Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/09/22
See below for an aviation forecast discussion for the 00Z TAFs.
&&
.SHORT TERM...(This Evening through Monday Night)
Issued at 323 PM CDT Sun May 8 2022
Main challenge in the near term is precipitation chances tonight
into early Monday, then winds Monday. The region will remain
situated on the east side of a broad upper level west coast trough
throughout the period. A fairly decent shortwave will ride up the
trough and over the Northern Plains late tonight and Monday, with
just a quieter southwest flow then expected through Monday night. At
the surface, a low pressure system will track from Colorado to
central Nebraska/central South Dakota tonight, spreading
precipitation across much of the CWA, mainly after sunset and
through the overnight hours. Concern becomes the potential for
thunderstorms, possibly strong to severe, as a low CAPE/high shear
situation sets up. CAMs are in fairly good agreement with the
potential for convective development beginning around 03Z or so
across central South Dakota, but not as much in agreement with if
the convection holds together to affect the eastern CWA late tonight
into early Monday morning. Will see a 40-50 knot low level jet
develop over the east late tonight, and that may aid in keeping
convection going across the east, which is hinted at by the HRRR and
the HiResW-FV3. The other CAMs do not seem to agree and take the
precipitation northward into North Dakota on the west side of the
low. Will keep at least some low POPs in across the east for now,
with the highest POPs across the west. Next concern is winds on
Monday as we get on the back side of the low. A somewhat tight
pressure gradient and good mixing should allow for winds reaching
advisory criteria at times. Therefore, have issued a Wind Advisory
for the entire area from mid morning into Monday evening. High
pressure will then nose in from the west, with quiet conditions
expected Monday night.
Low temperatures tonight will range from the mid 40s across north
central South Dakota, to the mid 50s across northeastern South
Dakota and west central Minnesota. High temperatures on Monday will
range from the upper 50s across north central South Dakota, to the
mid 70s across west central Minnesota. Lows Monday night will range
from the upper 30s across north central South Dakota, to the upper
40s across west central Minnesota.
.LONG TERM...(Tuesday through Sunday)
Issued at 323 PM CDT Sun May 8 2022
The upper pattern starts dominated by an upper trough over the
western CONUS and a building ridge in the midwest/northeast. This
will enhance flow aloft before the ridge migrates far enough north
and west that we end up primarily under its influence, before the
trough to the west begins to migrate east. As it does so, it
weakens, and then pivots into the western Dakotas and northwards,
swinging two distinct shortwaves across the area for late in the week
and weekend. At this timescale, details about specific impacts these
features may have are unreliable, but it looks like mainly a west to
east surface trough that will outrun its upper level support late
Thursday/Friday and a secondary trough that will have limited
moisture with a second dry line/cold frontal passage.
In the interim, we have a weak surface/bubble high with some cooler
temperatures in place to start things off Wednesday, before the
eventual formation of a lee low that follows a progressing from the
4-corners to northeast Colorado and up into the western Dakotas.
This Tuesday/Wed/mid-day Thurs period looks mostly unfavorable for
surface based convection, though Wednesday there is a push of some
800-700mb warm advection associated with the building midwest ridge
that could generate elevated convection. Profiles support MUCAPE in
the 1-2000 J/kg range and strong mid-level flow thanks to the
tightening height gradient between the two upper features. After
that, 700mb temperatures increase up to 2 standard deviations above
climo, which will need to be accounted for with discussion on severe
weather potential moving forward, raising a level of uncertainty in
how far east convection will progress associated with Thursdays
system.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday Evening)
Issued at 645 PM CDT Sun May 8 2022
Terminals KABR,KATY,KPIR,KMBG
VFR conditions begin the TAF valid period and are forecast to end
the TAF valid period. Between ~06Z and ~18Z, sub-VFR cigs and/or
visbies are forecast. There are also showers and thunderstorms
forecast to impact all four terminals at some point during the TAF
valid period, as a low pressure system works northward through the
region. Behind this low, west-northwest winds are forecast to
increase to as much as 25 to 30 knots, with gusts potentially up
to 40 knots.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory from 10 AM CDT /9 AM MDT/ to 8 PM CDT /7 PM MDT/
Monday for SDZ003>011-015>023-033>037-045-048-051.
MN...Wind Advisory from 10 AM to 8 PM CDT Monday for MNZ039-046.
&&
$$
UPDATE...Dorn
SHORT TERM...Parkin
LONG TERM...Connelly
AVIATION...Dorn
Area Forecast Discussion
National Weather Service Gaylord MI
1138 PM EDT Sun May 8 2022
.UPDATE...
Issued at 1037 PM EDT Sun May 8 2022
Bulk of mid-level returns have been moving se-ward, into
central/southern lower MI. Will keep an eye on weaker returns in
the Ludington area.
A skinny n-s band of mid-level returns is also seen over the east
half of upper MI, nearing western Mack Co. This may have the
potential to produce some sprinkles in eastern upper MI (the RAP
in particular has been spitting out QPF from time to time in MQT`s
eastern areas).
Otherwise, more mid-high clouds than last night will keep temps
milder. Did still tweak inherited min temps down slightly.
UPDATE Issued at 839 PM EDT Sun May 8 2022
Persistent radar returns noted in w-central lower MI, in a zone of
increasing mid-level theta-e advection, and with a weak shortwave
shearing out as it lifts into lower MI. There is a ton of dry air
below this, but it has been overcome. Ludington reports light
rain out of an OVC110 deck, and with a 30f temp/dew point spread.
Better forcing will move ese-ward with time, skirting the
southern border of this forecast area. Am monitoring, but have not
introduced any precip yet.
&&
.NEAR TERM...(Through Tonight)
Issued at 253 PM EDT Sun May 8 2022
...Dry and warm conditions continue...
Strengthening ridge axis overhead along with stubborn high pressure
to our northeast will keep dry conditions going through tonight and
beyond. Cirrus clouds are moving in from the west, overtopping the
ridge axis. Afternoon highs will top out in the upper 60s west of I-
75 (thanks to a little downsloping), and low to mid 60`s on the east
side and north of the bridge. With such dry low levels and great
mixing up to at least 850mb we`ve seen dewpoints dropping into the
low 20`s for some areas. We`ll remain dry with elevated fire
concerns through the remainder of the afternoon and very early
evening, before humidity rises a bit around sundown.
Winds will have a slight uptick tonight as the gradient gets
squeezed between the high pressure northeast and the low moving
north into the Dakotas. For tonight`s low temps believe we stay
milder than previous nights thanks to stronger winds and mid-high
&&
.SHORT TERM...(Monday through Wednesday)
Issued at 253 PM EDT Sun May 8 2022
...High Fire Danger Monday; Continued Warming Temperatures...
High Impact Weather Potential...High fire danger Monday.
The upper level ridge continues to strengthen through the period.
However, models are trending that the ridge axis may shift just
barely to east of the region. This may eventually allow for moisture
from a trough tracking by to our northwest to make it into the
region (later Tuesday into Wednesday). Low confidence of this
actually occurring as the ridge should be hard to overcome so only
slight to low chances for a few rain showers at this point (can`t
rule out a rumble of thunder). Meanwhile, the primary focus is on
the expected high fire danger Monday across northern lower. Looking
at model soundings, there is still lots of dry air at mid and upper
levels to mix down to the surface which should once again lower
relative humidity values in the afternoon (20 to 25 percent across
northern lower). The surface pressure gradient really tightens up
leading to southeast winds of 15 to 20 mph sustained and gusts to 30
to 35 mph. It will be warmer as well with highs ranging from 70 to
77 across northern lower (highest on the west side due to
downsloping) and between 65 and 70 across much of eastern upper. Of
course it will be much cooler downwind of the Great Lakes where
there is on-shore flow (specifically the Lake Huron shoreline and
across southern Mackinac County). The combination of the low
relative humidity, gusty winds and warm temperatures leads us to a
fire weather watch for high fire danger. Temperatures Tuesday will
be even warmer with highs ranging from the 60s north to near 80
southwest then the balmy 70s to mid 80s Wednesday.
