Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/18/24
Area Forecast Discussion...Updated
National Weather Service Lincoln IL
730 PM CDT Mon Jun 17 2024
.KEY MESSAGES...
- Seasonably hot and humid weather will prevail this week. Heat
index values will peak in the upper 90s to around 100 degrees
Tuesday afternoon through Saturday afternoon.
- Isolated thunderstorms will be possible from time to time over
the next few days...with a better chance for thunderstorms
arriving late Saturday into Sunday.
&&
.UPDATE...
Issued at 730 PM CDT Mon Jun 17 2024
Much of the lingering convection has faded away, with just a few
showers left that are approaching Flora. However, high-res models
continue to hint at some redevelopment after midnight over the
eastern CWA, with a weak upper disturbance lifting out of the
lower Mississippi Valley. The NAM Nest has been most bullish in
this regard, though the HRRR has had a bit of an uptick recently
as well. PoP`s have been refined a bit with timing, and to
increase them to around 30% near/east of I-57 after midnight. A
large part of the forecast area should be mostly cloudy as well,
with plenty of high clouds streaming northeast. Temperatures are
generally on track to drop into the mid 70s once again.
Geelhart
&&
.SHORT TERM...(Tonight through Tuesday Night)
Issued at 307 PM CDT Mon Jun 17 2024
19z/2pm radar imagery shows isolated convection across the KILX
CWA...particularly east of I-57 and west of the Illinois River.
The isolated storms will persist until sunset, followed by dry
conditions from mid-evening through much of the overnight period.
CAMs have consistently been showing renewed convective development
associated with a subtle short-wave trough pivoting northward
from the lower Mississippi River Valley late tonight into early
Tuesday morning. Based on model consensus, it appears most of the
activity will focus along/east of I-57 after 09z/3am. Have included
20-30 PoPs across this area accordingly. After the early morning
showers fade, disorganized diurnal convection will re-develop
within the highly unstable airmass Tuesday afternoon. Areal
coverage will remain quite low, so have only included 20 PoPs at
this time. Lows tonight will only drop into the lower to middle
70s while highs on Tuesday will climb into the lower 90s. Maximum
heat index values will peak in the upper 90s to around 100 degrees
Tuesday afternoon.
Barnes
.LONG TERM...(Wednesday through Next Monday)
Issued at 307 PM CDT Mon Jun 17 2024
Upper high currently centered over the Carolinas will build
southwestward over the next couple of days, cutting off the flow
of deep-layer moisture from the Gulf of Mexico. With this moisture
shunted into Texas and remaining well S/SW of central Illinois,
diurnal storm chances will decrease Wednesday through Friday. Will
need to keep an eye on a weak cold front that will try to drop
southward out of the Northern Plains, but think most of its associated
convection will remain N/NW of the area across Iowa/Wisconsin.
Have confined low chance PoPs to locations along/northwest of the
Illinois River during that period, but think most locations will
remain dry. Main story will be the hot weather as heat index
values routinely peak at around 100 degrees. Hottest days will
likely be Friday/Saturday when air temperatures climb into the
middle and perhaps upper 90s in a few spots and heat index values
reach 100-105 degrees.
As has been advertised by the models for the past several runs, a
significant short-wave trough is expected to traverse the country
and push a cold front into central Illinois this weekend. 12z Jun
17 GFS and ECMWF are in relatively good agreement, showing the
front arriving Saturday night. As a result, have included chance
PoPs (30-50%) Saturday night into Sunday. Once the front departs,
cooler and less humid weather is expected early next week as highs
drop back into the middle to upper 80s by Monday.
Barnes
&&
.AVIATION... (For the 00z TAFs through 00z Tuesday Evening)
Issued at 624 PM CDT Mon Jun 17 2024
Scattered convection is fading as sunset approaches, but some
high-based ceilings will spread northward this evening with the
remnants. Some indications of lower ceilings near 5000 feet for a
time at KDEC/KCMI toward sunrise, before improvements take place
once again. For the most part, southerly winds will remain gusty
through the entire forecast period, 20-25 knots, but may subside
for a time tonight.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service North Platte NE
636 PM CDT Mon Jun 17 2024
.KEY MESSAGES...
- Thunderstorms this afternoon and into the overnight will lead
to an increasing threat for severe weather, with very large
hail, damaging wind, and isolated tornadoes.
