Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/01/23
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
905 PM CDT Wed May 31 2023
.UPDATE...
Issued at 856 PM CDT Wed May 31 2023
CWA is free is precipitation currently, and based on recent runs
of the HRRR and other CAMs, been cutting back on PoPs through the
rest of the night. Several boundaries floating around the region
from earlier convection, some of which are visible on radar.
Surface obs also continue to indicate the presence of the main
boundary draped across the region. Not much to hang your hat on
for overnight shower/storm chances and will likely have to wait
until tomorrow afternoon for any noteworthy redevelopment. Only
minor modifications to other weather elements for the overnight
hours.
&&
.SHORT TERM...(This Evening through Thursday Night)
Issued at 230 PM CDT Wed May 31 2023
Our unsettled weather pattern and warmer than average temperatures
continue through the short term. Deterministic and ensembles agree
on a ridging pattern across the central and eastern CONUS with a
trough in the western CONUS and mid level low centered over CA/AZ
this evening. This will continue to provide southwest flow at 500mb
with wind speeds at 15kts at most. This pattern continues through
Thursday with winds at this level turning more southerly Thursday
afternoon then southeasterly by Friday morning (15-25kts) as the low
moves northeast. Several shortwave pulses will push from the
southwest towards the northeast then wrap back west around the low
as it moves northeast, mainly over central and western SD through
Friday. This whole pattern really only shifts slightly east over the
next few days. Models do show an increase in wind speed overnight at
850mb (LLJ) across our central and western CWA with speeds up to 25
kts per NAM/GFS. EC has some higher speeds (up to 32 kts). At the
surface, a trough sets up over the CWA this evening and tonight with
winds out of the south/southeast and more east/southeast Thursday
and increasing Thursday afternoon and again Friday mainly across
central and western SD.
As of 200 PM, Satellite/RAP model continues to show the vort max/MCV
hybrid pushing into ND. Ongoing showers and thunderstorms continue
to push northeast and are weakening. Earlier, we had some modest
CAPE, steep low level LR, and the slightest low level curvature on
the hodograph over eastern/northeastern SD/western MN per Rap model
where some of these storms had some very weak rotation to them,
especially early on in the storm`s life. We did have a warning on one
of the cells for quarter size hail and 60 mph winds. No organized
severe weather occurred as overall bulk wind shear remained low.
Models have really backed off on the chances of pops for late this
afternoon and evening behind this line of storms. So went with more
of a broad brush slight chance wording. This may even need to be
taken out if nothing forms. Same story again for Thursday with
similar ingredients in the atmosphere and synoptic setup, more
spotty chances of showers and thunderstorms expected. Again, no
organized severe weather expected but some could pulse high enough
to produce some small hail and gusty winds.
.LONG TERM...(Friday through Wednesday)
Issued at 230 PM CDT Wed May 31 2023
In the out periods, the biggest forecast challenges will focus on
thunderstorm chances and temperatures.
This CWA will be influenced heavily by high pressure in the
mid/upper levels of the atmosphere. An overall/over-arching upper
level ridge in place over the eastern two-thirds of North America
will support the retrogression of an area of upper level high
pressure, currently over the east CONUS coastline, westward into the
country`s mid-section up into southern Canada throughout the period.
Ensemble-based PoPs are rather generous through the period, given
the lack of an adequate forcing/lift signal on any given day.
Similar to the past couple of weeks, precipitation chances are
either a result of previous convection-leftover OFB-forcing,
nocturnal low-level jet-forcing, or convection that rolls down out
of the higher terrain of the central/northern high plains.
Ensemble-based probabilities of temperatures reaching or exceeding
90 degrees are still targeting portions of the southwestern and
eastern forecast zones several days in the extended, as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 638 PM CDT Wed May 31 2023
Terminals KABR,KATY,KPIR,KMBG
VFR conditions are forecast through the TAF period. Just a very
slight chance for a stray -TSRA/SHRA this evening/overnight. Will
await Thursday afternoon before any more potential meaningful
coverage of -TSRA/TSRA that deserves a VC mention in the TAFs.
