Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/16/22
Area Forecast Discussion...UPDATED
National Weather Service Amarillo TX
644 PM CDT Thu Sep 15 2022
...New AVIATION...
.SHORT TERM ...
(This evening through Friday night)
Issued at 241 PM CDT Thu Sep 15 2022
Upper level S/WV trough axis is currently position across the
WRN half of the Panhandles. Expect enough moisture and
instability for this disturbance to generate ISO to SCT storms
this aftn/eve. 18 UTC RAP analysis indicated around 500 J/kg
MLCAPE with around 25-75 J/kg CIN, but the CIN was wiped out in
the 19 UTC analysis while MLCAPE increased to 500-1000 J/kg. We
have certainly seen CU field develop in the past hour or so and
there are even some isolated showers now as well, so convective
initiation has begun. Wind shear will be a limiting factor
initially, but effective bulk shear is shown to increase to 30-40
kts around 00 UTC which certainly supports the marginal SVR risk
per SPC. The potential for svr storms could have been greater, but
timing of the strongest lift, best shear and highest MLCAPE are
not in perfect alignment mainly due to the location/timing of the
S/WV already over the area. S/WV timing/location is the main
reason that the highest POPs (30-40 percent) favor the east this
aftn. Severe wind gusts will be the greatest threat from storms
today, but there could be localized severe hail slightly greater
than 1 inch as well.
There is a little more cap in place on Friday, but the modest H7
theta-e ridge remaining over the area suggests a final very weak
s/wv in the aftn could generate a storm or two in the east where
forecast soundings show a period with weak SFC convergence, no cap
and 500-1000 J/kg SBCAPE. Based on this, went above NBM POPs and
included a mention of TSTMs for areas w/ 10-20 POP just east of
AMA. Can`t rule out a severe storm given the combination of wind
shear and CAPE, but things would have to really come together for
that to occur and percentages remain low. Highs will reach the
90s most locations and this will be the first of several days of
this to come as things heat up.
Gittinger
&&
.LONG TERM ...
(Saturday through next Wednesday)
Issued at 241 PM CDT Thu Sep 15 2022
Temps nearing triple digit territory again for the early part of
the week. Dry until mid to late week when a front comes through.
By Saturday there will be general troughing in the west with the
axis over California and ridging in the east with the axis over
the Ohio Valley. This will place the Panhandles in southwest flow
aloft. The trough looks to dig through Sunday down the western
coastline. This will allow for a closed high pressure dome to set
up over the Ark-La-Tex region for the early part of the week. Long
range models continue to bounce around the low around the
California coast and the high pressure dome around Texas. As
shortwaves ride around the ridge, the flow will likely take storms
that form off the mountains northeastward into CO and KS. By
midweek though, models indicate a front could enter the
Panhandles. The frontal passage looks to bring precip chances with
it. Models disagree on the timing of the passage through, which
leaves the NBM with various low end precip chances from Wednesday
afternoon through the end of the week. Will need to monitor trends
for any consistency between models and runs to get a better sense
of the frontal timing.
Beat
&&
.AVIATION...
(00Z TAFS)
Issued at 634 PM CDT Thu Sep 15 2022
A thunderstorm will still be possible at AMA early this evening,
so have a TEMPO group in there. Otherwise, thunderstorms should
stay to the east of the TAF sites for this forecast. Southerly
winds will turn more to the west before sunrise at DHT and GUY,
but then they will turn back out of the south and southwest in the
afternoon. Southerly winds will continue at AMA and they will get
gusty again by late morning. Skies are expected to remain VFR
outside of the thunderstorms.
&&
.PRELIMINARY POINT TEMPS/POPS...
Amarillo TX 63 91 66 93 / 20 10 10 0
Beaver OK 63 94 68 96 / 50 10 10 10
Boise City OK 54 90 59 91 / 10 0 10 0
Borger TX 67 95 70 97 / 20 10 10 0
Boys Ranch TX 63 92 66 94 / 10 10 10 0
Canyon TX 63 91 64 93 / 10 10 10 0
Clarendon TX 63 91 67 93 / 20 10 10 0
Dalhart TX 57 90 60 92 / 0 0 0 0
Guymon OK 61 94 65 96 / 20 10 0 10
Hereford TX 62 92 64 94 / 10 10 10 0
Lipscomb TX 65 94 68 96 / 40 10 10 10
Pampa TX 64 91 67 93 / 20 20 10 0
Shamrock TX 63 94 67 95 / 20 10 10 0
Wellington TX 64 94 68 96 / 10 0 0 0
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...None.
