out some in far western Oklahoma leading
to high temperature-dewpoint differences supporting an environment
where thunderstorms could produce strong downbursts. There will
be some hail potential as well given the expected instability. The
HRRR is explicitly forecasting some heatbursts with dissipating
convection late tonight. We did have some heatbursts overnight and
this morning, and the environmental set up would support
additional heatbursts this evening if convection does develop.
Another very warm day is expected tomorrow with triple digit
temperatures expected in the southwest. A surface front will
slide into at least the northwestern part of the area tomorrow
taking a little of the edge of the forecast temperatures northwest
of the boundary. With the hot temperatures and low dewpoints in
the southwest, minimum humidity values will fall to 10-15 percent
in the southwest elevating fire weather concerns, but fortunately
the winds will not be too strong as the surface pressure gradient
relaxes near the front.
&&
.LONG TERM...
(Wednesday night through next Monday)
Issued at 421 PM CDT Tue May 17 2022
A fairly unstable upper-air pattern is expected to continue
Wednesday night through Friday, where a zonal flow with frequent
perturbations and shortwaves. Across southeastern Colorado
through the Texas panhandle, another round of storms will likely
develop along a boundary, however they are anticipated to
dissipated before making it into western Oklahoma and north Texas.
A more established troughing pattern arrives in the northern US
Friday morning, with an upper level cyclone moving through North
Dakota/Minnesota on Friday. A cold front extending from the
associated surface low will begin moving through the region Friday
night through Saturday, bringing much cooler, below average
temperatures on Saturday. Precipitation chances increase through
Friday night into Saturday, mainly along and east of I-35.
Large differences continue within the long range models/ensembles on
the upper air pattern early next week, in particular the development
of a trough across the southwestern US and the possibility of a
trough moving through the region, bringing widespread precipitation
chances. For now, low precip chances have been included, but trends
be monitored through the weekend.
Zwink
&&
.AVIATION...
(00Z TAFS)
Issued at 630 PM CDT Tue May 17 2022
VFR will apply through the forecast. A few storms may try to move
into western OK from the TX panhandle, but confidence is not high
enough to include a mention at WWR or CSM. Mid to high clouds
will increase, however, over most terminals tonight. Wind speeds
will decrease overnight and then a shift from the north and
northeast is expected Wed afternoon and evening.
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 73 95 67 95 / 20 0 10 0
Hobart OK 71 99 66 102 / 20 0 0 0
Wichita Falls TX 75 106 69 105 / 10 0 10 0
Gage OK 60 91 60 99 / 20 0 10 0
Ponca City OK 68 90 64 93 / 20 0 10 0
Durant OK 70 95 71 94 / 10 0 10 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&
$$
SHORT TERM...26
LONG TERM....50
AVIATION...03