Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/30/22
Area Forecast Discussion
National Weather Service Binghamton NY
1035 PM EDT Mon Aug 29 2022
.SYNOPSIS...
Warn and humid conditions are expected to continue on Tuesday,
along with showers and thunderstorms, especially during the
afternoon. A few storms could be strong to severe with gusty
winds and locally heavy rain. Cooler and drier conditions are
then expected for much of the remainder of the week.
&&
.NEAR TERM /THROUGH TUESDAY NIGHT/...
1030 PM Update:
Made some minor adjustments to PoPs to account for a few
additional scattered showers and thunderstorms working its way
into the Twin Tiers from Central PA. Expecting these to
gradually dissipate later tonight. Otherwise, the previous
forecast remains on track.
630 PM update...
The line of storms mentioned in the previous forecast have
over-performed and the CAMs struggled with it. Storms are
starting to weaken but the southern portion of the line moving
through the Southern Tier still looks good. With this line of
storms, there has been strong wind gusts and multiple reports of
trees and wires down. Again, it does look like these storms are
weakening though as the sun begins to set and the environment
slowly becomes more stable. PoPs were increased for this line
with mostly manual adjustments. These storms have cooled the
areas that they have passed through. Upper 60s and low 70s are
being reported west of this line while 80s and 90s are still be
reported to the east. Temperatures were touched up due to this
storm.
345 PM update...
A line of showers and thunderstorms continue to move through western
NY and PA. The CAMs have not been handling this system well at all
though the latest HRRR may now be getting it. Even so, this system
will move through the region late this afternoon and into the
evening hours. SPC mesoanalysis shows that there is decent
instability present across northern NY with CAPE of at least 1500
J/kg and bulk shear around 20 kts. Gusty winds would be the main
threat with this line as DCAPE is already over 1000 ahead of this
line. While there is dry air present that could break up this line
over our region, isolated to scattered thunderstorms will be
possible over portions of the CNY, specifically from the western
Twin Tiers and all the way up through the Tug Hill Plateau. This
line should dissipate after sunset, if not before, once the
environment becomes more stable. Conditions would then be mostly dry
through the overnight hours. Overnight temperatures will be warm,
only falling into the upper 60s to low 70s. If skies clear enough
tonight, there may also be some patchy valley fog in the Wyoming
Valley and Catskills.
There remains some uncertainty on what happens tomorrow. An upper-
level trough sweeps across the Great Lakes Region and into the
Northeast tomorrow. A weak wave or two could pass through the
region, triggering some rain showers in the morning across most of
CNY. If this occurs, then the concern for the severe threat during
the afternoon would decrease. However, if conditions can remain dry
through the morning and skies are just partly cloudy, then daytime
heating will help create a more unstable environment for the main
line of showers and storms ahead of a cold front. Modeled CAPE will
be 500 to 1000 J/kg with shear up to 35 kts. Strong wind gusts will
be the main threat, though heavy rainfall will also be possible.
PWAT values will be around 2 inches and elevated warm cloud depths
are also expected. Forecasted QPF totals from tonight through
Tuesday night range form 0.5 to 1.5 inches with up to 2 inches
locally. This could lead to ponding and even isolated flash flood
issues, especially in urban and poor drainage areas.
Tuesday is expected to be hot and humid as well. Highs will be in
the 80s for most with dewpoints in the 60s and low 70s. Heat indices
are not expected to be as high as they were today but valley
locations from the Twin Tiers and southward could have values in the
low 90s. The high temperatures will be reached earlier in the day
for portions of CNY as the showers and storms move in. For areas
that had likely PoPs (at least 55%) or higher, than the highs were
reduced a few degrees from NBM and Conshort blended guidance. For
the rest of the region, they were reduced just a degree.
The main line of showers and storms is expected to be east of I-81
by Tuesday evening as it continues to move through the region with
the cold front lagging behind it. Conditions should become dry from
the west during the overnight hours. By early Wednesday morning, the
cold front pushes the showers and storms out of the region and
brings drier, cooler air into the region. With skies clearing, winds
becoming calmer, and the added moisture from the rain showers,
patchy valley becomes possible after midnight. Temperatures are
expected to fall into the upper 50s and low 60s.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
305 PM Update
Most of the northeastern U.S. will remain under a negatively
tilted upper level trough at the start of the period, as it
slowly lifts to the northeast over time. Precip coverage will
taper off by Wednesday morning, but additional showers will be
possible later in the day as several weaker shortwave troughs
rotate through in the afternoon, aided by a 100+ knot jet streak
nosing into NY/PA. Northwest flow will continue on Thursday,
and there`s an outside chance of some lake-enhanced showers near
and north of the Thruway. High pressure will build in on
Thursday night, along with drier air and lighter winds. Low
temperatures on Friday morning could even dip into the 40s.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
305 PM Update...
After a crisp start Friday morning, temperatures will rebound to
near seasonal highs on Friday, as high pressure begins drifting
offshore. Temperatures will trend back up above normal on
Saturday as a cold front slowly approaches the lower Great
Lakes. This front will be the next chance for rain, though it
looks like it would likely hold off until Sunday, but
potentially sagging across the area and becoming nearly
stationary thereafter.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
VFR conditions are expected through the first half of this
period. There is still a line of showers/storms that is moving
east across the NY terminals. The storms have begun to weaken
though and should just be rain showers by the time it gets to
RME. Gusty winds have been common with this system though
restrictions have not always occurred. Once this line moves
through, dry conditions are expected overnight. Low-level wind
shear (LLWS) is expected at RME, SYR, BGM and ELM tonight and
into early Tuesday morning. Winds also become calmer with
sustained speeds of 5 to 10 kts.
A fairly strong system is expected to bring multiple periods of
showers and thunderstorms Tuesday afternoon. With this system
ceilings will fall to MVFR or below and visibilities will be
reduced, especially if a thunderstorm passes right over a
terminal. Heavy rainfall and strong wind gusts will be the main
hazards with any storm. There remains some uncertainty with the
this system, especially with the timing of this system and how
low restrictions may fall. Most model guidance keeps showers and
storms around in the region just past this TAF period. Outside
of these thunderstorms, winds will be from the southwest with
gusts of 15 to 20 kts.
Outlook...
Tuesday night...Occasional restrictions anticipated in showers
and thunderstorms as the system moves out. Low clouds and patch
fog will be possible once the rain moves out.
Wednesday through Thursday...Mainly VFR; low chance for showers
and associated restrictions at SYR and RME.
Friday though Saturday...Mainly VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.
&&
$$
SYNOPSIS...BJG/BTL/MDP
NEAR TERM...BJG/BTL
SHORT TERM...MPH
LONG TERM...MPH
AVIATION...BTL
Area Forecast Discussion
National Weather Service Dodge City KS
517 PM CDT Mon Aug 29 2022
...UPDATE TO AVIATION...