- The redevelopment of heavy rainfall this evening and overnight across
north central Nebraska could lead to an increased threat of
flooding where heavy rains fell last night.
- ECMWF EFI values point to an unusually cool day relative to the
M- Climate on Wednesday. There is nearly a 30% chance that
high temperatures remain at or below 65F in North Platte.
&&
.SHORT TERM /THROUGH TUESDAY/...
Issued at 357 PM CDT Mon Jun 17 2024
Latest analysis from 20z shows that the warm front has been slow to
lift north, this is due to abundant stratus remaining across the
Sandhills and north central Nebraska. To the south, temperatures
have warmed into the lower 90s across far southwest Nebraska, but
still hang in the upper 70s and lower 80s along I80 in Lincoln
County. Looking regionally, very little developed cumulus is noted,
though there are signs of increased agitation across southeastern
Colorado and High County of the central Rockies. Overnight there
was an abundance of heavy precipitation across north central
Nebraska with widespread reports of 3" or greater from eastern
Cherry to Keya Paha County. The flood advisories that were out for
much of the day have been allowed to expire. A special thanks to
the NSSL group who gave us an early look at their 19z sounding. As
expected with the delayed burnoff of the stratus, the capping
inversion is quite strong near LBF.
Uncertainty is the word of the day with the CAMs very bearish on the
severe potential for later this afternoon and evening, though the
environment would suggest otherwise. Looking aloft, southwesterly
flow prevails, which is currently ushering increasing PVA as noted
by the developing CU over SE Colorado. Cyclogenesis has ensued over
the High Plains and subjectively now sits over far NE Colorado or
south of KOGA, near Grant. Southeasterly flow at the surface has
ushered TDs into the lower 70s as far north at KBBW and KLBF with
mid 60s as far west as the Highway 61 corridor. The warm front is
subjectively north of KLXN, but not as far as KBBW. Steep lapse
rates along the front are contributing to nearly 4k MLCAPE where
moisture is pooling just south of the boundary. HRRR soundings
reveal an uncapped solution, but we know that is not the case,
especially north where substantial CIN remains. That being said, we
believe with the increasing upper level support, isolated to
scattered severe storms will form eventually, which will be in the
vicinity of the lifting warm front and sfc low.
Once CI occurs, the environment will be very supportive of rotating
updrafts, which given the current situation, the Sandhills looks
prime, with the latest soundings indicating near pure streamwise
vorticity in the lowest few KMs of the hodograph. This is due to a
strengthening low level jet as evening progresses. With
southwesterly flow in the mid levels, hodographs will be quite long
which would point to all hazards with any supercell that develops,
though south of the boundary, large hail/wind will be the primary
concerns. As sunset occurs, increasing CIN would lead to elevated
storms with the concern being hail, wind, and heavy rainfall.
The storms should weaken as nightfall arrives, but if storms
maintain into north central Nebraska and/or eastern Cherry County,
will need to monitor for flooding as heavy rainfall occurred last
night. Lastly, mechanical mixing will allow for gusts of 40-45 mph
overnight south of the lifting front.
A cold front slides across the area tonight and tomorrow, but
remains a focus for storms Tuesday afternoon. At this point, most
of the activity will be east of the forecast area, but locations
along and east of a Frontier to Custer to Eastern Holt County could
see additional storms. Otherwise temperatures will be cooler in a
post frontal regime tomorrow afternoon with highs largely in the
70s.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Issued at 357 PM CDT Mon Jun 17 2024
A cold front is projected to be east of the area by the start of the
forecast period, though additional showers and storms are possible
as convection forms on a mid-level area of convergence. The area of
concern would be from Hayes County northeast through Custer, Wheeler
and eastern Holt Counties, though the heaviest QPF is expected to be
just outside of the forecast area.
A post frontal regime will usher in unseasonably cool temperatures
mid-week. The latest guidance suggest widespread 60s to lower 70s
across the entirety of the forecast area. Climatologically, highs
on Wednesday will run some 10-20 degrees below normal. The threat
for light showers continue, though continues to have highest chances
to the east.