Like the past few days, hard to pinpoint exact locations as
coverage will be scattered, but if something were to move over a
terminal, potential exists for MVFR VSBY in heavier downpours.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...TMT
SHORT TERM...MMM
LONG TERM...Dorn
AVIATION...TMT
Area Forecast Discussion
National Weather Service Amarillo TX
702 PM CDT Wed May 31 2023
...New AVIATION...
.MESOSCALE UPDATE FOR HAIL, WIND, AND FLASH FLOODING THREAT FOR
THIS AFTERNOON THROUGH THURSDAY MORNING...
Issued at 216 PM CDT Wed May 31 2023
* Synoptic Overview: The latest H500 RAP analysis shows a upper
level low pressure system continues to remain nearly stationary
near the southern tip of Nevada early this afternoon. This
feature will continue to drift very slowly towards the east
through early tomorrow morning. Out ahead of this feature,
shortwaves embedded in the upper level flow will propagate
across the Southern High Plains beginning later today and will
continue through early Thursday morning. The PVA associated with
these waves will generate numerous rounds of precipitation of
the next 18 hours or so. Southerly winds in the low to mid
levels will allow a decent axis of positive theta-e to move
across eastern NM and West Texas this afternoon through the
overnight hours tonight which will aid in generating a few
rounds of thunderstorms.
* Mesoscale: As of 18z, showers and thunderstorms continue to move
east and northeast across eastern New Mexico. Across the
southwestern and south central TX Panhandle, visible satellite
imagery shows some attempts at a cumulus field trying to develop
over this area. The first run (17z) of the Warn on Forecast
(WoFS) suggests that these showers and storms will move across
the northwestern TX Panhandle later on this afternoon, leaving
the southwest and central portion of the CWA in the clear from
this initial activity. A few isolated thunderstorms may develop
across these areas later on this afternoon in an environment
that will be primed for storms to become strong to severe.
MUCAPE values could be approaching 2500 to 2750 J/kg and bulk
shear values of 20 to 25 kts could lead to a few strong to
severe isolated supercells. The next upper level wave will be
approaching the High Plains by early this evening and a line of
storms will begin to move across the Panhandles. Before this
line approaches, if any storms are able to remain discrete out
ahead of the line, a marginal tornado threat may be possible as
low level shear begins to increase in response to stronger H850
winds moving over the area. The main threats with the
aforementioned line of storms will be strong wind gusts up to 75
mph and torrential rainfall. Cannot rule out a quick tornado
spin-up along this line as the low level shear increases.
Forecast PWAT values continue to remain around the
climatological max for late May/early June and forecast
soundings continue to depict a very moist profile this evening
through early tomorrow morning. Multiple rounds of showers and
thunderstorms are possible through tomorrow morning, which is
leading to a high concern for flash flooding, especially if
storms train over the same areas.
* Threats: The primary hazards with the storms today will be large
hail, damaging wind gusts, and flash flooding. The large hail
threat will be the highest with any discrete supercells during
the mid to late afternoon across the central and west where hail
up to golf ball size will be possible should any storms develop
out ahead of the main line. Damaging wind gusts up to 75 mph are
possible as a line of thunderstorms moves across the Texas and
Oklahoma Panhandles this evening. The tornado threat is low, but
cannot rule out one or two especially if any supercells can
remain discrete enough closer to sunset once the stronger low
level winds begin to ramp up. The main hazard with the showers
and storms will be the flash flood threat. This is due to
already very saturated soils and the ongoing flood concerns of
lakes, rivers, and streams. Very heavy rainfall is possible with
rain rates up to 2 to 4 inches per hour with the strongest
storms.