.SHORT TERM...(This evening through Tuesday)
Issued at 316 PM CDT Mon Aug 29 2022
This afternoon`s water vapor loop and RAP analysis showed a mid
level trough moving east across the Northern Plains into the Great
Lakes region, which was responsible for pushing a weak cold front
south across Kansas. Late this afternoon, surface observation plot
and clear-air radar returns showed a weak low pressure area at the
surface centered near Dodge City. There were a couple areas of
enhanced boundary layer convergence in vicinity of this low and the
cold front, and any of these enhanced areas of convergence may be
enough to initiate surface-based convection. The best signal among
the CAMs, including the latest several HRRR runs, suggests the
region from Dodge city up toward La Crosse would be the best area
for initiation, and the north-northwest flow aloft would put the
areas south of Dodge City to La Crosse line in the greatest threat
area for convection.
Mid level winds around 6km AGL will increase slightly through the
evening, so any storms at or shortly after sunset could be
marginally severe owing to slightly increased deep layer shear
supporting a multi-cell cluster or two. The overall lack of
substantial forcing for ascent should keep convective activity
fairly isolated/widely scattered in nature. After sunset, there is
some indication that pristine convection may develop along the
elevated front centered around 850-800mb or so, a bit farther north
up along I-70, however the latest POP grids will not necessarily
reflect this later in the evening/late night hours, but it is
something that will need to be monitored.
Thunderstorm chances will trend downward fairly significantly early
Tuesday morning as the cold front continues to move south across
southwest and eventually through south central Kansas. On Tuesday,
temperatures will pull back some 5 to 8 degrees from this
afternoon`s highs on the northeast surface winds behind the front
with any new convection on Tuesday expected to be well to the south
across West Texas.
.LONG TERM...(Tuesday night through Monday)
Issued at 316 PM CDT Mon Aug 29 2022
Quiet weather will prevail for much, if not all the Long Term period
through the upcoming weekend. The one exception to this may be
Friday/Friday Night when another polar front will likely push south
into western Kansas as another shortwave trough moves along the
Canadian border into the Upper Great Lakes region. The latest ECMWF,
GFS, and GDPS models do show some QPF signal, although since these
are apparently new trends in the global models for the end of the
week, the NBM POPs are still fairly low in the 10 to 15 percent
range. As far as temperatures goes, persistence will be a pretty
good forecast method through much of the period as there will not be
much change in the lower troposphere thermodynamic regime --
resulting in highs lower to mid 90s and lows generally lower to mid
60s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 513 PM CDT Mon Aug 29 2022
Isolated to widely scattered thunderstorms will persist across portions
of central and southwest Kansas through this evening, likely affecting
the vicinity of KDDC and possibly KHYS and KLBL. Storms are expected
to begin dissipating after sunset. Otherwise, predominantly VFR conditions
will prevail through Tuesday afternoon. Gusty south winds will persist
across south central Kansas and portions of southwest Kansas through
mid-evening as a near stationary frontal boundary remains anchored from
southwest Kansas northeast into north central Kansas. Northeast winds
around 10 to 20kt are expected to continue north of the boundary in
west central, central, and extreme southwest Kansas. Widespread light
and variable winds are expected later overnight with the loss of daytime
heating.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 93 62 94 / 20 0 0 0
GCK 62 92 61 93 / 20 0 0 0
EHA 62 90 61 92 / 10 10 0 0
LBL 64 92 62 93 / 20 10 0 0
HYS 62 91 62 94 / 10 0 0 0
P28 67 93 63 94 / 30 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Umscheid
AVIATION...JJohnson
Area Forecast Discussion
National Weather Service Quad Cities IA IL
641 PM CDT Mon Aug 29 2022
...00Z AVIATION UPDATE...
.SYNOPSIS...
Issued at 204 PM CDT Mon Aug 29 2022
An active day was seen through much of the area today, as a slow
moving cold front fired up some strong to severe storms throughout
the area. The line of storms produced very frequent lightning and
heavy rainfall. Some large hail was seen as well. These storms have
since moved out and temperatures are slowly starting to rebound up
closer to the Interstate 80 corridor. In the south, they have stayed
relatively dry and clear all day, which has allowed them to increase
into the upper 80s to 90s. Areas south of Interstate 80 will need to
be watched through the remainder of the afternoon and evening, as
severe weather potential exists. The SPC has these areas highlighted
in a Slight Risk for severe weather, with primary hazards being
damaging winds and isolated large hail.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 204 PM CDT Mon Aug 29 2022
Remaining showers/storms along the cold front may be seen along and
south of the Highway 34 corridor. Confidence is not very high on
this, as short term guidance does not have a good grasp on where
these will set up. Along those same lines, some of the latest runs
of the HRRR try to initiate convection again between the Interstate
80 and Highway 34 corridor. With that said, we are not placing our
faith in the short term guidance. They have performed poorly on this
event thus far. If we do get storms, they hold potential to go
strong/severe fast, with severe winds and hail being the main
hazards.
Cold front slowly continues to push out of the area this evening and
will be out of the area by nightfall. While we may see some post
frontal showers and storms in our far south and southeast, most of
the area will be dry. Beautiful post-frontal air will settle in and
the clouds will move out. Thus, temperatures and humidity drop
significantly compared to the prior night, where much of the area
will be in the upper 50s to near 60. With a lower humidity, it will
feel quite cool. Open those windows!
Tomorrow, you cannot ask for a better summer day. High pressure
moves in and we will sit with clear skies and a northwest breeze.
Temperatures will be in the upper 70s and low 80s, with low
humidity. Enjoy a beautiful Tuesday.
.LONG TERM...(Tuesday night through Monday)
Issued at 204 PM CDT Mon Aug 29 2022
Key Message:
1) Seasonable weather will be seen through midweek, as high pressure
settles in and we remain in northwest flow.
Discussion...
Relatively quiet stretch of weather ahead of us. High pressure moves
in midweek, which will leave us with quiet and seasonal weather.
Both aloft and near the surface, we will remain in northwest flow.
While there are some weaker waves that pass nearby, we do not get
any return flow until late week and into the weekend. Once we see
the return flow, long term guidance hints at the potential for some
precipitation chances on Friday/Saturday, associated with another
passing wave. This would seem to be the next chance of any
precipitation, but there is not much agreement on this. Thus, we
opted to keep the Slight PoPs unchanged Friday into Saturday. Enjoy
a beautiful week in the 80s, with low humidity.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 637 PM CDT Mon Aug 29 2022
A few showers will remain possible early evening at MLI and BRL until
a mid level front passes. Coverage looks to be fairly isolated
and thus no mention at either terminal, but will monitor and amend if
needed. Otherwise, VFR conditions are expected through the period
with westerly winds at or below 10 kts tonight become gusty N/NW at
15-25 kts after 15z Tuesday.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...Gunkel
SHORT TERM...Gunkel
LONG TERM...Gunkel
AVIATION...McClure
Area Forecast Discussion
National Weather Service Grand Junction CO
544 PM MDT Mon Aug 29 2022
.SHORT TERM...(Tonight through Tuesday night)
Issued at 210 PM MDT Mon Aug 29 2022
GOES visible satellite imagery reveals mostly sunny skies across
the Western Slope this afternoon. This is in response to building
high pressure across the Great Basin with dry northerly mid-level
flow on its eastern flank. Diabatic heating, orographics and left
over moisture have resulted in some high based cumulus clouds over
parts of the higher terrain, particularly the San Juans and
Continental Divide mountains, but that`s about it. RAP mesoscale
analysis is depicting roughly 250-500 j/kg of surface based CAPE
across the San Juans so a brief and spotty shower can`t be
completely ruled out there. However, short range forecast
soundings indicate a robust mid-level cap is in place so that will
greatly limit the overall convective potential. Otherwise, it`s a
quiet weather day for most with temperatures ranging 5 to 10
degrees above normal.