.LONG TERM...(Wednesday night through Sunday)
Issued at 253 PM EDT Sun May 8 2022
High Impact Weather Potential...
...Summerlike Warmth; Increased Rain Chances?...
High Impact Weather Potential...None at this time.
Strong ridging remains centered just off to our east with more
troughing to our northwest. The chances for the ridge to break down
leading to falling heights/moisture from the trough making it into
our neck of the woods are increasing in the long range. This may
take until Saturday night or Sunday. In the meantime, more summer
like temperatures through Saturday followed by temperatures closer
to average for Sunday as shower chances enter the picture.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1138 PM EDT Sun May 8 2022
VFR. LLWS Monday evening.
High pressure is finally shifting east of the area, and se-erly
low-level flow will increase in its wake. The incoming air will
remain on the dry side, at least thru Monday. Lots of cirrus and a
bit of mid clouds out there tonight, though that will thin out
for Monday.
Se winds will be gusty at times, especially on Monday. LLWS
develops Monday evening, with strong south winds just off the
surface.
&&
.MARINE...
Issued at 253 PM EDT Sun May 8 2022
Southeast winds ramp up tonight and especially Monday as the
pressure gradient gets squeezed over us. Widespread small craft
criteria are expected on all nearshore waters through Monday and
into Monday night. A few gale force wind gusts are possible
especially on northern Lake Huron. Winds become lighter through
midweek.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...FIRE WEATHER WATCH from 8 AM EDT Monday through Monday evening
for MIZ016>018-020>036-041-042-099.
LH...SMALL CRAFT ADVISORY from 11 AM Monday to 5 AM EDT Tuesday for
LHZ345>349.
LM...SMALL CRAFT ADVISORY from 11 AM Monday to 5 AM EDT Tuesday for
LMZ341-342.
SMALL CRAFT ADVISORY from 8 AM Monday to 5 AM EDT Tuesday for
LMZ323-344>346.
LS...SMALL CRAFT ADVISORY from 11 AM Monday to 2 AM EDT Tuesday for
LSZ321-322.
&&
$$
UPDATE...JZ
NEAR TERM...STJ
SHORT TERM...AJS
LONG TERM...AJS
AVIATION...JZ
MARINE...STJ
Area Forecast Discussion
National Weather Service El Paso TX/Santa Teresa NM
557 PM MDT Sun May 8 2022
.AVIATION...00Z TAF CYCLE
Wind and blowing dust will be the biggest aviation concern this
period. SW wind at 20-25G30-40KTS possible until the sun sets.
Blowing dust at KDMN has lowered visibility to 1-2SM at times.
There is a dust plume blowing directly over KELP. KBIS, just to
the north of KELP has gotten down to 4SM. All blowing dust issues
should dissipate shortly after dark. Winds will also begin to
slowly weaken after dark as the atmosphere decouples. Terminals
will continue to see10-15G20 through morning, with the exception
of KELP, which will stay gusty through morning due to mountain
wave activity. An AWW has been issued through 12Z. LLWS is
possible this evening once the winds start to subside. Wind picks
back up Monday, albeit a bit weaker than today:
230-26015-25G35KT.
&&
.PREV DISCUSSION...247 PM MDT Sun May 8 2022...
.SYNOPSIS...
Mostly dry, hot, and breezy to windy conditions can be expected
for the upcoming week across the Borderland. Fire weather danger
will remain critical through Tuesday, with very dry air and windy
conditions in place. An increase in moisture and a slight chance
of thunderstorms return to the forecast on Wednesday. Areas east
of the Rio Grande Valley will have a slight chance of seeing some
moisture. Otherwise, dry, hot, and breezy conditions will prevail
into next weekend.
&&
.DISCUSSION...
.SHORT TERM...Tonight and Tomorrow...
Windy, dry and warm conditions are expected to continue this
afternoon due to lee-cyclogenesis over the Front Range. The surface
trough associated to this system expands across New Mexico leading
to a tight pressure gradient. Thus, we are going to have windy
conditions through the early evening hours. Once the sun sets, winds
will start to slowly decrease. However, breezy to windy conditions
are expected to persist along the eastern slopes of area mountains,
the Black Range and the Sacramento Mountains. So, we have wind
advisories in effect through most areas until 9PM. The Black Range
and the Sacramento Mountains are the area of uncertainty overnight.
The 700 mb winds show speeds in the 50-55 kts range between the GFS
and the NAM, but the BL winds remain around 35-45 kts. The soundings
of these models in the Sacs indicate the presence of an inversion
with lighter winds, although breezy. Hi-res models including the
HRRR, RAP and GLAMP have sfc winds just at or slightly below
advisory criteria. So, I have decided to let the next shift choose
if an extension of the advisory for the mountains is necessary. The
breezy winds across the area will keep above normal morning lows
across the region.
On Monday, the lee-side low starts moving to the east-northeast,
while the upper trough to our west slowly descend across the West
Coast. Therefore, the surface gradient relaxes a bit, resulting in
lighter winds across the area. Multiple deterministic and ensemble
models show lighter winds. Winds will continue to be from the
southwest between 15 to 25 mph. The strongest winds will lead to
blowing dust in dust-prone areas near the International Border,
including Deming. Visibilities could be down to 2-3 miles near
Deming, otherwise visibility reductions should stay above 5 miles.
Afternoon highs will be very similar to today. This will still keep
critical fire weather conditions across most of southern New Mexico
and far west Texas.
&&
.LONG TERM...Tuesday through Saturday...
Stagnant upper level pattern will continue through most of the
long term period as a blocking area of low pressure parks itself
off the east coast. This will result in hot, windy, and mostly dry
conditions for southern New Mexico and far west Texas. The region
will remain under deep southwest flow, as a amplified ridge (to
the east) and trough (to the west) slowly progress eastward. The
forecast period picks up heading into Tuesday. The ridge to our
east will slowly move eastward, in response, 500mb heights will
gradually fall as the trough over the western CONUS continues to
amplify. A lee-side surface cyclone will develop over SE CO in
response to an increase in cyclonic flow. A somewhat packed
pressure gradient will result, with breezy winds expected during
the afternoon/evening hours on Tuesday. High temperatures will
once again be in the low to mid 90s across the lowlands.
On Wednesday, further amplification of the trough out west will
allow the upper level ridge over the Mississippi River Valley to
expand. The combination between the expansion of the upper level
ridge and strengthening of the associated surface high pressure
will result in a westward push and expansion of moisture.
Clockwise flow in the low levels around the high, will pull
moisture up from the Gulf of Mexico and advect it into west Texas.
That being said, the dry line could potentially push into the eastern
zones of the forecast area with a slight chance of thunderstorms
east of the Rio Grande. Even though the chances as of now are
pretty slim, it feels good to talk about moisture :). Global
ensembles and their respected deterministic outputs are hinting at
modest instability with CAPE values of ~500 J/kg east of the Rio
and LI`s below 0, along with DCAPE values greater than 1000 J/kg.
The modest convective parameters suggest a strong storm or two
could be possible across eastern zones. But then again, we are
still ~3 days out and its hard to pin-point where exactly the dry
line will set up, so forecast confidence remains low. The
remainder of the forecast period (into the weekend) looks dry,
hot, and breezy as guidance suggests the return of deep southwest
flow.
&&
.FIRE WEATHER...