* Timing & Location: Multiple rounds of showers and thunderstorms
are expected starting in the middle of the afternoon through
early Thursday morning. A few discrete thunderstorms may form
across the western and central Panhandles during the middle to
late afternoon today. A line of showers and storms is expected
to move across the Panhandles this evening. Some of these storms
could be strong to severe. Overnight tonight through early
Thursday morning, multiple rounds of showers and storms are
possible across the entire area. The severe threat will decrease
after midnight, but a few strong to severe storms will remain
possible.
Muscha
&&
.SHORT TERM ...
(This evening through Thursday night)
Issued at 216 PM CDT Wed May 31 2023
Synopsis: A few rounds of thunderstorms are expected starting this
afternoon and potentially lasting into Thursday morning. Some
storms may be severe mainly before midnight, with large hail and
damaging winds being the main threat. The bigger concern tonight
will be potential for flooding and flash flooding, and this threat
will extend into tomorrow. Another round of severe storms is
possible tomorrow, but there is a chance that the area becomes
worked over and possibly socked in with clouds which would limit
that threat. More details for today`s severe/flood threat will be
laid out in the mesoscale discussion. Details on tomorrow`s threat
can be found below.
Details:
Showers and storms may be ongoing Thursday morning as shortwaves
continue to eject out ahead of an H5 low near the Four Corners.
This low will weaken some but the center won`t move much through
the day leading to continued moist return flow and broad lift in
proximity to a left jet exit region. If the area can destabilize
going into the afternoon (which most of the ensembles believe will
occur), then thunderstorms may develop once again mainly favoring
the southern TX Panhandle. The exact location of storm initiation
will depend on the position of a left over outflow boundary and
dryline. If storms do develop, some increased flow in the mid and
upper levels will support effective shear in the 30 to 40 knot
range which would support supercell development with a risk for
large hail and damaging winds (low tornado chance due to lacking
low level shear, but not out of question). Shortwave passage in
the evening (along with increased low level jet) may upscale
growth into QLCS structure across the east, but at this time it
does`t look like storms will be ongoing all night as the area goes
into a brief period of subsidence behind the impulse.
Ward
&&
.LONG TERM ...
(Friday through next Tuesday)
Issued at 216 PM CDT Wed May 31 2023
Synopsis: Bottom line is the pattern doesn`t change much as the
blocking pattern keeps reloading H5-H25 low pressure over
portions of the Desert Southwest. This keep a subtropical jet
going over the southern plains and almost daily shortwave
disturbances with ample moisture (PWATs remain above normal).
Thus, daily thunderstorm chances can be expected and this will
include at least some risk for severe storms and especially
flooding as the area lakes, creeks, and rivers continue to rise.
Friday will see a fairly significant shortwave that could result
in another round of widespread heavy rain.
Ward
&&
.AVIATION...
(00Z TAFS)
Issued at 656 PM CDT Wed May 31 2023
For the 00Z TAFs, periods of showers and thunderstorms are expected
at the terminal sites tonight through Thursday morning as an upper
level storm system impacts the area. These individual waves of
showers and storms will be hard to time for the TAF sites, as will
any vsby and cig issues. Therefore, this is a low confidence forecast
with amendments possible as the evening unfolds.
02
&&
.PRELIMINARY POINT TEMPS/POPS...
Amarillo TX 59 74 58 77 / 100 70 40 60
Beaver OK 60 80 59 81 / 50 60 30 60
Boise City OK 55 73 53 78 / 60 60 20 30
Borger TX 61 78 60 81 / 90 60 40 50
Boys Ranch TX 58 75 58 78 / 100 70 30 50
Canyon TX 58 75 57 77 / 100 70 40 70
Clarendon TX 60 77 59 78 / 90 60 40 70
Dalhart TX 55 72 54 76 / 90 60 30 40
Guymon OK 58 76 56 79 / 80 50 30 40
Hereford TX 58 76 57 76 / 90 70 30 60
Lipscomb TX 61 80 59 80 / 60 50 40 60
Pampa TX 59 76 58 78 / 90 60 40 60
Shamrock TX 62 80 60 80 / 80 50 50 70
Wellington TX 64 82 61 81 / 70 50 40 70
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...Flood Watch through Thursday morning for TXZ001>003-006>008-
011>013-016>018-317.