Clear skies and light winds will make for pleasant weather again
tonight. Low temperatures this morning were several degrees below
blended guidance so knocked tonight`s lows down several degrees
given continued ideal radiational cooling conditions. Tuesday is
shaping up to be a similar day to today with high pressure
remaining in control. A couple isolated showers and perhaps a
brief t-storm are possible again across the San Juans, but even
there, most of the day will be rain free. High temperatures will
climb a couple more degrees on top of today`s readings and will
remain well above average for the end of August.
Cool and quiet weather is in store Tuesday night under mainly
clear skies.
.LONG TERM...(Wednesday through Monday)
Issued at 210 PM MDT Mon Aug 29 2022
Ensemble guidance continues to advertise a highly anomalous ridge
of high pressure dominating the western U.S. through the entire
long term forecast. A few low amplitude waves moving through fast
west and northwesterly flow may attempt to flatten the ridge
somewhat Wednesday and Thursday, but 500mb heights are progged to
quickly recover and strengthen soon after the waves exit stage
right. In fact, by Friday and Saturday, the ECMWF ensemble
situational awareness table shows 500mb heights across the Great
Basin, northern Four Corners and northern Rockies/Intermountain
West climbing above the >99th percentile. Given a ridge of this
magnitude at this time of year, a period of anomalous late season
heat is becoming increasingly likely to close out August and start
September. The latest deterministic NBM is already spitting out
high temperatures across the Grand Valley, Utah Grand Flat and the
lower desert valleys of southeast Utah in the upper 90s and low
100s for the latter half of the week and weekend. Compared to
climatology, these forecast high temperatures are roughly 10 to 15
degrees above normal. In the climate record for the Grand
Junction area, there are only 2 more days left this year when the
daily record high temperature is in the triple digits and both are
in the first week of September (9/1: 100F in 2019 and 9/4: 100F
in 1995). Thus, temperatures that hot this late in the summer are
rare. Given Labor Day weekend is coming up and many will be
recreating outdoors, it`s important to start getting the message
out now. Don`t let late season heat sneak up on you and keep the
heat in mind when making outdoor plans later this week and this
weekend.
As far as precipitation chances, any shower and thunderstorm
activity is likely to be confined to the San Juans and portions of
the central Continental Divide mountains each afternoon with
mainly dry weather expected elsewhere. Moisture is likely to be
limited with the tap of subtropical moisture displaced far away
from our forecast area. In a hot and dry pattern like this one,
the threat shifts away from heavy rain and flash flooding to gusty
outflow winds. Not to say a few stronger cells can`t cause
localized flooding issues, but the risk is much lower than
compared to the last few weeks and months. Some ensemble guidance
is hinting at more robust moisture making a return sometime next
week so that risk may very well increase again. Since we`re still
a week or more away from that potential, however, we`ll late
guidance sort that out as we get closer.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 542 PM MDT Mon Aug 29 2022
Expect VFR conditions for the next 24 hours under mostly clear skies
and generally light terrain driven diurnal winds. There is a slight
chance for isolated showers and thunderstorms after 18Z mostly along
the Continental Divide in central and southern Colorado.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...None.
UT...None.
&&
$$
SHORT TERM...MDM
LONG TERM...MDM
AVIATION...DB
Area Forecast Discussion
National Weather Service Indianapolis IN
1123 PM EDT Mon Aug 29 2022
...Updated Aviation Discussion...
.Forecast Update...
Issued at 931 PM EDT Mon Aug 29 2022
Surface analysis this evening shows a trough of low pressure
stretching from Lake Michigan across IL to eastern MO. GOES16 shows
many areas of convection ahead of this trough stretching from the
eastern Great Lakes across Indiana to southern MO and the southern
plains. Water vapor showed a plume of moisture in place across
Central Indiana, ahead of the upper trough in place over the upper
midwest. A warm and humid air mass remained in place across Central
Indiana with dew points lingering near 70. Radar shows scattered
convection across the area. Some storms to the east were remnants
from early daytime heating storms while newer development to the
west was associated with the approaching upper trough.
HRRR continues to suggest that scattered convection along and ahead
of the approaching surface trough will continue to push across
Central Indiana overnight. Forecast soundings overnight remain
rather saturation, with dry air arriving only late in the night from
the northwest in the wake of the passing trough axis. Thus expect
the ongoing scattered showers and storms to continue to make
progress across Central Indiana overnight. SPC mesoanalysis page
suggests some CIN in place across the area and the severe threat
appears to be limited, but heavy rain and frequent lightning will
still be expected with any storms. Thus have used high pops
overnight, particularly in the 10pm - 3am window as best forcing
should pass during that period. As dry air arrives late tonight,
ramping pops lower from NW toward the SE. Minimal temperature
advection is expected overnight, thus lows around 70 appear on the
mark and only minor adjustments were made for that.
&&
.Short Term...(This evening through Tuesday night)
Issued at 250 PM EDT Mon Aug 29 2022
Highlights:
-2 rounds of strong to severe storms, first round this afternoon
north of Indy, second late this evening across central Indiana.
-Damaging winds primary threat, especially towards Lafayette.
This Afternoon and Tonight.
This discussion will mostly be focused on the larger scale pattern
for the storm potential this evening. For finer scale details, see
Meso-discussion above.
A seasonably strong upper level trough continues to slowly push to
the east across the Upper Great Lakes Region with a 250mb jet
approaching 100kts. This strong jet combined with CAPE values well
over 3500 J/kg have allowed for storms to initiate across northern
Illinois. This complex will be the first potential for strong to
severe thunderstorms across central Indiana as it pushes to the east
and south. Further to the south, isolated to scattered showers have
formed north of the Ohio River where a remnant frontal boundary
along an axis of convergent air in the mid levels is creating an
environment favorable for these weak and scattered showers.