OK...None.
&&
$$
SHORT TERM...88
LONG TERM....16
AVIATION...15
Area Forecast Discussion
National Weather Service Burlington VT
942 PM EDT Thu Sep 15 2022
.SYNOPSIS...
A cold night is on tap for the North Country with lows expected to
drop into the mid 30s to mid 40s. Some patchy frost will be possible
across the Adirondacks and Northeast Kingdom given the cooler
temperatures and light winds. Friday will be a rinse and repeat of
today but a degree or two warmer across the region. Dry weather
continues through much of Saturday before rain chances increase
Saturday night.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
As of 938 PM EDT Thursday...Forecast is on track, with clear
skies currently but mid and high clouds approaching from the
northwest/Canada. Made some minor updates to temperatures, dew
points, and winds/wind gusts to keep up with the latest obs, but
it`s still dry, slightly breezy, and chilly out there across
the forecast area. Previous discussion below:
Previous Discussion...We should continue to see some light
winds through the overnight period with a well mixed boundary
layer. The HRRR vertically integrated smoke shows a plume of
elevated smoke (like 20,000 ft high) nosing into the North
Country around 7 PM. Be rest assured, no smoke will be anywhere
near the surface so we don`t anticipate any air quality issues.
Temperatures will fall quickly through the first part of the evening
with clear skies and mostly light winds in place. A deck of high
clouds will move into the region and should help moderate
temperatures a bit from truly bottoming out. Still, it should be
quite the chilly night with lows in the mid 30s to mid 40s. Patchy
frost is expected across the Adirondacks and Northeast Kingdom but
should patchy enough and only around for a brief period to not
warrant a frost advisory tonight. Another fall-like day is on tap
for Friday with highs once again in the 60s but only in the mid 40s
at the higher elevations. Mostly clear skies with a few high clouds
will be on tap so be sure to enjoy the great outdoors if you`re able
to.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 300 PM EDT Thursday...Saturday continues to look like the
better of the 2 weekend days as high pressure centered over the
Northeast in the morning slowly drifts off the eastern seaboard by
the afternoon/evening. Increasing southerly flow on the backside of
the high will push a warm front northward through the region during
the morning hours with perhaps a few sprinkles around, but drier and
warmer conditions will develop for the afternoon in the warm sector
as the front moves north of the Canadian border. Highs will be
seasonal ranging from the upper 60s to mid 70s.
More unsettled weather is then expected for the remainder of the
weekend as model consensus shows the aforementioned warm front
stalling just north of the Canadian border with several weak pieces
of shortwave energy passing through the forecast area. This energy
combined with an increase in low/mid level moisture marked by PWATs
rising to around 1.5" give or take a quarter inch, will support
scattered to numerous showers developing Saturday night through
Sunday, mainly across central/northern zones closer to the frontal
boundary. After a few cool nights, Saturday night will be much
milder with increased clouds and precipitation around. Look for lows
only in the mid 50s east to mid 60s west. Highs Sunday will be
variable based on where precipitation sets up, with current thinking
being upper 60s to mid 70s across the mid/northern zones and mid 70s
to around 80 south.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 300 PM EDT Thursday...Heading into next week the focus remains
on the aforementioned frontal boundary which looks to interact with
a potent northern stream shortwave trough dropping southeast from
Ontario Monday afternoon and evening. After a brief lull Monday
morning, this interaction will bring more widespread showers to the
region Monday afternoon into Tuesday morning until the trough shifts
east Tuesday afternoon when a brief ridge of high pressure builds in
for Tuesday night. Thereafter, guidance diverges on the timing of
our next strong frontal boundary which when it comes through will
bring a period of showers, potentially heavy, followed by the
coldest air of the early fall season. The GFS is the most
progressive with this feature with fropa occurring Wednesday night,
while the ECMWF isn`t until Thursday afternoon, and the GDPS is even
more delayed until Friday. Will offer chance PoPs for now given this
uncertainty.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Through 00Z Saturday...Very quiet aviation weather expected over
the next 24 hours as high pressure builds in. Seeing a thin
layer of smoke from western US fires high up in the atmosphere
on satellite, but this will stay well above 10kft. Otherwise, a
mid-level cloud deck will spread over our area overnight into
Friday, but widespread VFR conditions are expected to continue.