OK...Flood Watch through Thursday morning for OKZ001-002.
&&
$$
SHORT TERM...05
LONG TERM....07
AVIATION...02
Area Forecast Discussion
National Weather Service La Crosse WI
1100 PM CDT Wed May 31 2023
.DISCUSSION...(This evening through Wednesday)
Issued at 150 PM CDT Wed May 31 2023
Key Messages:
- Low risk for showers and storms this afternoon and tonight
(10-20%) across southeast Minnesota and northeast Iowa.
- Scattered storm risk for Thursday, with lessening confidence
for Friday and the weekend.
- Unseasonably warm stretch of weather persists through the
weekend with the hope for a cooler stretch of weather fading
for early next week.
Rainfall Hopes for the Next Week...
An MCV developed in conjunction with a complex of storms that worked
out of northern Iowa this morning, tracking across the western
forecast area and bringing light to moderate rainfall to locations
from Saint Ansgar to Lake City. The residual cold pool trailing this
MCV may be the focus for renewed convective development, though the
rapid air mass recovery observed in its wake does not bode well for
new convection later today and have capped the precipitation grids
at 20 percent. A weak convergence zone over southern and central
Wisconsin will also be the focus for showers and thunderstorms this
afternoon, but the overall coverage looks sparse and likely just
east of the forecast area. As with the last few days, the lack of
deep shear and minimal steering flow will result in disorganized,
pulse convective structures that will pose little more than a
lightning and gusty wind threat. The slower storm motions will
result in decent rainfall rates for those areas that find themselves
under a stronger updraft, but such updrafts will be hard to come by
this afternoon and tonight.
Moving into Thursday, a weak upper level perturbation works through
the longwave ridging and may provide enough support to kick start
scattered showers and storms at peak heating. The HRRR and other
members of the 31.12Z HREF do depict this scenario and have pushed
PoPs up into the 30-50 percent range during the afternoon. The
lack of a forcing mechanism and dry boundary layer will act to
limit the overall coverage of the storms.
The upper ridge strengthens during the day on Friday with the center
of the ridge axis centered through Minnesota. It is interesting
(bizarre?) to note the large PoP values from the global
deterministic/ensemble members despite the unfavorable synoptic
pattern. Have manually lowered PoPs by 20-30 percent over the NBM
and as the CAMs are assimilated over the next 24-36 hours, it is
likely--given the wet bias of the global models--that these PoPs
will fall further.
Heading into the weekend, confidence in the precipitation forecast
degrades further as differences arise in the longwave pattern,
mostly pertaining to whether any shortwaves work down the east flank
of the ridge. Have maintained the low (20-30 percent) NBM PoPs for
this time range, though we should stay primarily dry into next week
with just a few, low probability shots of rain.
The Heat Continues...
The overall temperature/dewpoint forecast changes little through the
weekend given the weak flow pattern and minimal changes to the lower
tropospheric air mass. The dry soils have allowed temperatures to
overachieve the NBM guidance and have pushed values slightly above
the deterministic progs in favored regions. Ensembles are tightly
clustered around the mid-80s to low 90s through the weekend before a
vort lobe drives down the east flank of the upper level ridge early
next week. This trough ushers a polar airmass southward with dew
points possibly falling into the 30s and 40s again by midweek. The
strength of this continental polar airmass and position of the
central CONUS ridge remain a source of variability in the forecast
and recent ensemble trends have been shifting this push of cooler
air further east, lessening the impacts and keeping highs at or
above average for this time of year over the region. We still
reside on the periphery of this pattern shift, so the forecast can
still change over the coming days.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1055 PM CDT Wed May 31 2023
Increasing moisture transport and theta-e advection into the area
this evening led to some isolated showers in the area. Some hint
that an MCV over MO will lift north across Iowa into the forecast
area. With a moist and unstable airmass in place, we`ll continue
to see isolated to scattered showers and thunderstorms increase
for Thursday. For now included variable mid and high level clouds
and a prob30 for tsra at KLSE Thursday afternoon and early
evening. Will need to monitor in the short term for adding any
additional shra/tsra.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
DISCUSSION...Skow
AVIATION...Zapotocny
Area Forecast Discussion
National Weather Service Binghamton NY
943 PM EDT Wed May 31 2023
.SYNOPSIS...