Elevated to critical fire weather conditions continue through most
of the week. Very dry weather is expected to persist with minimum
relative humidity generally in the single digits. We will have some
moisture intrusions from the Gulf of Mexico, but not enough to make
a real dent to the daytime moisture content. At least overnight
recoveries improve during the second half of the week, especially in
areas east of the Rio Grande. Temperatures will remain from above to
well above normal which will contribute to the issue. The
combination of dry weather, gusty winds and warm temperatures keep
fuels very dry. The main factor deciding if we are issuing Red Flag
Warnings or not, is wind. Breezy to windy conditions this
afternoon/evening and tomorrow have warranted the issuance of said
product. Most likely, we don`t need a red flag on Tuesday as wind
speeds decrease quite a bit in intensity, although some isolated
areas may still meet criteria for short periods of time. Wednesday
and Thursday will be close too, but there is still some uncertainty
as to how strong the winds will be. There is also a chance for some
storms in areas east of the Rio Grande on Wednesday, but chances
remain quite low. By Friday the upper trough that has been stalling
in the West Coast finally moves east, which will relax the pressure
gradient at the surface resulting in lighter winds this weekend.
Therefore, fire weather conditions improve over the weekend, but it
is still going to be very dry.
Ventilation rates will be excellent through Thursday.
&&
&&
.PRELIMINARY POINT TEMPS/POPS...
El Paso 64 92 62 95 / 0 0 0 0
Sierra Blanca 60 88 59 90 / 0 0 0 0
Las Cruces 59 91 56 93 / 0 0 0 0
Alamogordo 57 89 56 92 / 0 0 0 0
Cloudcroft 40 68 45 69 / 0 0 0 0
Truth or Consequences 57 89 55 90 / 0 0 0 0
Silver City 52 79 52 82 / 0 0 0 0
Deming 54 90 50 92 / 0 0 0 0
Lordsburg 52 87 50 90 / 0 0 0 0
West El Paso Metro 63 91 61 94 / 0 0 0 0
Dell City 57 91 53 94 / 0 0 0 0
Fort Hancock 57 95 57 98 / 0 0 0 0
Loma Linda 58 84 58 88 / 0 0 0 0
Fabens 59 94 58 96 / 0 0 0 0
Santa Teresa 57 90 55 92 / 0 0 0 0
White Sands HQ 64 89 62 91 / 0 0 0 0
Jornada Range 53 87 55 90 / 0 0 0 0
Hatch 59 89 54 91 / 0 0 0 0
Columbus 57 89 55 93 / 0 0 0 0
Orogrande 60 89 58 92 / 0 0 0 0
Mayhill 51 81 50 82 / 0 0 0 0
Mescalero 48 78 48 80 / 0 0 0 0
Timberon 49 76 50 78 / 0 0 0 0
Winston 45 83 42 87 / 0 0 0 0
Hillsboro 57 84 53 87 / 0 0 0 0
Spaceport 52 87 53 89 / 0 0 0 0
Lake Roberts 38 79 44 83 / 0 0 0 0
Hurley 49 83 46 87 / 0 0 0 0
Cliff 39 88 40 91 / 0 0 0 0
Mule Creek 46 80 47 83 / 0 0 0 0
Faywood 52 82 50 85 / 0 0 0 0
Animas 52 88 48 90 / 0 0 0 0
Hachita 45 87 50 90 / 0 0 0 0
Antelope Wells 53 87 50 90 / 0 0 0 0
Cloverdale 50 82 51 85 / 0 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...Red Flag Warning until 10 PM MDT this evening for NMZ110>113.
Red Flag Warning from 11 AM to 8 PM MDT Monday for NMZ110>113.
Wind Advisory until 9 PM MDT this evening for NMZ402>417.
TX...Red Flag Warning until 10 PM MDT this evening for TXZ055-056.
Red Flag Warning from 11 AM to 8 PM MDT Monday for TXZ055-056.
Wind Advisory until 9 PM MDT this evening for TXZ418-419.
&&
$$
99/99/99
AREA FORECAST DISCUSSION
National Weather Service Sioux Falls SD
1105 PM CDT Sun May 8 2022
.SHORT TERM...(This Evening through Monday)
Issued at 320 PM CDT Sun May 8 2022
GOES-16 early this afternoon shows a broad area of stratus lingering
near and east of the I-29 corridor. Expect this area to regress back
westward through the evening hours as low level WAA increases in
advance of the approaching CO Low.
Hi-res guidance continues to support an area of showers and storms
developing in western and central SD this evening, but this activity
should skirt just west of the forecast area. The bigger impact will
be drizzle and patchy fog spreading north with WAA and stratus
overnight into early Monday as the associated warm front progresses
northward.
Additionally, potential remains for a few isolated strong to
severe thunderstorms from midnight through 6am or so. The most
favorable atmosphere for severe wx will reside north of I-90 as
the warm front lifts through. Plentiful deep layer shear aided by
destabilizing air fed in by a strong LLJ will bring 1000-2000 J/kg
of MUCAPE, making development of elevated storms possible. The
main threats will be hail up to quarter size and isolated damaging
wind gusts to 60 mph with steep mid level lapse rates and
isolated DCAPE values nearing 1000 J/kg.
Main impact in the daylight hours Monday will be the return of
the gusty winds as a very strong, progressive sfc low tracks
through the region, inducing a tight sfc pressure gradient.
Further complicating matters is a strong LLJ at the top 1% of the
NAEFS climatology bringing potential to mix 35-50 mph gusts down
Monday morning across northwest IA and parts of southwest MN ahead
of the sfc low. Issued a Wind Advisory for this portion of the
region, though the timing may need to be adjusted on the back end
depending on how long gusts persist into the afternoon.
Expect stratus to initially blanket much of the region around
sunrise, but drier air should erode this through the morning from
south to north as the sfc low departs northeastward. Efficient post-
frontal mixing with CAA behind the departing system should mix down
a trailing LLJ as well. A majority of model soundings support gusts
peaking 40-55 mph or maybe even occasionally higher at the top of
the mixed layer across much of SD. Thus have also issued a Wind
Advisory for this area from late morning through the early evening
hours and bumped winds and gusts up to a NBM 90th percentile and
HRRR mix.
Despite the drizzly, cloudy start to the day, expect skies to mostly
clear by mid day with some diurnal cumulus in the afternoon.
Westerly winds and insolation will bring breezy highs ranging from
the mid 70s to near 90 degrees. Given propensity to mix
deeper/drier, tweaked dew points drier toward CONSShort. This does
introduce elevated fire danger with gusty winds across much of the
region, especially where fuels remain drier near and east of the I-
29 corridor Monday afternoon.
.LONG TERM...(Monday Night through Sunday)
Issued at 320 PM CDT Sun May 8 2022
Monday`s frontal boundary stalls across WI/IA/southeast NE on
Tuesday, bringing continued dry and slightly cooler weather. Should
be the choice day for outdoor activities for the week given lighter
winds, lower dew points, and highs mainly in the 70s.
We will see a taste of summer weather Wednesday and Thursday with
highs expected to reach at least the 80s across the region. Record
highs are looking increasingly likely south of I-90 on Wednesday and
Thursday, when highs will peak above 90 degrees. Record warm low
temperatures are looking likely Wednesday night as well. This occurs
as broad WAA lifts hot, moist air back north, and upper ridging
reaches heights near the max of NAEFS climatology just to our east.
Fortunately our major swing up into summer heat from upstream ridge
blocking won`t hold for long as a stronger longwave trough pushes
into the Central U.S. by the weekend. Rain chances increase
Wednesday through Thursday night with a few weaker disturbances. The
upper jet moving in on Thursday could bring potential for severe
weather if all of the ingredients align, as highlighted in the
latest SPC outlook. However confidence in any details at this range
is pretty low beyond calling for a breezy Thursday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1100 PM CDT Sun May 8 2022
MVFR/IFR stratus will continue to spread across the area
overnight, and persist through late Monday morning. May also see
areas of drizzle develop where stratus resides. Strong to
severe thunderstorms will push from south central SD into east
central SD from 08Z to 12Z, with large hail possible as well as
erratic stronger winds.