Winds overnight will be from the northwest generally between 5
and 15 knots through the TAF period, with some occasional
afternoon gusts to 20 knots possible.
Outlook...
Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
Saturday Night: VFR. Chance SHRA.
Sunday: Mainly VFR, with local MVFR possible. Chance SHRA.
Sunday Night: MVFR/IFR conditions possible. Chance SHRA.
Monday: Mainly IFR, with local MVFR possible. Likely SHRA.
Monday Night: IFR. Chance SHRA.
Tuesday: Mainly IFR, with areas MVFR possible. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Clay
NEAR TERM...Clay/Storm
SHORT TERM...Lahiff
LONG TERM...Lahiff
AVIATION...Duell
Area Forecast Discussion
National Weather Service Cheyenne WY
531 PM MDT Thu Sep 15 2022
.SHORT TERM...(This evening through Friday night)
Issued at 230 PM MDT Thu Sep 15 2022
Scattered showers and thunderstorms have begun developing early
this afternoon over southeast WY. An uncapped region of 500 J/kg
MLCAPE off the latest RAP has developed along and east of the
South Laramie Range ahead of a shortwave passage expected today.
This area of instability looks to expand this afternoon leading to
increasing storm coverage, especially within the area from
Cheyenne to Alliance and south towards Sidney. Latest GOES WV
imagery shows the shortwave over south-central WY that will
continue to propagate northeast throughout the day.
While severe thunderstorms are not expected this afternoon and
evening with shear values maxing out around 20 kt, occasional
lightning, brief periods of heavy rainfall, and gusty winds will
be the main hazards. QPF amounts will mostly be around 0.25" with
storms, but WoFS guidance has hinted at 0.50" possible, especially
within the areas mentioned above. As for gusty winds, drier
boundary layers are present, but would not consider this an
inverted-V sounding. Latest radar imagery has shown a few outflow
boundaries form north of Cheyenne from these initial storms with
gusts up to 32 mph being reported at the Whitaker WYDOT station.
As this afternoon goes on, stronger storms should be able to
produce stronger outflow boundaries with gusts to 40-45 mph
possible. Latest WoFS guidance shows 90th percentile max 10m gust
around 35-40 kt across much of the southern NE Panhandle through
00z. Most hi-res guidance shows storms dissipating and exiting the
eastern boundary of the CWA by 11 PM MDT.
Another round of storms will be possible Friday with another
shortwave passage under this active pattern. Increasing
convergence along a developing lee side trough should aid in storm
development along with better instability profiles. Upper level
flow increasing from 15 kts at 500mb with Thursday`s shortwave to
35 kt will elevate shear parameters across the region. Fairly uni-
directional shear with weak boundary layer winds should assist
with vertical momentum transfer of stronger winds near the
surface. Main hazards look to be strong outflow winds, but cannot
rule out small hail. SPC Day 2 Outlook does have a Slight Risk
over much of the NE Panhandle mainly for the wind threat. In
addition to the storms, cooler weather will continue for areas
along and west of the Laramie Range in the 60s and points east in
the 70s up to 80 in spots.
.LONG TERM...(Saturday through Thursday)
Issued at 230 PM MDT Thu Sep 15 2022
Long Range models continue to be in good agreement this weekend
and early next week. All models show the upper level ridge axis
rebuilding over the Front Range and adjacent Great Plains states
late this weekend. For Saturday, Still a good chance for showers
and thunderstorms Saturday afternoon, but coverage should be a
little lower compared to Friday. Models have trended a little more
favorable for widespread convection Saturday afternoon with
moderate southwest flow aloft and decent instability. Models now
show a weak shortwave moving northeast across southeast Wyoming in
the afternoon which will likely enhance convection into the
evening. High temperatures should be a little warmer compared to
Friday and generally in the 70s across southeast Wyoming with low
80s across western Nebraska. Another drying trend is expected
Sunday and Monday with highs climbing back into the upper 70s to
upper 80s for southeast Wyoming and into the low to mid 90s for
western Nebraska. Other than fire weather concerns and gusty winds
between 30-40 MPH each afternoon, not much weather related
impacts expected.