High pressure will remain over the region with dry and warm
conditions through the end of the week. A backdoor cold front
will increase chances for rain and bring cooler temperatures
across the area on Saturday into Sunday.
&&
.NEAR TERM /THROUGH THURSDAY NIGHT/...
930 PM Update...
Evening temps remain right on track with widespread mid 60s to
low 70s across the area. Ran the latest HRRR smoke guidance and
updated the forecast with the new output. Looks like the best
chance for patchy smoke making it to the ground will be across
NEPA and far southern Catskills with haze move into the eastern
Southern Tier and Catskills. The rest of the forecast remains on
track.
630 PM Update...
Some fair weather cumulus clouds that developed this afternoon
over the Finger Lakes are beginning to dissipate as afternoon
heating subsides. Currently, temps in the low to mid 80s are
hanging on across the region. Dry air will allow for temps to
quickly cool over the next few hours as the sun begins to set.
For example, Syracuse, currently at 87, is expected to be at 74
by 9pm. Across the region, upper 60s to mid 70s are expected by
9pm.
The forecast for tomorrow remains on track from the afternoon
package. Some slight adjustments were made based on new model
guidance, but mid to upper 80s expected across the CWA with
river valleys in the low 90s.Clear, dry and warm this evening
with
145 PM Update...
High pressure remains parked over the region, with dry
conditions and warm temperatures continuing. Although
temperatures will reach into the mid to upper 80s on Thursday,
humidity will remain low with dew point temperatures in the 40s
to low 50s.
Smoke, produced from a wildland fire in Nova Scotia, may push
into NE PA and the Southern Tier late tonight and early Thursday
morning as onshore southeasterly flow develops. Although,
patchy smoke and haze will likely be observed, we are not
expecting a reduction to visibility at this time. Low level flow
will start to turn out of the north by tomorrow afternoon and
this should push any smoke back out of the region.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Another day of summerlike warmth and relatively low humidity is in
store Friday as high temperatures climb into upper 80s and low 90s,
then some changes are on the way that will lead to an increase
in clouds and even the chance for a little wet weather. The
upper-level ridge that has been in place the past several days
will retrograde back to the west Friday and a weak shortwave
will drop in from the north during the afternoon and evening.
This will produce some scattered clouds and there can be a
spotty shower or two, perhaps even a thunderstorm, into early
Friday night. The best chance for anything stray will be over
eastern parts of the CWA. Later Friday night into Saturday, a
backdoor cold front will slide south over the area and an upper-
level trough will move south out of eastern Canada as well. A
couple of showers will be around Saturday as the front moves
through and perhaps even a thunderstorm, but given the dry air
the boundary is moving into, PoPs look to remain pretty low.
With the frontal passage, high temperatures Saturday will be
mainly in the 70s. Most of the spotty shower activity is
expected to taper off Saturday evening.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Unlike Tuesday afternoon when there was pretty decent agreement in
guidance for Sunday through the first half of next week, the same
cannot be said this afternoon. A cutoff low is expected to form from
the trough dropping southward from Canada, but there`s differences
in the timing of its formation and placement. The GFS is much
quicker with the low forming Saturday night over the northeast and
hovering over the area Sunday. The 00z run even had the low
retrograding westward toward the Ohio Valley. This would lead
to some clouds and perhaps a couple of showers Sunday, and the
shower chance would carry over into Monday and Tuesday as well.