Going into later this afternoon expect that the first complex may
skirt the northern counties as the cold pool strengthens and the
complex begins a southern turn. As these storms move south they will
be exiting the area of highest instability and moving into a weakly
sheared environment which will lead to a gradual weakening but will
depend on the strength of the cold pool. A second round of storms
is then expected to initiate late this evening and move into central
Indiana during the early overnight hours. Confidence in the
strength and southern extent of the complex remains low with a lot
of uncertainty as to how much time for recovery there will be
across northern Illinois. Do think that the area near Lafayette
remains where the highest potential for damaging wind gusts will be.
The severe threat will lessen later into the overnight hours as the
loss of heating combined with weaker shear will limit the
maintenance potential for any storm complex. Do think that periods
of heavy rain and perhaps training of showers and storms may
continue well into the night causing isolated flooding problems.
Rain chances will then come to an end by sunrise as the moisture
transfer becomes cut off by the advancing trough. Can`t rule out
some patchy fog towards daybreak with the abundant moisture, but the
lack of clearing and winds around 5-10 mph will limit fog coverage.
Tomorrow and Tomorrow Night.
The aftermath of the system tonight will bring a return to dry and
pleasant conditions across central Indiana. Surface high pressure
will quickly build in across the area during the afternoon hours
with CAA aloft in the presence of northwesterly flow. Dew points
will crash into the low to mid 50s by mid afternoon which will then
allow for cooler temperatures tomorrow night.
&&
.Long Term...(Wednesday through Monday)
Issued at 250 PM EDT Mon Aug 29 2022
Upper troughing across the northeast with upper ridging out west
will result in predominantly NW flow through the long term period.
At the surface, high pressure is likely to dominate until the
weekend, providing pleasant weather with large scale subsidence
dropping dewpoints into the low 50s. Look for an upper shortwave to
approach the area late week. Precipitation is unlikely with surface
high pressure keeping the low levels dry, but an increase in cloud
cover is expected.
By the weekend, temperatures will warm up as upper ridging builds
across the region. In addition, winds should become more southerly
with the surface high moving east of the area Friday. Increasing
moisture due to southerly flow and daytime heating may lead to a few
pop up showers and storms, but confidence is very low this far out.
Ensemble guidance show an inverted trough across the southeast
moving north closer to southern portions of the CWA around Sunday.
If the trough can make it far enough north then rain chances will
need to be slightly increased. Confidence in this scenario is low at
this time as most ensembles keep it south of central Indiana.
Expect below average temperatures to begin the period. Southerly
flow and a building upper ridge should allow temperatures to climb
into the upper 80s by the weekend.
&&
.Aviation...(06Z TAF Issuance)
Issued at 1123 PM EDT Mon Aug 29 2022
Impacts:
* Convection with brief MVFR/IFR conditions will be expected for the
first 3-4 hours of the Taf period.
* VFR Conditions will be expected for much of the TAF period after
10Z-12Z.
Discussion:
Ongoing convection was found across much of Central
Indiana...impacting LAF...IND...HUF. This is associated with the
approaching upper wave and cool front arriving from the west.
Convection is expected to continue and progress eastward over the
next 3-4 hours. HRRR shows precip exiting the area by 10Z as
forecast soundings show the arrival of dry air within the mid levels
as the convection departs.
VFR conditions are expected thereafter as NW flow and subsidence
will persist in advance of the arrival of high pressure over the
plains states. Forecast soundings show a dry column on Tuesday with
unreachable convective temps. Thus a mostly sunny sky will be
expected at that time.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Update...Puma
Short Term...White/Melo
Long Term...Melo
Aviation...Puma
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1108 PM EDT Mon Aug 29 2022
.UPDATE...
Issued at 1108 PM EDT MON AUG 29 2022
The forecast remains largely on track. A swath of showers and some
embedded lightning hang across the far northern counties,
otherwise it`s quiet elsewhere for now. Have fine tuned PoPs and
sky based on the latest trends, while also loading and blending
the latest T, Td, and wind obs. Grids have been sent to NDFD and
Webfarms.
UPDATE Issued at 902 PM EDT MON AUG 29 2022
Plenty of CAPE from the warm and humid airmass this afternoon has
allowed for scattered showers and thunderstorms to develop early
this evening. Fortunately, with the loss daytime heating and
suggested CAM trends, activity will taper off for most over the
next couple of hours. With that said and given the radar trends,
did bump up PoPs to include slight chance (20%) in the southeast
during this timeframe. Anticipate a bit of a lull as we near
midnight, before the approaching upper level trough and cold front
bring the return for showers and thunderstorms late overnight and
into Tuesday morning. Have updated sky grids to better reflect
satellite trends, as well as blending in the latest T/Td obs.
&&
.SHORT TERM...(This evening through Tuesday night)
Issued at 333 PM EDT MON AUG 29 2022
Showers and thunderstorms have developed this afternoon on what
appeared to be a pre-frontal trough axis. These storms have been
moving through mainly areas around the I-64 corridor. Overall the
CAMs have struggled to handle this convection, with the later runs
of the HRRR starting to show more promise. A cold front remains
NW of the area right now and will push toward eastern Kentucky
later tonight into Tuesday. This will bring better chances of
showers and thunderstorms toward dawn on Tuesday morning, as help
from a weak wave is noted in the mid-levels. Overnight lows will
generally be around 70 degrees in most spots, with increasing
cloud cover expected through the night.
Tuesday chances of showers and thunderstorms increase from west
to east through the day. This as a cold front nears and an upper
level wave noted in the Upper Midwest becomes slightly deeper
across the Ohio Valley bringing decent height falls with it. This
will lead to a good shot of rainfall to the area with some seeing
0.5 to possibly an inch of rainfall. While the moisture is ample
for this time of year the progressive nature of this system would
lead to little if any flooding potential. Afternoon high
temperatures will remain in the lower 80s for most spots under
mostly cloud skies.
Tuesday night, the main cold front will push southeast through the
area and northwest winds will become the theme. Overall flow will
be weak as high pressure noses eastward and could allow for a few
ridge/valley splits. However, opted not to go too wild with the
splits given the front and northwest flow potential keeping this
from being as much a factor. The other issue could be some decent
fog production in the valleys given previous day rainfall and
cooler are advecting into the area. Most locations will be in the
lower 60s with some mid to upper 50s possible in the valleys.
.LONG TERM...(Wednesday through Monday)
Issued at 339 PM EDT MON AUG 29 2022
The last day of meteorological summer will segue into autumn with
an absolutely gorgeous stretch of warm, dry warm sunshine-filled
days and refreshingly cool nights. Humidity levels, above normal
temperatures and some rain chances do return for the Labor Day
weekend, but it doesn’t look like a washout.