Deeper low level moisture returns Wednesday night with easterly
upslope flow projected. WAA spreading from the west may aid in the
continuation of precipitation /thunderstorms/ well into Thursday
morning. The return of southerly flow late week and early next
weekend will keep the atmosphere unsettled with daily chances for
QPF, though late Saturday into Sunday, coverage looks less
promising. Severe weather, at least isolated coverage, would be
possible as the the pattern switches from southwesterly to
northwesterly aloft. Building heights from a central Rockies dome
of high pressure and decreasing cloud coverage would allow a return
to above normal temperatures early next week.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 635 PM CDT Mon Jun 17 2024
The main aviation concern will be thunderstorm development this
evening across southwest and north central Nebraska. While both
sites have the potential to see thunderstorms, the majority of the
storms will remain just to the west of both terminals. Any
thunderstorm that does develop could have large hail and damaging
winds. Drier conditions return for Tuesday with ceilings continuing
to rise. Strong sustained winds with gusts up to 30 knots will
continue through the overnight before gradually diminishing by
Tuesday afternoon.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Jacobs
LONG TERM...Jacobs
AVIATION...Kulik
Area Forecast Discussion
National Weather Service Memphis TN
912 PM CDT Mon Jun 17 2024
...New UPDATE...
.UPDATE...
Issued at 907 PM CDT Mon Jun 17 2024
Skies are mostly cloudy across eastern sections of the Mid-South
with mostly clear over the remainder of the region. Temperatures
this evening are mainly in the 70s. Showers and thunderstorms are
moving north across the eastern half of the region. This activity
is expected to show to a slow eastward shift over the next few
hours. With most areas already seeing rain cooled air, temperatures
should not change much through the overnight hours.
ARS
&&
.SYNOPSIS...
Issued at 340 PM CDT Mon Jun 17 2024
Shower and thunderstorm coverage will be much less on Tuesday as
upper level high pressure builds back west and into the Mid-South.
Hot and dry conditions will persist Wednesday through Sunday
as strong upper level high pressure remains over the region. High
temperatures will soar back into the mid to upper 90s each day.
Rain chances look to return early next week as high pressure
weakens over the Lower Mississippi Valley.
&&
.DISCUSSION...
(This evening through next Sunday)
Issued at 340 PM CDT Mon Jun 17 2024
A tropical-like day across the Mid-South at this hour. The latest
KNQA radar sweep reveals scattered to numerous showers and
thunderstorms along and west of the Mississippi River. The latest
SPC mesoanalysis reveals near record high PWAT values of 2.2
inches along the Mississippi River. Aloft, GOES-East Water Vapor
Imagery reveals a weak shortwave rotating clockwise around the
western periphery of the upper level ridge. Several strong storms
have occurred this morning and afternoon due to the combination
of moderate instability around 2000 J/kg of MLCAPE and up to 25
knots of bulk shear. Convective activity may hold on for several
hours after sunset as the main shortwave lifts out of the region.
A few additional strong storms are possible through sunset and an
instance or two of minor flooding is also possible.
Convective coverage will be much less on Tuesday, as the main
upper level ridge begins to retrograde back to the west. Showers
and thunderstorms will be mainly confined to areas along and north
of I-40 tomorrow morning and afternoon. Thereafter, the ridge of
high pressure will strengthen and become nearly centered over the
Lower Mississippi Valley. Temperatures will soar back into the
mid to upper 90s Wednesday through Saturday. With lower humidity
in place, heat indices should remain 100F or below.
Upper level high pressure looks to finally weaken over the region
late in the weekend. Showers and thunderstorms will likely return
as early as Sunday as weak troughing builds into the Lower
Mississippi Valley. Uncertainty amplifies early next week as
synoptic models are beginning to resolve a potential tropical
system in the western Gulf of Mexico.
AC3
&&
.AVIATION...
(00Z TAFS)
Issued at 642 PM CDT Mon Jun 17 2024
Primary short term concern in the scattered TSRA over northwest
MS, lifting north. Most recent runs of the HRRR depict the TS
potential falling off between 01Z and 02Z, with isolated -SHRA
continuing thereafter. This appears reasonable, given the loss of
daytime heating and weak deep layer shear. MEM surface winds will
take a while to recover from the considerable amount of convective
outflow, but should favor the SSE direction by late evening.