The Euro has this low forming Sunday well off to the east near
Cape Cod and is dry across the CWA to end the weekend. It also
has a couple of weak shortwaves dropping south Monday into
Tuesday with a persistent northerly flow, but little if any
moisture looks to be around. The Canadian forms the low Saturday
night but it`s similar in placement to the Euro, but rotates in
another vort. max from the north Monday and Tuesday that could
spark a shower. Regardless of the uncertainty and the potential
for more clouds to be around, there`s not a great chance of
seeing much in terms of any rainfall with none of these features
emerging from a decent moisture source. Ensembles show fairly
low heights in place through midweek over the Northeast,
supporting seasonable temperatures in the 70s for most into at
least early next week.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
High pressure over the region will continue to bring IFR
conditions and light/variable winds through the forecast
period.
Outlook...
Thursday afternoon through Friday...Mainly VFR.
Saturday through Sunday...Mostly VFR, but some brief
restrictions will be possible from showers.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.
&&
$$
SYNOPSIS...MPK
NEAR TERM...JTC/MPK
SHORT TERM...DK/MPK
LONG TERM...DK/MPK
AVIATION...MPK/MPH
Area Forecast Discussion
National Weather Service Birmingham AL
742 PM CDT Wed May 31 2023
...New SHORT TERM, AVIATION...
.SHORT TERM...
(Tonight through Thursday)
Issued at 722 PM CDT WED MAY 31 2023
The latest RAP analysis has a large moisture gradient over the
southeastern counties near Troy and Eufaula. Previous convection
has allowed a nice outflow boundary to develop and was near
Montgomery to Phenix City. The global models indicate some good
omega near this gradient and slowly moves east to west. These
features were on the far north side of low in the northern Gulf of
Mexico. Most of the activity was showers as the lightning activity
has waned over the past hour. Expect the overall coverage to
eventually lessen in the south, but did have to increase pops for
the early evening hours south. Mean relative humidity remains high
overnight especially south and will monitor if these showers do
indeed all go away.
75
Previous short-term discussion:
(This afternoon through Thursday)
Issued at 1159 AM CDT WED MAY 31 2023
High pressure extends southwest along the Mid-Atlantic coast and
through the Appalachians which is resulting in easterly flow across
Central Alabama. To our south, a mid-level low is developing over
the Central Gulf of Mexico while a Rex Block pattern remains in
place along the East Coast which is resulting in moist onshore flow
along Georgia and Florida. These features will allow for a slight
increase in moisture across Central Alabama over the next couple of
days which will support routine afternoon chances for isolated to
scattered showers and thunderstorms. Dry mid-level air is likely to
remain over the area, especially as 500mb winds become northerly
tomorrow afternoon in response to a breakdown of the Rex Block. This
should help to limit thunderstorm intensity and overall coverage of
rain as mid-level lapse rates are poor, and really the overall
moisture profile is still of low quality. There will be mostly sunny
to partly cloudy skies, but cloud cover may increase at times due to
the trough circulating over the Gulf of Mexico. Nonetheless, expect
warm daytime temperatures with highs in the 80s and mild
conditions overnight with lows in the 60s.
86/Martin
&&
.LONG TERM...
(Thursday night through Tuesday)
Issued at 256 PM CDT WED MAY 31 2023
No major changes were made to the extended forecast. We have slid
into a typical summertime diurnal pattern with isolated heat
induced afternoon and evening convection possible almost every day
in the extended. Although we will continue to monitor the tropical
feature over the Gulf of Mexico, the latest guidance suggests
that the most impactful weather is expected over the Florida
Peninsula as it drifts in that direction.
08
Previous long-term discussion:
(Thursday night through Tuesday)
Issued at 254 AM CDT WED MAY 31 2023
Rain chances from Thursday into Friday look to be largely dependent
on the evolution of the tropical disturbance in the Gulf.