The latest model suite analysis beginning 12z Wednesday shows the
5H trough axis well to our east while heights rise over the Ohio
Valley to the east of a sprawling ~596 dam high centered over
Utah. The sinking motions aloft due to the closed high will
manifest as a sprawling ~1019 mb surface high pressure centered
near/over Missouri. For the first couple of days of the long-term,
several pieces of shortwave energy will ride through the top of
the ridge. A more pronounced shortwave will pass from the Alaska
Panhandle to the the northern Saskatchewan on Thursday where it
will deepen into a sub 990 mb low. The vigorous surface low will
then race toward northern Quebec by Saturday while pulling arctic
air southward behind the system’s cold front. The aforementioned
surface high pressure lazily drifts over the Ohio Valley on
Thursday and across Upstate New York/New England on Friday. Behind
this high, we will see the aforementioned cold front sweeping
southeastward into the Upper Midwest/Upper Great Lakes on Friday
before quickly slowing thereafter due to fading upper level
support. Much of the guidance suggests that this decaying
boundary continues to sag southward, eventually settling to near
the Ohio River by week’s end. PWATs will recover back above 1.5
inches by Saturday, sufficient for some deep convection, but the
lack of notable forcing should keep coverage limited.
Breaking down the period in more sensible terms, expect mostly
sunny and warm afternoons on Wednesday and Thursday with
temperatures peaking in the lower to middle 80s. A moderate ridge-
valley split should develop each night. Lows are forecast to range
in the 50s at all locations on Wednesday night and in the mid 50s
to lower 60s on Thursday night. Humidity levels rise and small
rain chances return over the weekend, but there will still be
plenty of dry time. Highs in the mid to upper 80s can be expected
from Friday on through Labor Day while nighttime temperatures
settle back into the 60s. Valley fog is expected to form in the
favored valley locales each night.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 902 PM EDT MON AUG 29 2022
Scattered showers and thunderstorms could impact SYM and SJS for
the first couple of hours of the period. These could reduce
categories to IFR briefly, before all sites improve to VFR late
this evening. An approaching disturbance will then bring renewed
showers and storms toward dawn, reducing ceilings for all to
MVFR, or lower, through mid to late morning as well as periodical visibility
drops. Improvement to VFR will then return from NW to SE through
the day. Winds will generally remain below 10 kts, with the
exception being any storms passing near or over terminals.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BB
SHORT TERM...DJ
LONG TERM...GEERTSON
AVIATION...BB
Area Forecast Discussion
National Weather Service Memphis TN
733 PM CDT Mon Aug 29 2022
.UPDATE...
Diurnal convection continues across portions of northeast MS and
West TN this evening but remains loosely organized at best.
Instability is still strong with MLCAPE on the order of 2500 J/kg
and is uncapped across most of the area. This activity will likely
wane over the next few hours, but may not dissipate altogether
like previous nights. Looking upstream across northern AR and
southeast MO, more organized convection is moving south ahead of a
prefrontal trough that will dip into the area overnight.
Latest CAM guidance shows this convection holding together as it
moves southeast into the CWA over the next several hours, holding
together until reaching I-40. RAP progs indicate effective bulk
shear increasing to 20-25 kts, giving this cluster of storms a
little boost while large-scale forcing for ascent will increase
this evening downstream of an approaching shortwave trough. The
severe weather threat will remain low, but a strong storm or two
cannot be ruled out with gusty winds and/or small hail. Of greater
concern is the potential for locally heavy rainfall. Precipitable
water near 2.2" and a high melting level suggest the potential for
efficient rainfall producing storms with a potential for
training. The 12z HREF localized probability max mean shows a
decent coverage of 1-2" rainfall amounts with localized higher
totals, mainly north of I-40. PoPs and sky cover were increased
for the first period.
MJ
&&
.PREV DISCUSSION... /issued 317 PM CDT Mon Aug 29 2022/
DISCUSSION...
Currently...A weak mid level trough extends from the OH Valley
into northern Arkansas. Weak low level convergence is triggering
scattered scattered showers and thunderstorms across West TN and
N MS. Outflows from this activity are generating additional
development that can be seen nicely on the KNQA 88D across the
Memphis metro. Very high dewpoints combined with temps around 90
is producing heat index values of 100 to 105 degrees across the
Mid-South.
Tonight through Tuesday...This mainly diurnally driven convection
will gradually dissipate with loss of heating early this evening.
A very unstable airmass, PWs greater than 2 inches and slow
movement could result in some isolated heavy rainfall amounts and
localized flooding. A more potent mid level trough will move into
the Great Lakes tonight and drive a cold front south. This front
will push through the Mid-South on Tuesday. Showers and
thunderstorms developing in advance of the front, over the I-44
corridor, will probably move into northern areas of the Mid-
South around/after midnight. North MS will be mostly dry overnight.
Shower and thunderstorm chances will to tail off north to south
as the front moves through Tuesday. Still expect quite a bit of
humidity tomorrow ahead of the front with dewpoints in the mid
70s. Heat index values will be near 105 possible from
Memphis...south through the Delta region.
Tuesday night through Friday...Drier air will filter in the region
during this period with plenty of sunshine under upper level
ridging. Expect dewpoints in the 60s and highs in the 80s to
around 90.
Weekend...A weak mid level trough will move over the area this
weekend with increased humidity levels and chances for showers and
thunderstorms returning. Models start to diverge early next week
with some major difference between the operational GFS and ECMWF
concerning the amount of upper ridging across the mid MS Valley.
The GEFS points to a warmer/drier early next week while the EPS is
cooler and wetter. Taking the middle road for now.
SJM
&&
.AVIATION...
(00Z TAFS) Issued at 0640 PM CDT Mon Aug 29 2022
SHRAs and TSRAs will affect MEM and TUP in the short term
respectively. Thereafter, VFR conds shall prevail for a few hours.
Another complex of TSRAs is expected to track SE through JBR and
eventually affecting MEM around midnight. Carried VCTS at both of
those sites and added a tempo for MEM and the accompanying wind
shift. Winds will remain mostly light and variable overnight,
shifting to the west and northwest by tomorrow afternoon behind a
front.
AC3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
Area Forecast Discussion
National Weather Service Miami FL
754 PM EDT Mon Aug 29 2022
...New SHORT TERM, AVIATION...
.SHORT TERM...
(Tonight through Tuesday)
Issued at 745 PM EDT Mon Aug 29 2022
Latest RAP analysis shows high pressure over the western Atlantic,
an upper level TUTT over the Caribbean, and a mid-level inverted
trough over Cuba and nosing up into SW FL. PWAT value off the 12Z
sounding was an impressive 2.47 inches, which is a bit higher than
the HREF forecast of around 2.2 inches. Gusty showers and isolated
thunderstorms impacted the Atlantic coast this morning, with some
impressive gusts of 40-50 mph gusts measured at several locations
right along the coast. After a bit of a lull, convection is
developing this afternoon over the Interior and Gulf coast and will
continue through this evening, before waning late tonight to
isolated/scattered showers and storms overnight. Any storm this
afternoon into early evening will have the potential for strong
gusty winds, and the potential for some localized street flooding.
Low temps tonight in the mid to upper 70s, and around 80 near the
coast.