Quieter weather expected Tuesday. 12Z HREF Grand Ensemble depicts
TS potential well below 10 percent Tuesday afternoon.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
PUBLIC FORECAST...AC3
AVIATION...PWB
Area Forecast Discussion
National Weather Service Marquette MI
754 PM EDT Mon Jun 17 2024
.KEY MESSAGES...
- Scattered showers and thunderstorms tonight.
- Multiple rounds of showers and thunderstorms expected this
week. Strong to severe storms possible Tuesday night into Wednesday.
- Hot and humid Tuesday, followed by very muggy rest of the
week.
- Potential heavy rain event this weekend.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 159 PM EDT Mon Jun 17 2024
A line of showers and thunderstorms moved through Upper Michigan
today along of a warm frontal boundary, with what appeared to be a
mix of strong to severe storms embedded within the complex. As of
now, some pea sized hail has been reported and a wind gust at KIMT
measured 53 mph. Ahead of the line, dewpoints surged into the upper
60s to near 70F. Behind the line, temps in the 60s were observed
ahead of another line of showers draped northeast from northwest WI
and western Upper Michigan into western Lake Superior. At the time
of this writing, no lightning was being observed with this second
line. To the south, isolated thunderstorms are developing across
northeast WI within an environment characterized by 2000-2500 j/kg
MLCAPE, per SPC mesoanalysis just south of or along the warm frontal
boundary. Effective bulk shear from the same source generally ranges
from 40-50 kts.
As we progress through the remainder of the afternoon, ongoing
thunderstorms currently across the central will continue its
eastward progression. Additional shower and thunderstorm development
will be possible as the warm front begins lifting north. Main focus
area will be across central and eastern Upper Michigan given the
mean flow and proximity to the warm front as it continues lifting
north. There is some potential for strong to severe thunderstorms
within this, but the risk is low (<25%).
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 248 PM EDT Mon Jun 17 2024
The overall consensus of both ensemble and deterministic guidance
packages suggests the pattern across CONUS will continue to include
a stout mid-upper level ridge over the eastern third of CONUS while
deep and broad troughing holds fast over the western third. This
places Upper Michigan in a predominate south to southwest flow
regime and open to both Gulf of Mexico moisture and a warm/hot
airmass, and on the path for any shortwave, impulse, or MCS
developing across the Plains, at least until the weekend when a more
zonal pattern begins to emerge. In terms of sensible weather, Upper
Michigan can expect at least one hot day, multiple humid days,
multiple rounds of showers and thunderstorms, and flooding and
severe weather concerns in this forecast period.
Beginning this evening into tonight, showers and thunderstorms
should be ongoing initially thanks to surface low organizing and
beginning to lift north-northeast through the Central Plains.
Initially, showers/storms should be most prevalent across the
central/east but with the warm front lifting north, coverage should
shift north through the night. There is some potential for training
thunderstorms along the boundary. Severe weather threat should be
minimal this afternoon and overnight given the thoroughly worked
over environment, but some hail, stronger winds, and frequent
lightning can`t be completely ruled out. The main hazard will be the
rain, but it should be noted that the HRRR continues to back off on
some of the training risk. At this point, the WPC slight risk for
excessive rain seems reasonable given the training potential and
PWATS upwards of 2 inches, in addition to the 0.5"-2 inches of rain
estimated from today`s event. Through the night, the warm front will
lift north into Lake Superior/Ontario, which will allow rain to end
from south to north through the night. Overnight lows should only
dip into the 60s or upper 50s and some fog may develop, particularly
after the rain lifts north.
Tuesday looks to be mostly dry with Upper Michigan positioned
squarely within the low`s warm sector as it lifts into Minnesota.
With a slightly more dry airmass in place, effective mixing under
mainly high clouds or clear skies should support a hot, humid, and
breezy day. Daytime temps climbing into the 80s to low 90s is
expected while dewpoints approach 70F. This could support heat index
values in the low to mid 90s, with perhaps near 100F in downsloping
areas in the interior. Steep low level lapse rates should also be
able to mix down strong winds aloft. Current thinking is wind gusts
near 25 mph, but potential effective mixing may support winds
exceeding 30 mph in many locations in the afternoon, particularly in
downslope areas near Lake Superior. EFI continues to highlight this
unusually high wind potential with values of 0.6-0.8 across large
portions of the forecast area.