Indications are that while the system should ultimately move to the
east, there could be a couple outer bands that try to push into
southern areas of Central Alabama. Most of this activity will remain
along/just north of the coast, however. Otherwise, nearly every
afternoon looks to have at least a slight chance of isolated to
scattered showers and thunderstorms. Will be watching the evolution
of an upper low over the northeast states this weekend. The GFS
retrogrades the feature back to the southwest, over the Ohio Valley,
by Tuesday, while other models take it out to sea from New England.
As such, the GFS has considerably cooler afternoon temps on Tuesday
vs. the ECMWF. Model blends capture this nicely, and the forecast
splits the difference here for the upper 80s on Tuesday. These temps
are characteristic of the entire period, which will see highs each
day from the mid to upper 80s to occasionally low 90s.
12
&&
.AVIATION...
(00Z TAFS)
Issued at 722 PM CDT WED MAY 31 2023
Low pressure over the northern Gulf of Mexico will keep and
easterly flow over Central Alabama this period. There are some
showers and a few thunderstorms near a moisture gradient over
southern Alabama. Have some mention of convection in for MGM/TOI a
few hours this evening before moving out/dissipating. A brief wind
gust is possible along with brief vis reduction, but most ceilings
will stay VFR. The remainder of the overnight hours will see VFR
ceilings slowly decreasing. Although model output is not
indicating it too much, believe some MVFR ceilings will show up
around sunrise. These clouds will lift with daytime heating and
only last a few hours in restrictions. There will be some drier
air entering the picture on Thursday. Therefore, all areas will
not experience convection. But the exact location will play a role
in where pops are highest. At this time, have PROB30 mention
south and west. Winds remain easterly 5-10kts.
75
&&
.FIRE WEATHER...
Typical diurnal summertime activity is expected through the
forecast with mainly isolated showers and thunderstorms possible
each afternoon. Minimum relative humidity percentages should
continue to decrease a little each day through the next week, but
we should not reach critical values. 20ft winds should remain
from the east to northeast through the weekend and generally less
than 12 mph.
&&
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 62 84 62 88 / 10 20 20 20
Anniston 64 84 64 87 / 10 20 20 20
Birmingham 65 87 66 89 / 20 30 20 20
Tuscaloosa 65 87 66 89 / 20 30 20 20
Calera 65 85 66 88 / 20 20 20 20
Auburn 65 83 65 85 / 20 20 20 20
Montgomery 66 86 66 88 / 50 20 20 20
Troy 65 85 66 88 / 50 30 20 20
&&
.BMX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...75
LONG TERM....08
AVIATION...75
Area Forecast Discussion
National Weather Service Burlington VT
1018 PM EDT Wed May 31 2023
.SYNOPSIS...
Smoky conditions will be possible again tonight across the Champlain
Valley as smoke from Nova Scotia wildfires moves back into our
region. Otherwise, dry weather is expected through Thursday before a
backdoor cold front will bring some showers and thunderstorms late
Friday into Saturday. In the meantime, much above normal
temperatures are expected through the week with the warmest
temperatures expected on Thursday when highs are expected to climb
near or above 90 degrees.
&&
.NEAR TERM /THROUGH THURSDAY NIGHT/...
As of 1015 PM EDT Wednesday...No changes were needed with this
update. As expected, temperatures have cooled since sunset, and
now are generally in the 60s to around 70. Given trends from
last night, lows in the 50s to around 60 still seem reasonable.
The latest HRRR and RAP guidance continues to indicate the
potential for near-surface smoke late tonight/early Thursday
morning; otherwise, clear skies and light winds will prevail
tonight.
Previous discussion...Temperatures will be mild again tonight
with lows reaching only the mid-50s to lower 60s F, staying
especially warm in the Champlain Valley due to light southerly
surface winds, and 925mb temps could be as high as 21-23 C during
the coolest portion of the night. Outside of conditions near 10
degrees above average, some of the smoke from Nova Scotia wildfires
is anticipated to return to the Champlain and lower Connecticut
River valleys tonight, trapped under an inversion in the atmosphere.