Southeasterly winds will increase overnight, gusting at 20 to 30
kts at times, transitioning to west/southwesterly on Monday
afternoon. Winds then decrease and become northwesterly on Monday
evening.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory from 10 AM to 8 PM CDT Monday for SDZ038>040-050-
052>060-063-064.
MN...Wind Advisory from 7 AM to 4 PM CDT Monday for MNZ081-089-090.
Wind Advisory from 7 AM to 8 PM CDT Monday for MNZ071-072-080-
097.
IA...Wind Advisory from 7 AM to 4 PM CDT Monday for IAZ002-003-013-
014-022.
NE...NONE.
&&
$$
SHORT TERM...BP
LONG TERM...BP
AVIATION...JM
Area Forecast Discussion
National Weather Service North Platte NE
920 PM CDT Sun May 8 2022
.Mesoscale Discussion...
Issued at 920 PM CDT Sun May 8 2022
A deep 988mb surface low is currently located roughly east of
Greeley, Colorado this hour, with a cold front stretching northeast
from the low center. This cold front is draped roughly from just
east of Sidney to just west of Valentine. Rapid moisture advection
is underway across central Nebraska, with dewpoints now in the upper
50s along and southeast of a Broken Bow to O`Neill line. An upper
level wave is currently swinging across portions of the
Intermountain West, with increasing ascent across the Rockies and
into the Plains.
As the upper wave continues to push eastward this evening, the
surface low will begin to eject northeastward out of northeast
Colorado. As this occurs, convective initiation is anticipated near
the cold frontal boundary. With rapidly increasing flow aloft deep
layer shear will quickly increase to near 50-70kts above the
effective inflow base. Any convection looks to remain largely
elevated in nature, which suggests a primarily large hail threat.
High-res guidance continues to hint at robust elevated supercellular
development, largely in the 05-07Z timeframe. This looks to occur
with a strengthening LLJ, with flow increasing to 35-45kts into the
surface frontal boundary. Concerningly, cooling aloft will lead to
quickly increasing MUCAPE as well as steepening mid-level lapse
rates. Latest high-res guidance continues to hint at widespread 1500-
2000 J/kg of MUCAPE for storms to tap into aloft, and this should be
enough to sustain convection amid the very strong shear in place.
Where initiation occurs remains somewhat low confidence, though
there appears to be a window for elevated supercell development
across the western Sandhills into north central Nebraska near/after
midnight. Any supercells that can develop should quickly move
northeastward, with only a limited window of severe potential.
Bottom line remains, confidence continues to slowly increase in the
potential for elevated supercells with a large hail threat over the
next 2-6hrs.
&&
.SHORT TERM...(This evening through Monday night)
Issued at 331 PM CDT Sun May 8 2022
992 mb sfc low pressure near Aspen CO this afternoon will redevelop
across nern Colo and deepen to 985-987 as it is lifted north into SD
by a 75kt 500mb jet tonight. The attendant warm front lifting
through ncntl Nebraska is one area of interest for thunderstorms. A
second area of interest is across nwrn Nebraska where a stationary
front will be located. Storms in both areas, if they develop, will
be mostly elevated.
Winds aloft will become strong at h500mb, 50-65kt, representing a
very strongly sheared environment. In fact, the bulk Richardson
number in the RAP and NAM models is less than 5. This suggests
the updrafts will be sheared apart defeating the potential for
near-sfc based severe storm development. A check on elevated
instability, however, suggests the potential for elevated storms
in the NAM but not the RAP. The forecast favors the NAM/NAMnest
which suggests an isolated severe storm or two may form across nrn
Nebraska.
The rain forecast tonight follows the short term model blend which
is trending north maintaining the better chances across SD. Isolated
POPs are in place along and north of highway 2 in Nebraska which
increase to 40-60 percent near the SD border.
All of this rain should exit the region by Monday morning. The
models are in very good agreement sending a surge of very dry air
into wrn and ncntl Nebraska Monday- RH falls to below 30 percent and
west winds increase to 15 to 30 mph.
As the 984 mb sfc low pressure pulls away from Nebraska Monday, the
RAP shows 30 to nearly 40kt winds at 500m AGL developing across the
wrn Sandhills. The GFS, HRRR and RAP show gusts around 50kts and the
GFS BUFkit soundings show mixing heights approaching 600 mb which
could tap into the 65 to 80 kt winds at that level. It is important
to note the 600 mb winds shown are not unidirectional with the 700mb
winds suggesting the potential gusts could be less.
The culprit is the -32 to -34C h500mb cold pool the models show
forming over the West Coast or OR/nrn CA. This is near record cold
according to SPC UA climo. The wind forecast is guarded for this
reason and a High Wind Watch is in place across parts of wrn Neb.
Monday.
.LONG TERM...(Tuesday through Sunday)
Issued at 331 PM CDT Sun May 8 2022
The next chance of severe weather develops Wednesday and
Thursday. The models are in very good agreement developing sfc low
pressure to the lee of the Colorado Rockies and lifting a warm
front through Nebraska Wednesday. The warm front is the basis for
isolated- scattered thunderstorm chances. The NAM, ECM and GFS
suggest isolated storm coverage and this is because of the 12C
temperatures and resulting cap at h700mb. The storm mode is within
the forecast range of the NAM model and BUFkit suggests
conditions will be favorable for longer-lived supercells. The
3000-4000ML CAPE and 40-50kt 500mb winds should provide a good
balance for rotating updrafts.
The storms develop Thursday when the sfc low pressure lifts north of
Nebraska and pushes a dryline east toward ncntl Neb. Winds aloft
strengthen a bit, perhaps 60kt or stronger at h500mb and the cap
should weaken supporting scattered storm coverage, mainly east of
highway 83.
The forecast Tuesday, Friday and Saturday is dry and uneventful.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 619 PM CDT Sun May 8 2022
Multiple aviation weather concerns exist for western and north
central Nebraska through Monday afternoon. Tonight, scattered
thunderstorms develop in northwest Nebraska and spread east
(affecting KVTN). Farther south, conditions remain but a stratus
deck may briefly work into KLBF. In addition, low level wind shear
conditions are expected. Higher confidence in low ceilings,
including MVFR/IFR, lies across the north. Toward early morning
Monday, a cool front helps to clear out the low clouds. It also
results in a wind switch to west/northwest and a rapid upswing in
speeds. The strongest gusts will be across northern Nebraska where
gusts may approach 40 kts.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
High Wind Watch from 9 AM CDT /8 AM MDT/ Monday through Monday
evening for NEZ004-005-022>025-035-094.
&&
$$
Mesoscale...Brown
SHORT TERM...CDC
LONG TERM...CDC
AVIATION...Snively
Area Forecast Discussion
National Weather Service Memphis TN
718 PM CDT Sun May 8 2022
.UPDATE...
7PM Update
No major changes were made to the previous forecast. Did add in a
chance for some very patchy fog along the TN River Valley for a
couple hours in the morning. Otherwise the heat is on for the rest
of the week!
SMW
&&
.PREV DISCUSSION... /issued 226 PM CDT Sun May 8 2022/
DISCUSSION...
A gorgeous day across the Mid-South today for Mother`s Day,
few clouds, temperatures in the 70s and light winds in most
places. Enjoy this weather while it lasts as the upper ridge that
is building over the Mid-South will become entrenched over the
area and will allow the temperatures to rise to record high levels
across the area.
An upper ridge builds over the area the next couple of days and an
associated surface high stays in place providing little
instability for clouds, yet allows the days to be warmer.
Monday should have highs generally in the 80s with the exception
of areas in Mississippi Delta in Arkansas and Mississippi. The
upper ridge builds enough by mid-week to be an upper level high
which will allow for temperatures to rise into the 90s. The
current forecast has record high temperatures on Wednesday and
Thursday. All four climate sites (Memphis, Jackson, Jonesboro, and
Tupelo) either tie or break the record highs for Wednesday and
Thursday.