As we head into the middle of next week, there is the potential
for a wet pattern to set up across most of southeast Wyoming and
western Nebraska, but models are not locking in on the specifics
too well as we approach Thursday. All models and even most of the
ensembles suggest that a tropical system near the Mexico coastline
will lift north ahead of the next approaching Pacific upper level
trough. Deep moisture looks to transport northward as the
westerlies take over ahead of the approaching Pacific system. In
addition, the ECMWF and Canadian models show the upper level
trough stalling while slowly drifting northeast towards Montana
for Thursday and possibly next Friday, which may result in a
prolonged moderate to heavy rain event. The GFS is more
progressive, showing the trough rapidly ejecting northeast towards
the Canadian border. Thankfully, not much cold air is associated
with this upper level trough with snowlevels above 9500 feet,
which is considerably warmer than yesterday. However, we`ll see if
this changes as we approach the weekend. Kept POP between 40 to
60 percent since we`re still 6 to 7 days out, but if current models
verify, expected rainfall may make quite a dent in the current
drought across the state. High and low temperatures during this
period will be highly depended on the quantity of clouds and
rainfall across the area. Therefore, forecast temperatures
Wednesday through Friday may be subject to high variability
depending on model trends over the next several days.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 522 PM MDT Thu Sep 15 2022
Wyoming TAFS...VFR. Thunderstorms in the vicinity until 03Z. Wind
gusts to 20 knots at Rawlins and Cheyenne until 02Z, then to
30 knots at all terminals after 15Z Friday.
Nebraska TAFS...VFR. Occasional thunderstorms producing wind gusts
to 35 knots at Alliance and Sidney until 03Z. Thunderstorms in the
vicinity at Scottsbluff until 04Z. Wind gusts to 25 knots at
Sidney until 03Z, then gusts to 20 knots at all terminals after
15Z Friday.
&&
.FIRE WEATHER...
Issued at 230 PM MDT Thu Sep 15 2022
Minimal fire weather concerns the next few days with daily
chances for showers and thunderstorms continuing through Saturday.
Temperatures will begin to warm back up Sunday and Monday leading
to elevated fire weather conditions. The return of above average
temperatures will help drive afternoon RHs into the teens for much
of the area. Monday will be the main day to watch as winds west
of the Laramie Range will approach critical thresholds. Cool and
wetter weather pattern looks to return middle of next week.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...MB
LONG TERM...TJT
AVIATION...RUBIN
FIRE WEATHER...MB
Area Forecast Discussion
National Weather Service El Paso Tx/Santa Teresa NM
521 PM MDT Thu Sep 15 2022
...New AVIATION...
.SYNOPSIS...
Issued at 100 PM MDT Thu Sep 15 2022
Quiet and drier weather has moved into the region. This pattern
will give us mostly clear skies with high temperatures moving
around 5 degrees above average for Friday through the weekend. The
moisture and rain chances will try to return to the region for
the start of next week, along with some slightly cooler high
temperatures.
&&
.SHORT TERM...
(This afternoon through Friday)
Issued at 100 PM MDT Thu Sep 15 2022
Current satellite imagery shows our recent disturbance over the
Northern Great Plains and Upper Midwest, about to bring some heavy
rains to northern Minnesota and southwest Ontario. Closer to home
across the Borderland region, southwesterly flow continues to advect
in dry air across the region. In fact, this morning`s EPZ sounding
continued the trend in drying with a PW value of 0.9 inches and
decent mid to upper level dry layer. That being said, low level
moisture is still present across the area will dew point
temperatures in the upper 50s. Latest visible satellite imagery
confirms the presence of low level moisture with a growing cumulus
field predominately along and over the mountains chains of southern
NM and far west TX. With the dry air aloft, further cloud growth
will be limited with updrafts failing to ascend through the dry
layer. RAP and other high-res model guidance shows minimal amount of
CAPE over the area (mainly east) with CAMs hinting at a very slim
chance of seeing an isolated shower or storm over Otero or Hudspeth
County. SREF prob guidance shows eastern Hudspeth/Otero Counties
have a 20-40% probability of seeing 0.01 inches of rain this
afternoon and evening, those numbers don`t offer a lot of
confidence. With that being said, went ahead and left 10% PoPs in
the grids for isolated areas in eastern Hudspeth/Otero Counties.
Temperatures this afternoon across the desert lowlands will top out
around 90 degrees. For tomorrow quiet and dry weather conditions can
be expected with temperatures in the lower 90s across the desert
lowlands.
&&
.LONG TERM...