Forecast soundings show mid-level dry air intrusion on Tuesday. PWAT
values fall back to around 1.6 inches east coast to around 2 inches
west coast. Overall expecting less coverage of convection,
especially along the east coast, but Interior and Gulf coast areas
will still have fairly high PoPs during the afternoon and early
evening hours. With the less coverage expected, afternoon high temps
will likely be a couple degrees higher than today, with most areas
reaching the lower 90s. Combined with the high humidity, peak heat
index values will once again be over 100 degrees, with some inland
locations likely peaking around 105 degrees.
&&
.LONG TERM (Tuesday night through Saturday)...
Models synoptic scenario for the beginning of the long term has
not changed too much with latest runs, with weakening high
pressure across the SE CONUS keeping light SE winds over SoFlo.
This pattern will also result in continuing bouts of convection
along the east coast during the morning hours, then favoring
interior and Gulf coast areas in the afternoon/evening hours due
to sea breeze development and outflow boundary interactions. Thus,
main hazard will be potential for localized flooding under
heavy/persistent downpours Wednesday.
By Thursday and heading into the weekend, long range models depict a
long wave trough developing across the eastern seaboard and
extending into the NE GOMEX. The trough and its associated sfc
boundary do not seem to push further south than maybe the northern
portions of the Florida Peninsula, but should influence the regional
airmass enough to briefly veer winds over SoFlo to a more southerly
flow on Thursday, bringing moisture and a more unstable airmass
across the region. Steeper lapse rates, increasing PWATs, and
cooler 500 mb temps around -8 Celsius will result in slightly
better conditions for deep convection to develop Thursday and
Friday. Sea breeze interactions will again provide dynamic lifting
and become focal points for convection, with a significant
flooding threat for the east coast metro areas. Isolated strong to
severe wind gusts may also be possible.
The trough and sfc boundary gradually break down during the weekend,
allowing for the west Atlantic ridge to expand back into the region.
Expect moderate easterly winds to return, along POPs decreasing into
the high-end scattered coverage.
Afternoon maximum temperatures through most of the long range should
reach the low to mid 90s, with heat indices reaching 100 degrees
over the coasts, and possibly exceeding 105 degrees for portions of
the interior.
&&
.AVIATION...
(00Z TAFS)
Issued at 745 PM EDT Mon Aug 29 2022
VFR now prevailing at all Atlantic terminals as showers remain
over the coastal waters to the east of the airports. APF could still
experience periods of MVFR/IFR vis/cigs under heavy rain through
around 01Z. VFR should prevail overnight, but a few passing
showers can`t be ruled out. Increasing showers in the vicinity of
the terminals may also bring restrictions after 15Z. Mainly SE
winds will continue through the TAF period, with possible gusty
periods after 18Z for the Atlantic terminals. APF will experience
SSW winds after 18Z as onshore flow develops.
&&
.MARINE...
Modest winds out of the southeast continue, while winds over the
Atlantic waters may be breezy at times (10-15 kts), possibly
resulting in brief periods of cautionary conditions. Scattered to
numerous showers and thunderstorms will be possible through the next
several days, which may result in locally hazardous conditions. Seas
will generally remain below 2 to 3 feet in height, and mostly benign
boating conditions should prevail except near showers and
thunderstorms.
&&
.BEACHES...
The rip current risk for the east coast remains limited through the
next several days, however a pronounced easterly flow develops
Friday through the weekend, which may result in an elevated risk for
rip currents.
&&
.PRELIMINARY POINT TEMPS/POPS...
Miami 80 92 80 92 / 40 50 20 60
West Kendall 77 92 75 93 / 40 50 20 60
Opa-Locka 80 93 79 93 / 40 50 20 60
Homestead 78 90 77 90 / 40 40 20 50
Fort Lauderdale 81 91 80 91 / 40 40 20 60
N Ft Lauderdale 81 90 80 90 / 40 40 20 60
Pembroke Pines 79 92 78 92 / 40 40 20 60
West Palm Beach 78 92 77 91 / 40 40 20 60
Boca Raton 80 92 78 93 / 40 40 20 60
Naples 77 90 77 90 / 60 70 40 70
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
GM...None.
&&
$$
SHORT TERM...99
LONG TERM....AR
AVIATION...AR
Area Forecast Discussion
National Weather Service Norman OK
1055 PM CDT Mon Aug 29 2022
...New AVIATION...
.SHORT TERM...
(This evening through Tuesday)
Issued at 125 PM CDT Mon Aug 29 2022
Main concern in the short term is the potential for slow-moving
convection to lead to isolated instances of flooding and severe wind
gusts. Convection has developed late this morning into early this
afternoon north of I-40. A complex of storms is located in Payne
County. Outflow has been surging southward from this complex, which
is likely leading to an overall weakening trend in convective
strength. This activity should exit the forecast area early this
afternoon.
Other showers exist further to the west and southwest. Morning AM
guidance struggled to depict this convection, reducing confidence in
overall evolution of this activity. However, RAP forecast soundings
show an environment characterized by very steep low-level lapse
rates and ample instability (MLCAPE in excess of 2,500 J/kg). Thus,
there is no reason to doubt the eventual maturation of this activity
into slow-moving thunderstorms.
This activity will likely move very slowly initially, with sfc-8km
shear around 10 kts. This combined with PWAT values in the range of
1.8-1.9 inches will enhance the potential for flooding with any
areas the receive convection for a sustained period of time, as well
as the potential for water-laden downbursts. Expect that as
convection matures and cold pools merge, activity will eventually
propagate southward to the I-44 corridor. HREF/WPC guidance has
highest QPFs from SPS to OUN to SUD this afternoon, where potential
for flooding is highest. This round of storms will weaken with the
loss of diurnal heating this evening.
The next round of storms will impact the forecast area overnight as
a wave travels south-southwestward around the Southwest ridge and
pushes a cold front southward into the area. Steering flow will be
stronger with this round of storms, so not expecting any major
flooding issues except possibly in areas that received heavy rain
during the afternoon. This frontal convection should exit the
southern part of the forecast area shortly after daybreak tomorrow.
The cold front will likely stall in southern Oklahoma and provide
the focus for the redevelopment of storms across southern Oklahoma
and western North Texas tomorrow. Temperatures should remain
seasonable through the short-term forecast period.
Meister
&&
.LONG TERM...
(Tuesday night through next Sunday)
Issued at 320 PM CDT Mon Aug 29 2022
The Southern Plains will remain on the eastern edge of a ~596 dam
mid-level ridge centered across the western United States. As a
result, temperatures will remain near to slightly above-average
through the week--but should remain "in check" from becoming too
hot.
The greatest uncertainty is the period from Friday into Saturday.
While most of the ensemble guidance is dry, there are indications
there might be a mid-level weakness that increases the
probability for convection. For now, will keep the forecast dry
(<15% PoPs); however, showers/storms may have to be introduced in
subsequent forecasts.