On Thursday the upper ridge begins to weaken as the upper level
trough currently off the east coasts begins to move west and by
Friday brings some relief to the temperatures, yet most areas
will be in the 80s.
The moisture through this coming week will have dew points in the
mid 60s, which is lower than typical summer dew points--in the
70s--. Yet it will be hot and humid and people will have to be
cautious in the outdoor activities. Especially since we haven`t
really had warm weather this year.
As the upper low moves west from the east coast there may be
enough instability to bring some showers to the area. However,
the different models are very consistent on this solution, so
have left the PoPs low.
TLSJr
&&
.AVIATION...
00Z TAFs
Primarily a wind forecast over the next 30 hours, as southeasterly
winds veer to the south and strengthen through a combination of
tightening low level pressure gradient and daytime mixing on
Monday.
For the overnight, winds should stay up enough to keep fog from
persisting too long at the ASOS vis sensors at MKL and TUP. HRRR
and NAM Bufr soundings depict a broken deck around FL015 lifting
up the delta after 12Z, but have held sky condition to scattered
and flight conditions to VFR for now.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
654 PM CDT Sun May 8 2022
.UPDATE...
Issued at 642 PM CDT Sun May 8 2022
Updated for 00z aviation discussion.
&&
.DISCUSSION...(This evening through Sunday)
Issued at 305 PM CDT Sun May 8 2022
Key Messages:
- Chance for thunderstorms in western Minnesota tomorrow morning,
with another round possible in eastern Minnesota to western
Wisconsin tomorrow afternoon/evening.
- Gusty winds tomorrow peaking at 40-45mph south of the Minnesota
River. Elevated fire weather conditions in the same area.
- Trend for hot weather continues for midweek with highs likely
reaching the upper 80s to lower 90s by Thursday.
- Occasional thunderstorms chances through the week with the most
widespread activity Wednesday night.
THIS EVENING THROUGH MONDAY...Satellite this afternoon continues to
show a thick area of low clouds over most of MN/WI with a small
amount of clearing in the eastern Twin Cities to New Richmond WI. A
synoptic scale trough is evident over the western CONUS on water
vapor imagery, with falling h850/h500 heights likely in western
Minnesota due to the trough moving eastwards over a developing
surface low producing scattered showers and thunderstorms by 7am
tomorrow morning. Rain chances have overall decreased for the
remainder of today, although some isolated showers remain possible
which at most would slightly disrupt any outdoor plans. Breezy winds
continue and increase further as the developing system moves closer,
with a Wind Advisory being issued for tomorrow south of the Minnesota
River due to wind gusts of 40-45mph out of the south.
Around sunrise tomorrow, the 18z HRRR and a few other CAMs are
producing a few elevated storms which have the potential to drop
severe hail, with forecast soundings from the RAP/NAMNEST showing
1000-1500 J/KG MUCAPE with mid to upper level lapse rates of 7 to 7.5
C/km, which would be more than enough to produce hail if we can get a
storm going. Due to a weak surface inversion left over from the
night, it is unlikely that we see any significant storm gusts,
however synoptic scale gusts will be increasing during that time
frame regardless. This will mainly be an issue for our far western
CWA from Canby to Alexandria heading towards northwestern Minnesota
quickly, out of the area by 9-10am. A second round of storms looks
possible later in the afternoon and evening originating near or east
of the Twin Cities and primarily moving through western WI. NAM
soundings show around 500-1000 J/KG MLCAPE with 35-40kts of low level
shear and 300-350 m2/s2 SRH due to strong surface winds. We do have
curved hodographs but weak lapse rates at or below 6.5 C/km should
keep our hail threat limited, with intense WAA also keeping a healthy
amount of CINH in the area as well. The expectation is for weak
storms producing a bit of lightning but no significant severe weather
threats in western WI, but we will have to take another look once the
system moves closer and we have some fresh observed soundings at 00z
tonight and 12z tomorrow morning.
TUESDAY AND WEDNESDAY... A brief period of high pressure will build
across the region on Tuesday as a weak boundary sets up to the
southeast. This boundary will be the focus for a small chance of
thunderstorms. On Tuesday night this boundary will start to lift
northward across the region, and so too will the small chances for
thunderstorms. This warm front will continue to push north on
Wednesday, so did decrease rain chances across the south. Highs
should manage the mid 80s across much of the region. On Wednesday
night the low level jet should lead to storms developing north of
this boundary. There is still some uncertainty where exactly that
will be, but chances are highest north of I-94. A few storms could
be strong to severe and pose a heavy rain risk if training occurs.
THURSDAY THROUGH SUNDAY... Depending on how the convection develops
Wednesday night, Thursday looks to be the warmest this week with
afternoon highs close to 90 possible. A weak cold front will
approach from the west Thursday night into Friday. This will bring
more thunderstorms chances, and cooler, more seasonable air. The
Storm Prediction Center has a small severe risk area along the
MN/Dakota border. Looking ahead, this cooler air will last into the
weekend as highs return back to the 70s for Saturday and 60s for
Sunday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 642 PM CDT Sun May 8 2022
Ceilings continue to degrade this evening, with MVFR conditions
ongoing at most Minnesota terminals. This trend will continue through
the evening, with IFR ceilings expected by the overnight hours at
western & central MN sites and MVFR ceilings at MSP & WI sites. A
band of showers and thunderstorms will move through west-central
Minnesota early tomorrow morning, with AXN & STC the mots likely
sites to see MVFR rain. There is a risk for a strong to severe
thunderstorms during this time as well, especially at AXN. Ceilings
will remain MVFR/IFR through the morning, finally scattering out as a
front and wind shift moves through the region during the mid to late
afternoon. There is a chance for another round of thunderstorms to
develop along this front late tomorrow afternoon, with RNH & EAU the
most likely sites to see any potential impacts from thunder.
Winds will stay southeasterly overnight into tomorrow morning, with
gusts around 20 kts tonight. Speeds increase tomorrow morning, with
sustained winds of 20-25 kts and gusts of 30-40 kts likely through
the morning and afternoon. A wind shift to southwesterly is expected
during the afternoon, wit winds remain gusty into the evening.
KMSP...MVFR ceilings are expected through tomorrow morning, with a
small chance of IFR tomorrow morning. Ceilings under the 017
threshold are likely during the morning. Southeasterly winds will
increase during the early morning, with gusts of 30-35 kts expected
through the morning and afternoon. A wind shift to southwesterly is
expected between 22-00Z with gusts finally diminishing after sunset.
There is a low (10-20%) chance of thunderstorms developing along the
frontal passage late tomorrow afternoon.
/OUTLOOK FOR KMSP/
TUE...VFR. Wind NE 5-10kts.
WED...VFR. Chc MVFR/IFR in SHRA/TSRA late. Wind SE 10G20kts.
THU...VFR/MVFR, chc SHRA/TSRA. Wind SE to SW 10-15G25kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...Wind Advisory from 7 AM to 4 PM CDT Monday for Blue Earth-Brown-
Faribault-Freeborn-Lac Qui Parle-Martin-Redwood-Steele-Waseca-
Watonwan-Yellow Medicine.
WI...None.
&&
$$
DISCUSSION...JRB/TDH
AVIATION...ETA
Area Forecast Discussion
National Weather Service Spokane WA
349 PM PDT Sun May 8 2022
.SYNOPSIS...
The Inland Northwest will experience cool and showery weather much
of the week. Temperatures will be well below average this week
with areas of morning frost Monday through Thursday. Next weekend
should be warmer with highs in the 60s on Saturday and upper 60s
to near 70 on Sunday.
&&
.DISCUSSION...