(Friday night through next Wednesday)
Issued at 100 PM MDT Thu Sep 15 2022
As the long term forecast picks up we will see an upper level
ridge strengthening to our east and an upper level trough
strengthening to our west. Initially all this will do for us is
change our upper level flow from the west to the southwest on
Saturday. This pattern will continue our mostly clear and dry
weather on Saturday. On Sunday, both the upper level ridge and
upper level trough will continue to strengthen and that will
continue to turn our upper level flow from the southwest to the
south. This will begin to draw moisture up from northern Mexico.
Sunday will still be mostly dry and warm, but by Sunday night we
will see enough moisture to see some rain chances mainly west of
the Rio Grande. There are still some differences in the extended
range. The ECMWF model continues to strengthen the upper level
ridge to our east on Monday and Tuesday and this begins to push
the moisture tap back into Arizona. The GFS is somewhat trending
in that direction. I went ahead and left some rain chances in the
extended forecast for most of the area, to avoid flip flopping
back and forth, but if later model runs keep the drier solution
going forward, we will likely have to reduce or even pull rain
chances for the start and middle of next week.
Looking at high temperatures, now that the moisture has cleared
out of the region and we will begin to feel more of the effects of
the upper level ridge, we will see our high temperatures trending
higher. High temperatures on Saturday and Sunday will run three
to five degrees above average. The high temperatures for the first
of next week, will depend on how much moisture and clouds get in
to the area. For now I have trended the high temperatures down a
few degrees, but they are still running two to four degrees above
average, maybe closer to seasonal averages for locations near the
NM/AZ border.
&&
.AVIATION...
(00Z TAFS)
Issued at 520 PM MDT Thu Sep 15 2022
VFR conditions expected through the forecast period. FEW-SCT
cumulus may linger into this evening outside of KDMN. SKC
otherwise, although FEW CU around 080 could develop tomorrow
afternoon. Winds AOB 12kts generally from SW.
&&
.FIRE WEATHER...
Issued at 100 PM MDT Thu Sep 15 2022
Zonal flow and drier air can be expected through the first half of
the period (through the weekend) with LOW fire weather concerns. Min
RHs will decrease each day through Saturday with 15-30% values
areawide. Winds will become low-end breezy each afternoon/evening
over the mountains due to increased southwest flow and terrain
effects. The increase in the HDWI aforementioned in yesterday`s fire
weather discussion continues to show a decent increase for tomorrow
and Saturday over mountain zones, with a probability of 90th
percentile exceedance of 20-40% on Saturday.
That being said, ground fuels and vegetation remain quite saturated
with Energy Release Component (ERC) values at or below the average
for the middle of September. Temperatures will continue to increase
each day with high in the low 90s across the desert lowlands and
temps slight above or right around average for mountain zones.
- Again, fire weather conditions/concerns are LOW through the
weekend due to very saturated vegetation and fuels.
Increased moisture and rain chances can be expected at the beginning
of next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 68 94 69 95 / 0 0 0 0
Sierra Blanca 63 87 63 87 / 0 0 0 0
Las Cruces 61 92 63 93 / 0 0 0 0
Alamogordo 63 90 65 92 / 0 0 0 0
Cloudcroft 47 67 49 69 / 0 10 0 0
Truth or Consequences 59 90 60 91 / 0 0 0 0
Silver City 57 82 58 82 / 0 0 0 0
Deming 58 92 59 93 / 0 0 0 0
Lordsburg 61 89 61 90 / 0 0 0 0
West El Paso Metro 67 93 69 94 / 0 0 0 0
Dell City 63 92 64 93 / 0 0 0 0
Fort Hancock 65 93 65 94 / 0 0 0 0
Loma Linda 62 85 63 86 / 0 0 0 0
Fabens 66 93 66 95 / 0 0 0 0
Santa Teresa 63 91 65 93 / 0 0 0 0
White Sands HQ 65 91 66 92 / 0 0 0 0
Jornada Range 63 89 64 90 / 0 0 0 0
Hatch 60 91 61 93 / 0 0 0 0
Columbus 62 90 62 92 / 0 0 0 0
Orogrande 62 90 64 92 / 0 0 0 0
Mayhill 53 79 54 80 / 10 10 0 10
Mescalero 52 77 54 79 / 0 10 10 10
Timberon 51 77 53 78 / 0 10 0 0
Winston 53 82 52 83 / 0 0 0 0
Hillsboro 58 87 58 89 / 0 0 0 0
Spaceport 60 89 61 90 / 0 0 0 0
Lake Roberts 51 80 52 81 / 0 0 0 0
Hurley 58 88 58 89 / 0 0 0 0
Cliff 53 89 53 90 / 0 0 0 0
Mule Creek 56 82 55 84 / 0 0 0 0
Faywood 59 86 59 87 / 0 0 0 0
Animas 59 90 59 91 / 0 0 0 0
Hachita 59 90 59 90 / 0 0 0 0
Antelope Wells 58 88 59 91 / 0 0 0 0
Cloverdale 58 83 58 85 / 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
TX...None.