By early next week, increasing tropical moisture from the
southeast will increase the probability of at least daytime
convection. This may also lower high temperatures by at least a
couple degrees.
Mahale
&&
.AVIATION...
(06Z TAFS)
Issued at 1046 PM CDT Mon Aug 29 2022
Most storms in the area have dissipated, bringing thunderstorm
chances down for the night. Additional development will be
possible again tomorrow along and near the Red River, but chances
are too low at this point for mention in the TAFs. Otherwise light
winds gradually shifting around to the east and VFR conditions
are expected to prevail.
Day
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 93 72 92 67 / 50 30 20 0
Hobart OK 96 71 93 69 / 50 30 20 10
Wichita Falls TX 96 72 93 72 / 40 70 50 10
Gage OK 95 68 92 63 / 30 30 10 0
Ponca City OK 95 70 93 62 / 60 20 10 0
Durant OK 94 72 93 72 / 30 60 50 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...None.
TX...None.
&&
$$
SHORT TERM...04
LONG TERM....10
AVIATION...14
Area Forecast Discussion
National Weather Service Phoenix AZ
434 PM MST Mon Aug 29 2022
.UPDATE...
Updated Aviation section.
&&
.SYNOPSIS...
Excessive heat warnings are in effect for many areas, including
Phoenix, beginning Tuesday. Prolonged hot temperatures are forecast
across the Desert Southwest. Many lower desert areas will eclipse
the 110 degree mark this week, with the California deserts likely
experiencing multiple afternoons of 110 plus degrees. With high
pressure in place, thunderstorm chances will lessen considerably
on most days and affect primarily higher elevations.
&&
.DISCUSSION...
***EXCESSIVE HEAT WARNING BEGINS TUESDAY FOR METRO PHOENIX, SOUTHWEST
ARIZONA, AND SOUTHEAST CALIFORNIA***
It`s a dry, sunny, and hot Monday across the region. Upper high
pressure is building over the Southwest and mid-altitude moisture
has scoured out. These factors leave us with less opportunities
for clouds and storms this week. Replacing the monsoon moisture:
intense heat.
Over the next several days, a preponderance of the guidance shows a
500mb high pressure center expanding, strengthening, and moving
little over the Southwestern U.S. By Wednesday, 500mb heights will
approach 595 dam. This is near to just above the maximum moving
average for the time of year. Looking a little closer toward
ground level, 850 mb temperatures peak between +28C and +31C
during the next 72 hours. This corresponds to widespread MaxTs
from 108-115 across our lower deserts tomorrow, Wednesday, and
Thursday (hottest in SE CA). This is approaching or even locally
exceeding our high HeatRisk threshold. Many of us have not
experienced 110+ temperatures in several weeks due to the active
monsoon pattern.
To make matters more miserable, there will be occasional surges of
Gulf of CA moisture rising over parts of SW AZ and SE CA. Even right
now, dew points are well into the 70s over the Imperial Valley.
These moisture surges will be most noticeable in the morning
hours, when the apparent "feels-like" temperatures can peak some
10-15F above the actual air temp. This moisture mixes out and
decreases some by afternoon, but with 110+ temps, there is no
solace here.
Nighttime readings will not offer much relief, either. All lower
deserts will see low temperatures in the 80s. Around Central
Phoenix, the NBM suggests a 10-30% chance of low temperatures at
or above 90F the next few mornings. These odds are likely higher
than the blend is giving us for a couple reasons: 1) bias over-
corrections due to recent "cooler" weather, and 2) low-level
nocturnal winds off the surface of 15-25kt which promotes mixing
well into the overnight period. Case in point for earlier today:
the NBM gave a forecast low of 84... PHX only fell to 89.
All of these factors led us to upgrade to an excessive heat warning
for Metro Phoenix, SW AZ and SE CA beginning tomorrow. For SW AZ and
Phoenix, the highest heat impact days are currently forecast for
Tuesday and Wednesday, so the warning in these areas expires
Wednesday night.
Even beyond this timeframe, we will continue to see at or above
normal temperatures. Utilizing the cluster approach, ensemble
guidance strongly agrees that we will have deep-layer ridging over
the West at least through Labor Day weekend. By Saturday night,
the ridge axis is forecast to nudge a little farther northwest,
centering from the Great Salt Lake to Monterey, CA. Expect the
most anomalous heat will shift a little bit as well... over
California and up into Nevada. Thus, the excessive heat warning
for SE Cali and the CO Valley will continue through Labor Day.
The prolonged nature of this heat is quite dangerous.
.PREVIOUS DISCUSSION... (Monsoon Setup & Storm Potential)
On the thunderstorm potential side of things, chances are very
limited through the week, with NBM PoPs <10% through the next 7
days for the lower deserts and mostly 10-20% for Southern Gila
County. A large reason for the low PoPs is likely due to the
drier air in the short term and warmer air aloft. The synoptic
setup at least will be a classic Maddox et al. Type II high setup
which is historically synonymous with Rim-to-Valley severe storms
and PV anomalies fracturing off from the jet stream to then
retrograde under the high. One such PV fracture is expected over
New Mexico through today before sliding through Southeast Arizona
and Northern Sonora Tuesday-Wednesday. The extended HRRR runs are
now trying to bring storms in through Southern Gila County and
toward the Valley on Tuesday. However, Tuesday is expected to be
the driest day of the week with PWATs down near 0.9-1.1", and one
of the hottest days. So, this may be a bit of a stretch, but if a
storm is able to survive it would likely be discrete. The Valley
is more likely to only see some mid-level debris clouds coming off
the Rim. Wednesday could perhaps have a better chance with a
slight boost in moisture. Moisture is expected to continue
increasing, with PWATs climbing back to around 2.0" by the end of
the week with additional northeasterly waves possible. So, there
may be one or more good days Friday into this weekend for Rim-to-
Valley storms.
&&
.AVIATION...Updated 2334Z.
South-Central Arizona including KPHX, KIWA, KSDL, and KDVT:
A decline in moisture has brought about a continued decline in
thunderstorm activity today such that outflows are not expected to
affect the TAF sites tonight. Northwest/west winds will prevail
this evening with a slow trend toward light and variable favoring
downvalley/easterly directions overnight. Southeast directions
will be favored during the morning and into the afternoon before a
late transition to southwesterly at KDVT and KSDL but remaining
southeasterly at KIWA. Light and variable at KPHX during the late
afternoon early evening. An uptick in storm activity is
anticipated over southeast AZ Tuesday afternoon and evening such
that southeasterly outflows could affect the metro area in the
evening. Too much uncertainty at this point to reflect in the
in the 30 hour TAF for KPHX. Otherwise, very little cloudiness.
Southeast California/Southwest Arizona including KIPL and KBLH:
KIPL: East/southeast winds are expected this evening before
becoming more variable overnight and continuing that way during
the day with directions flopping around between
southeast/southwest/northwest. Otherwise, clear skies.