Tonight through Tuesday Night: There is good model agreement that
a closed low over the Columbia Basin this afternoon lifting
northeast into NW Montana Monday morning. With the low over the
region today instability showers are covering a broad area with
reports of mainly rain and graupel from the showers but also a few
reports of small hail as well as mountain snow. The colder
atmosphere hasn`t been as conducive to thunderstorms although a
few strikes will be possible through the early evening hours. The
best potential looks to be over the Okanogan Highlands, and from
the Blue Mountains into the Central Panhandle Mountains with RAP
analysis is showing the highest surface based CAPE values of
300-600 J/KG. Most of these showers will come to an end around
sunset with the loss of daytime heating. But this won`t be the
complete end.
As the low moves into NW Montana some wrap around moisture swings
into the Idaho Panhandle and NE Washington late tonight into
Monday morning. There remains some model and ensemble disagreement
with the coverage and intensity of this wrap around moisture.
Some solutions show a wetter scenario with localized 0.25-0.50" of
liquid precipitation but the majority shows a lighter precip
event of 0.05-0.20". The GFS and GEFS are some of the wetter
solutions and since the GFS is showing more moisture over northern
WA compared to what satellite/radar indicate the forecast sides
towards the lighter amounts. With snow levels dropping as low as
2000-2500 feet Monday morning some wet snow is possible but
accumulations should stay confined to the mountains given the
warmer ground temperatures of early May. For Monday afternoon and
Tuesday a broad trough lingers over the region which will support
mainly diurnally driven showers. There remains enough instability
over the northern mountains Monday afternoon for a few short
lived thunderstorms.
Lastly...the trough over the area will promote cool overnight
lows with near freezing temperatures for several locations. For
where the growing season has started with near freezing
temperatures a frost advisory has been issued for tonight/Monday
AM. A near repeat performance is likely Tuesday and Wednesday
morning as well. JW
Wednesday to Sunday: After dry weather Wednesday, the next system
moves in for the end of the work week, before drying out again
next weekend. Overall the pattern looks somewhat progressive as
ridge migrates by for midweek, with those continued cold and frost
mornings.
The next trough approaches the coast Wednesday night into morning
Thursday, then starts to make its way inland Thursday afternoon
into Friday. Timing could change as it is still several days out.
Overall precipitation chances increase near the Cascades into
Thursday AM, then expand across all of the area Thursday afternoon
into Thursday night. Temperatures support largely valley rain and
higher mountain snow, but some snow could mix down to some
valleys on the tail end of the precipitation going into Friday
morning. On Friday the primary precipitation chances start to
retreat to the mountains, but the forecast will need to hold onto
some potential outside of the mountains in the unstable upper
trough where hit-and-miss showers are possible. Overall
instability is present but not overly intense, so the potential
for thunderstorms is not absent but confidence is low at this
moment. This will be monitored as a change in timing could bring
the precipitation potential more in line with better instability.
The weekend will see drier weather, aside from some lingering
shower chances near the Idaho Panhandle mountains Saturday.
The progressive pattern will feature some breezy conditions,
especially Thursday and Friday afternoon. Winds gusting near 15 to
30 mph will be possible, strongest near the Upper Columbia
Basin/West Plains south to the lower Palouse ane lee of the Blue
Mountains.
Temperatures will remain below normal through most of this period,
but start to approach closer to or may be slightly above normal
toward next Sunday. /Cote`
&&
.AVIATION...
00Z TAFs: Shower activity will decrease after sunset with the loss
of daytime heating. As an area of low pressure pushes east
overnight a band of precipitation may drop south on the back side
of the low towards the Spokane area and North Idaho Panhandle
airports Monday morning. Models have big differences regarding
intensity, coverage, and duration of the precipitation with low
confidence in the details. Current forecasts follows a blend of
the short term model guidance. Given cold temperatures a rain/snow
mix is possible but will likely not accumulate even on grassy
surfaces unless heavy (low confidence). Most likely the area of
steadier precipitation will shift north and east of KGEG/KSFF/KCOE
in the afternoon although the GFS is an outlier in maintaining
precipitation into the afternoon. JW
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 34 51 34 56 33 59 / 20 40 20 10 10 0
Coeur d`Alene 34 48 34 54 34 58 / 20 50 20 10 10 0
Pullman 33 49 34 53 34 56 / 20 20 10 10 10 0
Lewiston 38 56 38 60 36 64 / 20 10 10 10 0 0
Colville 34 53 33 57 32 61 / 40 50 40 20 10 0
Sandpoint 35 46 35 52 34 57 / 40 70 40 30 20 0
Kellogg 34 45 33 51 32 56 / 20 50 20 20 10 0
Moses Lake 34 59 35 63 35 64 / 10 0 10 0 0 0
Wenatchee 39 56 38 60 39 62 / 20 10 0 0 0 0
Omak 37 58 35 63 38 64 / 20 20 10 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Frost Advisory from 11 PM this evening to 8 AM PDT Monday for
Coeur d`Alene Area.
WA...Frost Advisory from 11 PM this evening to 8 AM PDT Monday for
Moses Lake Area-Spokane Area-Upper Columbia Basin.
&&
$$
Area Forecast Discussion
National Weather Service Blacksburg VA
1030 PM EDT Sun May 8 2022
.SYNOPSIS...
High pressure will remain established across the Mid-Atlantic
into North Carolina through much of the workweek, maintaining
generally dry conditions. Temperatures will gradually moderate
as the week progresses. Rain chances will increase on Friday as
low pressure begins to draw Atlantic moisture westward across
the Appalachian chain.
&&
.NEAR TERM /THROUGH MONDAY/...
As of 1020 PM EDT Sunday...
...Frost Advisory Expanded to Include the Southern Shenandoah
Valley and the New River Valley...
Skies are clearing west of the Blue Ridge this evening and are
expected to clear east of the Blue Ridge overnight, possibly
persisting in the Danville and northern NC area for several more
hours. Winds are forecast to diminish down through the
Shenandoah Valley, Greenbrier Valley, and New River Valley.
Temperatures are dropping more than expected in these areas and
easily could reach the lower to mid 30s if all of these
conditions remain in place. Wind is the main concern to prevent
frost formation overnight, especially in far southwest Virginia
where it should remain higher. With all of this in mind, have
expanded the Frost Advisory to include these additional areas
further southwest. Only very isolated locations will potentially
make it to the freezing mark, such as Burkes Garden.
As of 750 PM EDT Sunday...
Weather Conditions Continuing to Improve Through Monday...
A large area of low pressure continues to spin off the Mid-
Atlantic coast and will essentially move very little through
Wednesday, then begin to drift to the southwest toward GA. This
will keep the region in a cool, moist, northeast to east maritime
flow over the next few days. As surface winds come around more
to the northeast as opposed to the east, the pesky stratus layer
has been eroding from the northwest and west. Not confident
with night fall that this will continue at the same rate as
currently, but the erosion has occurred a bit quicker than
earlier expected, so will lean toward the optimistic side and
accelerate the clearing west of the Blue Ridge this evening.
With respect to the Frost Advisory and the potential to need to
expand into the Shenandoah Valley, plans are to wait until the
8-9 PM EDT hour to assess the current state of temperatures,
cloud cover, and wind at that point. Current thinking is that
wind will be a bit too much for any widespread frost in those
areas and not even totally convinced of the same in the
Greenbrier Valley, although it will be a bit colder there and
potentially clear.
The other factor to watch overnight is the development of ground
fog. HRRR really wants to hit this hard through the Greenbrier
and New River Valleys after 06Z. Ground is moist, but again feel
wind may be a bit too much for any widespread ground fog. In
addition, river fog less likely given the water is fairly cold
and relatively close to the air temperature at this time of
year.
As of 220 PM EDT Sunday...
Surface observations indicate high pressure extends southward
from eastern Canada through the Mid-Atlantic and the Carolinas.