NM...None.
&&
$$
SHORT TERM...38
LONG TERM....15
AVIATION...39-Aronson
Area Forecast Discussion
National Weather Service Grand Forks ND
1002 PM CDT Thu Sep 15 2022
.UPDATE...
Issued at 959 PM CDT Thu Sep 15 2022
Low pressure is in northeastern SD west of Sissteon. Frontal
boundary is pretty much stalled northeast from the low to north of
Wahpeton to Barnesville to Mahnomen to Bemidji. Activity tried to
get going some in far SE ND near the front and low but has
dissipated. T-storms have formed and continue in a zone from east
of Thief River Falls to north of Bemidji and this is in a zone of
850 mb warm advection per SPC meso analysis. This band will likely
continue a few more hours before shifting more east. Farther west
rain showers continued west toward Grafton and Devils Lake. They
are slowly drifting northeast. Latest guidance shows sfc low ever
so slowly moving northeast toward Bemidji by Friday aftn. Showers
will be more likely in north central and northwestern MN and far
northern RRV and into S Manitoba as we head into daytime Friday.
Adjusted pops, winds and temps a bit for current conditions.
UPDATE Issued at 707 PM CDT Thu Sep 15 2022
Cold front only slowly slipping south this early evening. It runs
from Bemidji to Lake Park MN to in between Fargo and Wahpeton to
Forman ND. T-storms tried to get going south of the front in the
warm sector in far SE ND and WC MN, but bulk shear is blo 20 kts
and despite 2000 j/kg sfc cape not much is able to get going. So
what is left is an area of light rain showers from Devils Lake
through Grand Forks/Grafton area to Baudette. Rain amounts from
these are light and no thunder. So update was done to remove
thunder from the north but keep it in far SE ND into MN. NBM pops
were too high with 90s as coverage is scattered (even isolated)
all but band from DVL to BDE. Not expecting much change overnight
as light rain showers will continue around the area with the more
persistent rain shower area likely to diminish or shift more into
N MN overnight. Rain amounts light though.
&&
.SHORT TERM...(This evening through Friday night)
Issued at 226 PM CDT Thu Sep 15 2022
We continue to see isolated showers and storms across the area this
afternoon and this looks to continue throughout the rest of today
and into tomorrow. A frontal boundary is draped across the forecast
area helping to ignite these showers and isolated storms. Guidance
continues to show through HREF and HRRR showers and storm
development throughout the evening hours along this frontal
boundary. Moisture through the 850mb level continues to push into
the region helping to bring high PWAT values. Instability is rather
weak around 500 J/kg and shear is <25kts. We don`t expect any severe
thunderstorm development, but a stray stronger storm at times can`t
be ruled out especially along and east of the front.
Areas in NW MN and into northern MN could see some locally heavy
rainfall at times, as atmospheric soundings in those region have
saturation through the upper levels and higher instability. Flash
flooding is not a concern as the ground has been dry for several
months and should be able to absorb additional rainfall. QPF totals
through today and into the early portion of the weekend will vary
across the forecast area. Areas toward Lake of the Woods and
Beltrami could see up to 2 inches which is a 30-40% chance of
occuring, whiles areas into the valley have a chance of 40-50% of
seeing up to 0.75 inches. These rain chances will be isolated to
scattered and not widespread. Temperatures are expected to be on the
cooler side behind the front, with lows tonight dropping to the
upper 40s near the Cando and Langdon area and lower 60s ahead of the
front in Ottertail county. Continued rain will help keep
temperatures cooler tomorrow, with highs only in the 50s in NE ND
and the low to mid 60s in west central and NW MN. Impacts are
possible from any stronger storms that develop or locally heavy
rainfall in NW and northern MN.