The low will lift into Ontario by Tuesday night while it pulls its
cold front through Upper Michigan. This will bring us another round
of showers and thunderstorms into Wednesday. There is some severe
thunderstorm potential, mainly across the west half Tuesday night,
but instability should be waning as they move into the area, so the
risk appears limited. However, the risk for heavy rain will return
as PWATS look to climb above 2 inches. The front should clear the
region by Wednesday afternoon/evening, with high pressure building
in after. There may be some daytime re-invigoration of the showers
and thunderstorms across the east half and south. Thursday looks to
be mostly dry as the pattern begins to shift into something more
zonal, but there is some uncertainty in where upstream impulses
will line up and how far east they`ll extend. This, while a couple
different shortwaves embedded within the near-zonal flow beings
across the Northern Plains and exiting out of the northern Rockies.
Another warm front will lift into the Upper Great Lakes Thursday
night/Friday, potentially supporting showers/storms by Thursday
afternoon. The boundary appears to stall out Friday over the Upper
Great Lakes as a surface low deepens and lifts out of the Central
Plains. The low will press through the region Saturday night and
Sunday while the shortwave aloft takes on a negative tilt. For a few
days now, guidance has been suggesting this setup, which could lead
to a potential heavy rain/flooding event in some areas in Upper
Michigan. Of course, this will be dependent on preceding rain, but
this system warrants monitoring.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 753 PM EDT Mon Jun 17 2024
With a warm front lifting n across the area tonight, some shra/tsra
will continue to be possible. Initially, SAW see ocnl -shra this
evening. Brief MVFR is possible, and not out of the question that
tsra could occur. Otherwise, there is about a 2-4hr period during
the night when IWD/CMX/SAW may be affected by tsra.
Coverage/location of tsra is uncertain, so only VCTS is included in
fcst for now. Later tonight, MVFR will likely develop at IWD, IFR at
CMX and IFR/LIFR at SAW where upslope sse winds will aid poor
conditions. LLWS also expected at IWD/CMX late tonight into Tue
morning. VFR returns to all terminals Tue morning with southerly
winds becoming gusty to 25-30kt by aftn.
&&
.MARINE...
Issued at 248 PM EDT Mon Jun 17 2024
Thunderstorm activity should be confined to eastern Lake Superior
this afternoon while showers will be possible mainly central and
east. In addition to this, mainly light synoptic winds will help fog
development, and its possible some that develops may be dense. Warm
front will lift north into the lake tonight and north of it by
Tuesday morning, supporting additional showers, possibly some
thunderstorms through morning. Some stronger storms should be
expected, but severe storms are not expected at this time.
South of the warm front on Tuesday, a strong low level jet will move
over Lake Superior ahead of a cold front moving eastward through
Minnesota. This low level jet will support southerly winds upwards
of 30kts across eastern Lake Superior, possibly some low end gales
for higher reporting platforms or where topography plays a local
influence on winds near the lakeshores between Marquette and
Whitefish Pt. Cold front will press through the lake Tuesday night
into Wednesday, potentially supporting another round of strong to
severe storms across western Lake Superior and thunderstorms and
showers lake-wide. High pressure appears to try to work in Thursday
but will be dependent on upstream systems. Another front moves into
the lake Friday/Saturday as a low pressure approaches from the west,
bringing with it another round of showers/storms. Current thinking
is for light winds in this system outside of thunderstorms.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JTP
LONG TERM...JTP
AVIATION...Rolfson
MARINE...JTP
Area Forecast Discussion
National Weather Service Pueblo CO
846 PM MDT Mon Jun 17 2024
.KEY MESSAGES...
- Critical fire weather conditions once again across the San
Luis Valley on Tuesday.
- Cooler and unsettled on Wednesday. Showers expected with
somewhat lower thunderstorm chances.
- Unsettled weather and warmer temperatures continue Thursday
onwards. Chances for storms vary each day, depending on
instability and shear.
&&
.UPDATE...
Issued at 843 PM MDT Mon Jun 17 2024
Quick update to the forecast database due to the expiration of
the Red Flag Warning for today. Red Flag Warning will remain in
effect for tomorrow for Fire Zone 224, the San Luis Valley.
Incorporated latest HRR and RUC model data as well as
observations.
&&
.SHORT TERM /THROUGH TUESDAY/...