Northeasterly winds around the high continue to draw
unseasonably cool air across our region, with temperatures this
afternoon holding in the low to mid 50s. A stubborn layer of low
clouds is limiting the potential for increased daytime heating,
though satellite imagery indicates clouds beginning to scatter
across portions of Greenbrier County in West Virginia, as well
as Smyth and Tazewell Counties in far western Virginia. It is in
these areas where we may see a late afternoon spike in
temperatures into the upper 50s with prolonged sunshine.
Low clouds will gradually diminish overnight to mostly clear
skies by dawn as drier air moves in from the northeast. Can
also expect wind speeds to decrease as low pressure situated
off the Atlantic coast drifts further away. Given the cool
airmass in place, some potential exists for patchy fog to
develop toward dawn where clouds clear out. Better chances for
patchy frost appear to be around the Greenbrier Valley where
overnight lows will be coolest, and have issued a Frost
Advisory as a result. Elsewhere, conditions appear to be less
favorable for frost where temperatures will remain a little too
warm or winds remain a little too breezy. Regardless, with
temperatures for many across the mountains falling into mid 30s
tonight, it may be prudent to play it safe and offer any
sensitive vegetation some form of shelter from the overnight
chill.
Given more-abundant sunshine for Monday, daytime temperatures
will be several degrees warmer that those observed today, albeit
still maxing out below normal for the 2nd week of May. Look for
highs to range from the mid 60s to near 70 across the region.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 1236 PM EDT Sunday...
A dry start the workweek with warming trend.
A closed upper level low will linger over the western Atlantic Ocean
Monday night into Wednesday. At the same time, the upper ridge will
build northeast from the Gulf of Mexico to the New England. Surface
Canada high pressure will build southward into the Appalachians to
continue the dry weather. A northeast flow will continue because of
the pressure gradient between the high center to the north and low
center off in the Atlantic.
Temperatures will moderate as the week progress due to subsidence
and plenty of sunshine.
High confidence in the Short Term Forecast.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 1236 PM EDT Sunday...
Rain returns for the Weekend.
Blocky pattern will persist across the East Coast into Friday due to
a closed upper level low center spinning off the North Carolina
coast that is trapped southward of an upper level ridge over eastern
Canada. The low will slowly wobble towards the southwest. The Mid
Atlantic region should remain dry into Thursday evening. As the low
come ashore to our south, the chance of showers increase Thursday
night into Friday.
The combination of the ridge building out west and an upper level
trough approaching from the Plains should end the Rex block
during the weekend. This should allow the closed low to move
northward Friday into Sunday. The weekend ahead looks cloudy
with showers and thunderstorms.
Moderate confidence in the Long Term Forecast.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
As of 800 PM EDT Sunday...
VFR Conditions Expected to Return This TAF Valid Period...
Synopsis: Deep upper low pressure will linger off the Mid-
Atlantic coast for the next several days with high pressure
anchored across the northeastern U.S. This pattern will result
in a persistent cool, northeasterly maritime flow across the
region for the next several days. Drier air will be advected
southwestward into the region overnight from the northeastern
U.S. allowing the pesky marine stratus layer to be pushed
further south/southeast out of the RNK CWA. Eastern areas of the
CWA will hold onto the stratus the longest and potentially much
of the night.
Ceilings: Clearing has advected southward into BCB/BLF/LWB this
hour. Unusual to see clearing of stratus from this direction,
but this is a result of the drier northerly flow from high
pressure across PA/NY, while eastern areas hang onto the
stratus better with upslope along the Blue Ridge. Drier air is
expected to continue advected southwestward into the region
overnight. VFR ceilings have returned to most areas west of the
Blue Ridge as of 00Z and are expected to gradually return to
areas east of the Blue Ridge overnight/early Monday. In
addition, as drier air advects southward, ceilings will rise to
AOA 030. KDAN and KLYH will likely hang onto the stratus the
longest primarily in the 030-035 range.
Visibility: At this time, not expected to be an issue. However,
HIRES near term models, such as the HRRR, suggest ground fog may
develop through the Greenbrier and New River Valleys toward
morning. Confidence in this is low at this point given dry air
advection from the north/northeast and persistent northeast
flow. Will monitor, but not including any fog at the TAF sites
at this time. KLWB would be the most susceptible to such due to
clear skies and lighter wind and cool air drainage from the
northeast.
Winds: Remaining Northeast to East through the TAF valid
period, trending a bit more toward the North late in the TAF
valid period. Speeds 5-10 mph overnight, 8-13 mph Monday with
low end gusts, especially east of the Blue Ridge.
/Confidence Levels in Forecast Parameters/
- Moderate Confidence in Ceilings,
- Moderate to High Confidence in ,
- High Confidence in Wind Direction and Speed.
Extended Aviation Discussion...
The large upper low will remain off the Mid-Atlantic coast
through Wednesday and then drift slowly south to southwest
during the later half of the week. By the weekend into early
next week, the upper low will become caught up in the westerlies
and a fast moving short wave tracking out of the Midwest Sun-
Mon. Showers and thunderstorms will return to the area at that
time. In the meantime, however, dry northeast flow will remain
over the region with upper ridging just to our west. Conditions
will be mainly VFR through the period until the weekend. Late
night and early morning patchy fog will be possible in the usual
locations (e.g., KLWB and KBCB...) as the week progresses.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...Frost Advisory until 9 AM EDT Monday for VAZ010>014-017>020-
023-024.
NC...None.
WV...Frost Advisory until 9 AM EDT Monday for WVZ042>044-507-508.
&&
$$
SYNOPSIS...NF
NEAR TERM...NF/RAB
SHORT TERM...KK
LONG TERM...KK
AVIATION...RAB
...Update to aviation forecast discussion...
.DISCUSSION...
Issued at 229 PM CDT Sun May 8 2022
Some mid-level enhancement from convection to the north was able
to squeeze some very light precip out of the saturated lower-level
atmosphere early this morning and left some holes in the stratus
deck into the early afternoon. One notable hole was in central
Kansas where modest convergence was taking place and dewpoints
were around 70. Bulk shear would be enough with ML CAPE near 3000
J/kg to support a severe storm if one can form, though RAP
soundings look to be breaking down the EML rather aggressively
this afternoon. Will need to watch this area for the next several
hours. Elsewhere dewpoint depressions are likely high enough to
keep drizzle or sprinkles from being more than brief and very
spotty.
The main story for most parties through the middle of the week will
be anomalously-warm temperatures. A stout low-level jet will build
in each night and continue to bring warm and somewhat humid air into
the area. ESAT data continues to show 500 MB heights and mid/low-
level temps near to at extreme levels through Thursday. Record high
and warm minimums are quite possible (see below for current record
details).
There are a few other items to note however. Dry air is on track to
surge northeast across central portions of Kansas during the day
Monday as a strong surface low moves north though the northern
Plains. Relative humidity levels fall into the 15-20% range in the
afternoon with winds on the breezy side. Weather criteria support
fire weather headline potential, but per coordination with fire
weather partners, grasses have responded enough to recent rains
to no longer support extreme fire behavior. Much of north-central
Kansas will see Very High indices Monday afternoon. A weak cold
front looks to hang up just north of the area Monday night and
some guidance attempts to generate precipitation near it as far
southwest as northeast Kansas, though inspection of forecast
soundings show this to be unlikely. Have kept some small mention
there for now.
The next best precip chances come Thursday night into Friday night
as multiple waves in the northwest CONUS break down the ridge and
bring a cold front through. Upper support appears modest and severe
potential is not great. Temperature finally fall to around normal by
Saturday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 618 PM CDT Sun May 8 2022
Ceilings are currently mostly VFR, though a few pockets of broken
MVFR ceilings will linger over the next couple hours before
gradually clearing out overnight. Winds will turn from southeasterly
tonight to the south-southwest by mid-day tomorrow, sustained at 13
to 17 kts with higher gusts. Some 50 to 55 kt LLWS will once again
be present overnight, as a southerly 60 kt LLJ ramps up again.