.LONG TERM...(Saturday through Thursday)
Issued at 226 PM CDT Thu Sep 15 2022
Saturday through Thursday: The models and cluster analysis show an
upper low digging into the western seaboard throwing our region into
an upper ridging pattern for the early half of next week. There are
some transient shortwaves to accompany this weather pattern. This
may lead to an increase in instability ahead of the next wave that
is progged to travel through the upper flow pattern late Monday into
Tuesday. There is significant disagreement on the location and
timing of this wave within ensemble guidance at this time, however,
leading to lower confidence in precipitation potential. The 850mb
dewpoints suggest sufficient moisture between 8-12C over our area
Sunday through Tuesday. Some light rain showers are possible within
this time period. NBM has a 20-30% of showers (not exceeding 0.25
inches) for the Red River Valley and NW Minnesota area Monday and
Tuesday. Wednesday looks to be the end of the rainy pattern as we
enter a dry northerly flow. The high temperatures are expected to be
in the high 60`s over the weekend but temperatures will warm back up
into the 70`s starting Monday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 707 PM CDT Thu Sep 15 2022
IFR ceilings anticipated to continue through Friday northeastern
ND and far NW Minnesota. IFR cigs (or low end MVFR) will push
south into Fargo and Bemidji overnight as cooler air spreads
south. Winds north-northeast 8 to 15 kts. Wahpeton-Wadena zone
south wind to 20 kts before turning light/variable overnight.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Riddle
SHORT TERM...Spender
LONG TERM...Spender/MM
AVIATION...Riddle
Area Forecast Discussion
National Weather Service North Platte NE
727 PM CDT Thu Sep 15 2022
.SHORT TERM...(This evening through Friday night)
Issued at 417 PM CDT Thu Sep 15 2022
The main forecast challenges heading into the weekend revolve around
thunderstorm chances. With an upper level trough digging into the
Western US and some surface boundaries passing through the forecast
area, precip/thunder chances increase over the next couple days.
This evening and tonight... Nebraska lies in quasi-zonal or broadly
southwest flow aloft with the upper trough axis near the Pacific
Coast. Near the surface, a cool front bisects the forecast area,
generally stretching from KANW to KIML as of 20z. The front slowly
pushes east through the rest of the evening and overnight, along
with an H7 wave. These features will be the foci for additional
thunderstorm development, as there has been ongoing activity over
far north central Nebraska for much of the day. Expect some growth
farther southwest and some additional development in the panhandle
in the post-frontal environment, but that should not be as dominant.
Ahead of the front, near the CWA borders with OAX and GID, some
instability and fairly steep mid-level lapse rates exist. Deep layer
shear is marginal at best, ranging from 10 to 25 kts across the
forecast area. A low level jet develops tonight across central and
eastern Nebraska, which aids in strengthening low level shear. The
bigger impact would likely be that flow getting mechanically mixed
to the surface in/near any thunderstorms. Besides the wind, brief
torrential rain is a concern due to seasonably high PWAT in place
and decent moisture advection, partly shown by dew points in the
lower 60s. Used a general blend of HRRR and HREF guidance for PoP
coverage and timing, which suggests more organized activity along
the eastern edge of the CWA and more scattered showers/storms that
gradually weaken across the west. Most precip should dissipate or
move out of the area by 12z. For min temps, made little change from
previous forecast as they agree with the 12z model suite and NBM
envelope. Values range from the upper 40s northwest to near 60s
central.
Friday and Friday night... The upper trough nudges east, while a
stout H7 wave approaches the Sandhills and a surface cool front
drops through the Dakotas. A lull in the activity is anticipated for
much of the morning and into the afternoon, but the atmosphere
recharges for the evening. Continued low level southeasterly flow
keeps the moisture component around with dew points around 60F. When
combined with highs in the lower to mid 80s and steeper mid-level
lapse rates around 7-8C, CAPE values will be modest. The convective
parameter that really stands out is deep layer shear, which improves
drastically compared to this evening`s setup. Hodographs indicate
some slight veering in the low levels, but an elongated and straight
signature in the mid/upper levels. The main shear vector is largely
parallel to the front along the state line but perpendicular to a
weak surface trough in the panhandle. Convective mode appears rather
complex right now, with cells or clusters favored near and shortly
after initiation and possibly larger clusters or a linear system
after dark. Somewhat significant discrepancies exist amongst the
solutions, but overall the environment favors an active late
afternoon (far west) through late evening (central Neb). The main
threats appear to be strong winds and heavy rain, although some
smaller hail will probably accompany the cells or clusters.