KBLH: Southwest and west directions are expected to be favored for
much of the night before a lot of directional variability
develops toward morning and continues through the day Tuesday.
Otherwise, clear skies.
&&
.FIRE WEATHER...
Substantial warming and drying through early this week will see
afternoon MinRH values fall to 15-25% and persist through most of
the week, while overnight MaxRH recovers to around 40-60% most
places. Afternoon temperatures will be several degrees above
normal for much of the next week. Shower and thunderstorm chances
will be very limited through the week, focused mainly in the AZ
high terrain areas. Apart from thunderstorms, winds will follow
familiar diurnal patterns.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...Excessive Heat Warning from 10 AM Tuesday to 8 PM MST Monday for
AZZ530.
Excessive Heat Warning from 10 AM Tuesday to 8 PM MST Wednesday
for AZZ531>533-535>537-540>544-546-548>551.
CA...Excessive Heat Warning from 10 AM Tuesday to 8 PM MST Monday for
CAZ560>570.
&&
$$
DISCUSSION...Heil
PREVIOUS DISCUSSION...Benedict
AVIATION...AJ
FIRE WEATHER...Benedict
Area Forecast Discussion
National Weather Service Tulsa OK
921 PM CDT Mon Aug 29 2022
...New SHORT TERM...
.SHORT TERM...
(The rest of tonight)
Issued at 909 PM CDT Mon Aug 29 2022
What turned out to be a rather active afternoon/evening has calmed
down as most storms have now moved into NW Arkansas or SC
Oklahoma. For the most part the overnight period should remain
rather quiet, however at least some degree of instability will
linger above the rain-cooled air at the sfc, plus modest moisture
transport makes it difficult to completely write off additional
showers or isolated storms overnight. This is at least hinted at
in the 00z 3km NAM and the last few HRRR runs. Keeping a slight
chance of thunder overnight and will remove mot POPs through 06z
in an update, which will be issued shortly.
&&
.LONG TERM...
(Tonight through Monday)
Issued at 127 PM CDT Mon Aug 29 2022
A frontal boundary will advance south across the region Tuesday,
in response to a strong shortwave trough sliding across the
Midwest and Great Lakes. While the meteorological term for this
boundary is a cold front technically, it will not feel "cold"
behind this boundary. We will notice the much drier air, at least.
Isolated to widely scattered storms are possible, mainly I-40
south. The much drier deep layer airmass behind the front will
bring hot and tranquil weather from Tuesday evening thru the end
of the week. Rain/storm chances will return by the latter part of
the weekend, especially in the terrain, as moisture returns to the
region from the southeast.
Lacy
&&
.AVIATION...
(00Z TAFS)
Issued at 646 PM CDT Mon Aug 29 2022
Stronger thunderstorms have shifted east of NW AR TAF sites early
this evening. Still the potential for thunderstorms/brief IFR
conditions at KMLC/KFSM for the next couple of hours near outflow
boundary. Depending on mid clouds tonight, could see some patchy
dense fog develop toward morning. For now, only included TEMPO
groups for NW AR sites, but this will need to be monitored. A
few storms may develop along the I-40 corridor Tuesday afternoon,
near frontal boundary, but coverage is too limited to include at
this time.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 72 93 63 94 / 20 20 0 0
FSM 74 95 70 95 / 40 20 0 0
MLC 72 93 70 94 / 30 20 10 10
BVO 68 93 59 93 / 20 20 0 0
FYV 68 90 60 89 / 50 20 0 0
BYV 70 89 60 89 / 40 20 0 0
MKO 71 91 64 92 / 20 20 0 0
MIO 69 90 58 91 / 20 20 0 0
F10 70 93 63 93 / 20 20 0 0
HHW 72 90 72 93 / 30 30 10 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...None.
AR...None.
&&
$$
SHORT TERM...14
LONG TERM....30
AVIATION...12
Area Forecast Discussion
National Weather Service Las Vegas NV
806 PM PDT Mon Aug 29 2022
.SYNOPSIS...Monsoon concerns continue to wane while heat takes the
stage for the upcoming week. A high confidence, long duration
heat event will begin tomorrow and potentially last through the
Labor Day Weekend. There is some uncertainty toward the end of the
period on whether this event continues or subsides, but through
the rest of the week at least, heat will be the main impact
concern.
&&
.UPDATE...Quiet evening across the area as the afternoon showers and
storms have all dissipated. Even less activity expected tomorrow as
the upper-level high begins to build overhead. Heat continues to be
the main weather story, with Excessive Heat Warnings going into
effect tomorrow. The heat is likely to persist through at least
Sunday, with some moisture and low storm chances creeping into our
southeastern areas over the weekend. Updated forecast package will
be out tonight.
&&
.SHORT TERM...Today and Tonight.
Moisture is slowly but surely expected to decrease across the
region and has dropped a few degrees already this morning across
the LV Valley. That being said, dewpoints well into the 50s
remains as far north as Clark County and satellite trends as of
19Z show CU development over many of the high terrain areas. Radar
shows light showers and a few cloud flashes over Nye county as
well. 12Z HREF maintained isolated convection with a favoring of
the HWY 93 corridor and the high terrain of Clark county. Since
12Z, HRRR runs continue to advertise convection over the
McCullough range with some signals for outflow generation into the
southern LV Valley. Opted to increase PoPs per these trends and
WPC QPF also aligned with this thinking.
All of this activity should subside by nightfall and leave the
region with mostly clear skies and light winds.
.LONG TERM...Tuesday through Next Weekend.
The focus of the long term is the prospect of long duration
anomalous heat throughout the week and into the holiday weekend.
A typical setup of H5 ridging squarely over the CWA will set up as
early as tomorrow and strengthen rather quickly. EC ensemble means
show a +2 sigma high over much of the Desert Southwest with little
change in overall pattern through Friday. In fact, H5 means
intensify further by next weekend per the EC. GEFS means do show a
slightly different orientation to the ridge through the week,
especially by the weekend when it depicts Pacific troughing
nudging the axis further west, but regardless, above average heat
looks increasingly likely to linger through the holiday weekend.
&&
.AVIATION...For Harry Reid...Minimal to minor impacts possible
today for Harry Reid terminal. A low but increasing probability
for afternoon thunderstorms will continue through the afternoon in
the vicinity of the valley which could push out an outflow into
the southern valley. Did not include this in the TAF but did
introduce VCTS. Amendments will be needed if outflow ends up
impacting the terminal directly. Otherwise, generally light
diurnal winds expected.
For the rest of southern Nevada, northwest Arizona and southeast
California...Very isolated TSRA expected across the region,
mainly a concern for the LV Valley sites and to a lesser extent
KIFP/KEED. KBIH will experience upvalley winds with gusts as high
as 30 kts this afternoon but subside after dark. Very little cloud
cover expected otherwise.
&&
.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&
$$
UPDATE...Woods
DISCUSSION/AVIATION...TB3
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