&&
.CLIMATE...
Issued at 229 PM CDT Sun May 8 2022
Daily record temperatures of note this week:
Record High Record Highest Minimum
----------- ----------------------
Monday, May 9
Topeka 95 in 2011 72 in 1996
Concordia 100 in 1895 72 in 1956
Tuesday, May 10
Topeka 92 in 2011 75 in 2011
Concordia 98 in 1895 70 in 2011
Wednesday, May 11
Topeka 95 in 2000 69 in 2018
Concordia 93 in 2000 65 in 1970
Thursday, May 12
Topeka 93 in 1956 73 in 2018
Concordia 99 in 1956 72 in 1956
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...65
AVIATION...Reese
CLIMATE...65
Area Forecast Discussion
National Weather Service Las Vegas NV
1143 AM PDT Sun May 8 2022
.SYNOPSIS....Widespread strong winds will diminish tonight.
Additional weather systems will continue to move through the
Great Basin through midweek, with temperatures trending cooler and
blustery weather persisting. A warming trend will commence for
the second half of the week with winds easing as high pressure
gradually rebuilds across the region.
&&
.SHORT TERM...Tonight through Monday.
Strong winds will continue to impact the region through the evening
and early overnight hours across the region as an upper level trough
digs south. The strongest winds should be centered around 00Z as a
strong vorticity lobe advects into the southern Great Basin. Areas of
concern through the evening for wind impacts:
[LAS VEGAS/SPRING MTS/SOUTHERN NV]: Models continue to show the
strongest west winds pushing through the valley around 00Z, though
there continues to be discrepancy in the model wind speed forecasts
and how far west the stronger winds will spread. Hi-res local model
cross-sections are a bit more favorable for downslope winds compared
to previous runs with west winds pushing through at least Red Rock
and Summerlin around 3-6 PM. The 15-min HRRR brings the strongest
wind gusts through Harry Reid Airport around the same time. NBM
probabilities for wind gusts over 60 MPH have come up for all areas
west of the I-15, but remain low for the east portion of the valley.
Given this meterologist`s past experience in forecasting west wind
events in Las Vegas, I have moderately high confidence that strong
winds that mimic waves that will move across the entire valley at
times this afternoon and evening, with gusts coming up quickly
followed by a lull before another jump in wind gusts (and
rinse/repeat through the evening hours). This wave pattern is noted
on a few wind model fields. Mentioning all this just because even if
all portions of Las Vegas don`t hit 60 MPH, the nature eof the winds
could drive impacts and people should be prepared for sudden gusty
winds and strong crosswinds, especially on north-south roadways in
and around the valley.
The Spring Mountains and Red Rock will see strong winds through the
evening. Gusts up to 60MPH may cause downed trees and power outages,
and more importantly dry conditions would mean any fire starts would
quickly spread. Further south, gusty winds across I-15 and US-95 are
likely this afternoon with dust concerns as winds push through the
dry lake beds in southern Nevada. Lake Mead will see west winds
gusting 40-50MPH this afternoon and thus dangerous waves are likely
and any light or small boats on the lake shores could easily be
pushed into the lake as winds come up.
[OWENS VALLEY]: Continued high confidence for sudden wind gusts
across the highway and difficult travel through 7-9PM. Best
downslope potential is after 21Z through 02Z.
[DEATH VALLEY]: Some of the wind models bring a push of north winds
through Death Valley after 21Z. While the wind speed forecast has
not changed with this wind push, if these winds come through
suddenly it may result in additional impacts due to dust in Death
Valley and areas southwest of them this afternoon after 3PM.
[MOHAVE NORTH OF I-40]: This is the area where winds and impacts may
outperform as models continue to have a wide spread on peak winds
and how long they will last. Currently thinking that any strong
winds will be short lived, and a Wind Advisory communicated well the
risk with these winds, but low confidence in those details. In
addition, if sudden winds or stronger winds develop, dust will
likely impact areas north and west of Kingman. The best chance for
60 MPH or greater gusts will be through the Arizona Strip in the Mt
Trumbull and northern Hualapai Nation region.
Winds will diminish tonight. No changes were made to the wind
headlines and for the most part they look to be in good shape. San
Bernardino may drop below High Wind Warning criteria later this
evening but wind impacts will continue through the night and
potentially even Monday morning. Winds on Monday will be breezy
again as the upper level trough that brought winds today continues
to meander through the region, but the pressure gradient is expected
to slack somewhat overnight and thus winds will be lower tomorrow
compared to today. The best chance for wind impacts will be in the
West Mojave Desert, southern Inyo County, and southwest Nevada. A
wind advisory may be needed for Monday in these areas. In addition
to the wind advisory, critical fire conditions are possible on
Monday in portions of the region as it will continue to be dry,
though winds will be marginal for another Red Flag Warning. Will
hold off adding more headlines at this time and will let that
decision fall to later shifts as impacts on Monday should be minor
and we should first see how today`s wind event pans out.
Temperatures will continue their downward trend on Monday, with high
temperatures 5-10 degrees colder on Monday compared to today.
.LONG TERM...Tuesday through Saturday.
Model solution clusters show very good agreement that the trough
which plagues our region with wind through the short term will
still be in place along the West Coast Tuesday, leading to still
more southwest winds and below normal temperatures areawide. Wind
Advisories cannot be ruled out. Wednesday looks similar, with
unseasonably cool temperatures and gusty winds, possibly reaching
advisory levels, as the trough tracks slowly east. A solid
majority of model solutions then show the trough minoring out and
lifting away, leading to rising heights Thursday through Saturday,
which would drive temperatures back above normal, but more
importantly, provide a respite from the relentless springtime
winds. There have been a few events already this spring in which
long range models de-emphasized low pressure heading toward the
West Coast, only for future model runs to finally catch on to a
deeper, cooler, and windier solution which ended up verifying. So,
while the good model agreement noted above justifies optimism, it
is not a guarantee.
&&
.FIRE WEATHER...Strong southwest winds will continue through this
evening, with wind gusts of 40-60 mph expected across much of the
region. These winds will be combined with low humidity and dry
fuels resulting in widespread critical fire weather conditions.
Winds will ease late tonight but resume each afternoon through at
least Wednesday, though they will not be as strong as today`s
winds. Near- critical fire weather conditions possible each day
through midweek before lighter winds return for the second half
of next week. Cool temperatures are expected through Wednesday
before temperatures quickly warm the second half of the week.
&&
.AVIATION...For Harry Reid...Significant wind event still expected
today across the Las Vegas Valley impacting the Harry Reid terminal.
Initially southerly wind gusts will shift to the southwest early in
the afternoon and increase in gust potential...as high as 50 kts by
the middle of the afternoon. Airport Weather Warnings will be likely
if these gusts indeed come to fruition this afternoon. Additionally,
BLDU could reduce visibility to MVFR conditions during peak winds.
These winds should begin to subside just before sunset and gradually
decrease through the evening and overnight hours. A shift to
northwest winds is expected early tomorrow morning, but confidence
is low in direction as winds will be light.
For the rest of southern Nevada, northwest Arizona and southeast
California...Significant wind impacts are expected over the next 12
hours for much of the region, resulting in poor flying conditions
for all regional terminals. KDAG will maintain westerly winds
throughout but likely will experience lowered visibility due to BLDU
and gusts over 50 kts this afternoon. KBIH will continue to see
strong downslope and potential low level shear/rotor issues
resulting in significant turbulence in addition to strong surface
winds. KIFP/KEED should be more minor regarding winds but will still
remain gusty over 30 kts.
&&
.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&
$$
SHORT TERM/FIRE...Nickerson
LONG TERM...Morgan
AVIATION...TB3
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