Issued at 311 PM MDT Mon Jun 17 2024
Latest radar imagery depicting some isolated thunderstorm
development across the far eastern plains, mainly along and east
of a Lamar to Eads line. These storms are developing right
along the dry line, where upper 50s dew points and CAPE values
up 2000 j/kg are in place. Shear is not overly high but this
focus along with steeper lapse rates has supported a few robust
cells this afternoon. For the remainder of the afternoon, think
a couple more strong to marginally severe storms will be
possible right along the CO/KS border, before this development
shifts east. Given the high DCAPE, think winds up to around 60
mph will be possible with any strong/severe storm. Elsewhere
across the area, hot, dry, and windy conditions will continue to
support critical fire weather conditions through this evening
with no change to the current Red Flag Warning in effect.
Cold front arrives later tonight into early Tuesday morning,
providing some relief to the heat and increases in RH values
over most locations across southern Colorado. Did lower temps on
Tuesday but its possible they will need to be lowered more.
Fire danger lowers on Tuesday but with dry and windy conditions
still in place across the San Luis Valley, think critical fire
weather conditions will once again be likely. So, have issued a
Red Flag Warning for Tuesday. Precip chances are low on Tuesday,
but its possible there could be some isolated showers and
thunderstorms across the far southeast plains out ahead of the
front. If a storm were to develop, would not be out of the
question for there to be a strong to severe storm as well.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Issued at 311 PM MDT Mon Jun 17 2024
Wednesday-Thursday...
Post-frontal airmass lingering Tuesday evening into Wednesday will
set us up for a more active late-week, due to plentiful ambient
moisture and increased cloud cover. Looking aloft, an upper trough
will continue to deepen over the west coast while southwest flow
over our area continues in increase. High temperatures on Wednesday
will be much cooler than the previous several days, with mainly 70s
across our forecast area. Meanwhile, the breezy southwest flow aloft
will bring some orographic lift into our higher terrain, while
easterly upslope over the plains will help enhance precipitation
chances along the mountains/plains interface. Our severe chances
will be largely dependent on stability, which the cooler
temperatures and morning cloud cover may work against. Current
expectations are for showers to initiate over the higher terrain and
parts of the eastern plains, with a few rumbles of thunder, with
any thunderstorms that do form likely staying sub-severe.
Precipitation chances persist into Thursday as temperatures increase
into the high-80s, low-90s. This will give us some better
instability, though with mid-level flow weakening and becoming a bit
more disorganized, shear may be a limiting factor in thunderstorm
longevity. Regardless, showers and thunderstorms will be possible in
the afternoon hours, mainly over and near the higher terrain.
Friday Onwards...
As we move into late week and into the weekend, southwesterly flow
aloft will continue as some moisture from the Gulf is advected into
our area. As a result, shower and thunderstorm activity will
increase across both the mountains and plains through the rest of
this forecast period. High temperatures will increase, climbing back
into the 90s over most of the eastern plains. Additionally, an
embedded upper wave will be passing through the flow overhead,
leading to enhanced lift Friday afternoon and evening and higher
thunderstorm chances. Current model guidance shows CAPE near or
under 1000 J/kg with 30+ knots of bulk shear across the eastern
plains by evening. These wet and unsettled conditions will last
until close to the end of the weekend, when models hint at a new
upper-level ridge starting to build in over our region.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 522 PM MDT Mon Jun 17 2024
KCOS, KPUB, and KALS: VFR conditions are expected over the next 24
hours. Gusty winds this afternoon will lessen heading into the
evening, and remain relatively light overnight, with winds then
increasing again by late morning to early afternoon tomorrow.
Otherwise, dry conditions with mostly clear skies are anticipated,
with some mid to high clouds developing tomorrow afternoon.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon to 7 PM MDT Tuesday for COZ224.
&&
$$
UPDATE...MOORE
SHORT TERM...RODRIGUEZ
LONG TERM...GARBEROGLIO
AVIATION...SIMCOE
Area Forecast Discussion
National Weather Service Las Vegas NV
132 PM PDT Mon Jun 17 2024
.SYNOPSIS...A transient weather system will bring gusty conditions
and cooling temperatures to the region today and Tuesday, with
afternoon highs dropping below 100 for all but the lowest
elevations Tuesday afternoon. Thereafter, high pressure will
gradually rebuild with increasing potential for major heat impacts
by next weekend for much of the region.