.LONG TERM...(Saturday through Thursday)
Issued at 417 PM CDT Thu Sep 15 2022
This weekend... Nebraska lies in a battle zone aloft between the
deepening West Coast trough and a building Southern Plains ridge,
and a surface cool front crosses the forecast area. The frontal
passage presents another chance of thunder, mainly Saturday evening
into early Sunday. Severe parameters are marginal for western Neb
with the better instability to the east. Despite the front,
temperatures remain near or above normal with highs generally in the
80s and lows in the 50s.
Monday and beyond... The upper ridge gains influence over the
central Plains, which enables a return to summer-like conditions.
Another round of highs in the 90s is likely Monday and Tuesday with
the help of fair skies and southerly winds. Humidity levels drop in
the west, but winds should remain light enough to preclude any
significant fire weather concern.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 725 PM CDT Thu Sep 15 2022
Isolated showers and thunderstorms will continue to impact portions
of north central Nebraska this evening. Storms will gradually
diminish after 06Z with overcast skies giving way to scattered skies
by mid-morning Friday. VFR conditions will then continue through
Friday afternoon before another round of thunderstorms arrives after
00Z Saturday.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Snively
LONG TERM...Snively
AVIATION...Kulik
Area Forecast Discussion
National Weather Service Topeka KS
916 PM CDT Thu Sep 15 2022
.UPDATE...
Issued at 916 PM CDT Thu Sep 15 2022
With the boundary layer continuing to cool across north central
KS, surface based instability will continue to diminish. RAP
forecast soundings still show some elevated instability around 500
MB. But deep layer shear remains very weak so just some general
thunderstorms are expected as the upper level shortwave passes
overhead tonight. Most of the latest 00Z CAM guidance shows the
convection weakening before it gets to far east, so areas east of
MHK may not even hear thunder.
&&
.DISCUSSION...
Issued at 227 PM CDT Thu Sep 15 2022
Key points:
* Small risk for severe thunderstorms early tonight in north-central Kansas
* Periodic shower and thunderstorm chances tonight through Sunday
* Record/near-record hot temperatures likely early next week
Recent water vapor imagery showing several weak waves from the
central Rockies into north Texas moving northeast over high pressure
centered over the southeast CONUS. A few areas of convection formed
over north-central Oklahoma in recent hours along the edge of
deeper moisture but have struggled to maintain themselves.
The mean upper trough axis looks to move across the local area late
tonight into midday Friday. Precipitable water levels push up to
near 1.5 inches tonight and linger in this range into the weekend.
The main convective activity tonight looks to be well west and
somewhat delayed in recent guidance. The chances for storms reaching
the western counties before sunset is diminishing with MLCAPE
falling off to a few hundred J/kg in this area. If a multicell line
in a faster scenario reaches the area, a few near-severe wind gusts
would be possible with downdraft CAPE value around 1000 J/kg. There
is still good consistency with the mean wave interacting with the
increasing moisture for at least isolated precipitation moving
across the area tonight into midday Friday. Decent clearing and
south winds from 10-15 knots would support another warm afternoon.
Attention Friday night into early Saturday focuses to the northwest
with another wave passing over surface low pressure in western
Nebraska. A convective cluster should form there and may build south
into a modest low-level jet as it pushes east. This could bring
precip to northern portions of the area late Friday night into early
Saturday. There are suggestions of an outflow boundary lingering
into the afternoon, and with MLCAPE in the 1000-2000 J/kg range and
modest shear, severe storms can`t be ruled out. Convection could
linger into early Sunday morning as the low-level jet returns.
The upper ridge remains on track to rebuild to the south/southeast
early next week with very warm temps resulting. ESAT data from the
NAEFS and ECMWF are quite similar with 850 mb temps reaching record
to near-record values. NBM is on track with highs and lows in record-
warm range Monday and Tuesday. An upper trough passing across the
northern Plains Wednesday may bring a cold front into the area for a
cooler Wednesday and Thursday, though consistency with this pattern
change has not been high.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday)
Issued at 548 PM CDT Thu Sep 15 2022
Most guidance keeps the instability west of the terminals, and a
lot of the CAMs are showing precip diminishing as it moves east
overnight. There could still be a few showers around through mid-
morning as the upper trough swings overhead. But confidence in
timing something at a terminal is to low to go with anything other
than the VCSH for now. CIGS and VSBY should remain VFR thanks to
relatively dry air in the lower atmosphere.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Wolters
DISCUSSION...65
AVIATION...Wolters