&&
.DISCUSSION...Through next Monday.
Mostly clear skies over southern Nevada and the Mojave Desert as an
upper trough/shortwave moves through northern Nevada. Associated
cold front running from near Ely-Beatty-Lone Pine with gusty
northwest winds filling in behind the cold front. Meanwhile, pre-
frontal gusty southwest-west winds are continuing throughout far
southern Nevada, eastern California deserts and northwest Arizona.
Still expecting FROPA in the Las Vegas Valley between 8 pm and 10 pm
this evening.
Those gusty northerly winds will linger through at this Tuesday
morning before they begin to subside during the afternoon hours.
Cooler air filtering in behind the front will give the area a brief
reprieve from the hottest start to a June since 2013. Temperatures
quickly rebound back to normal Wednesday.
Finally, we have been monitoring smoke from the Post and Hesperia
Wildfires in southern California. Latest HRRR Smoke output suggests
much of the smoke/haze will affect southern San Bernardino and
Mohave Counties the rest of this afternoon and tonight. If both
fires remain active the HRRR suggests more favorable trajectory for
smoke/haze to work back toward southern Arizona Tuesday.
For the long term we are monitoring the influx of `monsoon` moisture
into at least Arizona by weeks end and the return of `hot`
temperatures areawide. An inverted trough over the western Gulf of
Mexico, in the Bay of Campeche is progged to move west across
mainland Mexico reaching the eastern Pacific/Sea of Cortez Friday.
Lower level moisture progged to reach eastern Arizona Thursday and
continue west toward Mohave County Friday. Some guidance suggests
potential for a secondary influx from a gulf surge advecting
moisture up the lower Colorado River over the weekend. This will
need to be closely watched this week but for now NBM does have a
slight chance of thunderstorms over the higher terrain of eastern
Mohave County each day Friday-Monday.
Building heights under the subtropical ridge will lead to another
period of well above normal temperatures with highs approaching 110
degrees on Saturday. Highs at or greater than 110 degrees are in the
forecast Sunday through Tuesday. Las Vegas probabilities of 110
degrees or higher are at 50% or greater Saturday through next
Thursday. As such, expect widespread `Moderate` HeatRisk, while some
desert valleys return to `Major` HeatRisk on Saturday and beyond.
Excessive Heat products may be needed.
&&
.AVIATION...For Harry Reid...Gusty southwesterly winds will
continue through the afternoon hours with gusts to around 25 knots.
A cold front will move through the area this evening, causing winds
to shift to the northwest with gusts over 20 knots possible after
about 03Z. Wind will begin to diminish during the early morning
hours and become lighter around 10kt from the northeast Tuesday
afternoon periods of FEW to SCT high clouds will pass over the area
through the TAF period.
For the rest of southern Nevada, northwest Arizona and southeast
California... Gusty southerly to southwesterly winds continue this
afternoon in the Las Vegas Valley and Colorado River Valley. Winds
at these locations will shift to the north to northwest this evening
with the passage of a weak front. Gusts accompany the frontal
passage but should subside later in the night. At KDAG, winds remain
gusty out of the west through the evening. Elevated smoke from
wildfires in southern California may spread over KDAG but should
have minimal impact on aviation. In the Owens Valley including KBIH,
winds maintain a northerly direction with an increase in gusts in
through the evening then decreasing overnight. FEW-SCT high clouds
will pass over much of the forecast area through Tuesday morning.
&&
.FIRE WEATHER...Very dry conditions will persist today with
minimum relative humidity dropping below 15% for most areas this
afternoon and evening. A Red Flag Warning remains in effect for
AZZ101-102 today due to the very dry conditions and persistent gusty
winds resulting in high fire start and spread risk. Sustained winds
in northwest Arizona will likely exceed 20 mph for much of the day.
Elsewhere, it will be dry but winds will struggle to jump to
impactful levels for an extended period of time and fuels remain
marginal. NVZ460 could reach Red Flag Warning criteria briefly this
evening and early overnight; however, due to the short-lived threat
held off on the issuance.
&&
.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&
$$
DISCUSSION...Pierce
FIRE WX...Outler
AVIATION...Berc
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