It should be fairly similar to last night/this morning, where people
may be able to smell the smoke and see the smoke close to the
surface, but it wouldn`t cause widespread visibility issues. For air
quality information, see the EPA`s air quality index site.
Mild temperatures tonight will help spring temperatures higher
than we`ve seen so far this year, likely breaking records across
the forecast area. Highs will be in the upper 80s and lower 90s
F as 925mb temps soar into the 24-26 C range as high pressure
to our west advects in hot air from the north/west, a notably
unusual place to advect in hot air. We continue to expect
relative humidity to be low, perhaps in the 20-30% range for
most, allowing for a dry heat. Fortunately for fire weather
though, northwesterly winds will be below concerning thresholds.
Regardless of dry heat vs. humid heat, temperatures of this
magnitude can be dangerous for those working or playing outside
and in the sun, and proper precautions are needed.
Thursday night could be even milder than tonight as all that heat
during the day struggles to leave the earth and atmosphere,
especially with potential clouds ahead of our next backdoor cold
front, discussed further below, and moisture increases. Lows in the
upper 50s to low and even mid-60s are expected with calm or light
winds. Some slight chances start arriving in the Northeast Kingdom
late Thursday night/early Friday morning, but anything of note will
be in the short term period below.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
As of 342 PM EDT Wednesday...Friday will be the last of the hot days
before temperatures noticeably cool down Saturday after a frontal
passage. Ahead of the front on Friday, we`ll see some subtle cold
air advection and an increase in humidity and cloud cover. The
slightly cooler air mass along with scattered clouds will prevent
temperatures from climbing quite as high on Friday as what we`ll
have seen on Thursday, though hot conditions are still expected with
high temperatures in the mid to upper 80s. A few of the hotter
locations in the Champlain Valley and Connecticut River Valley may
again reach into the low 90s. The bigger difference on Friday will
be the noticeable increase in humidity/mugginess with dewpoints
forecast to climb into the low 60s. Overall will feel quite muggy,
especially after the recent drier air mass that has been in place.
With the high temperatures and increasing humidity, also
expecting increasing instability over the area that will support
the development of some afternoon showers/thunderstorms. Best
chances for these showers/storms will be over the higher terrain
of the northern Adirondacks and Greens. 0- 6 km shear values
are quite low during the day on Friday, so any thunderstorms are
not expected to be severe.
For Friday night, we`ll see a backdoor cold front drop southward
though the area. Some scattered showers/thunderstorms will continue
into the night as the boundary moves through and just enough MUCAPE
will be present to keep thunderstorms in the forecast through the
night. Any thunderstorms that continue into the overnight hours
should be elevated above a low-level inversion, so again no severe
threat. The better cold air advection won`t occur until Saturday,
so overnight lows Friday night will still be seasonably warm in the
50s.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 342 PM EDT Wednesday...Widespread showers and thunderstorms
will come to an end Saturday morning as the back door cold front
pushes south of our area. Throughout the day Saturday, a shortwave
in the upper-levels will close off over our forecast area, becoming
an upper-low that will gradually drop southward through the weekend.
Under the upper-low, expect cloudy and much cooler conditions with
weekend highs only in the 60s to around 70. Lows will be in the 40s
to around 50. As mid- level lapse rates steepen with the upper-low
moving overhead, expected some isolated to scattered instability-
driven showers during the day on Saturday.
The precipitation forecast from Sunday onward is a little less clear
given the uncertainty in timing of the departure of the upper low,
and potential phasing of the low with additional shortwaves dropping
down from the north. However, the development of an omega block
over the United States will keep troughing in some form anchored
over our area, which will result in continued cooler and unsettled
weather going into next week.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Through 00Z Friday...VFR conditions to prevail at all sites
through the TAF period, with KSLK the lone exception. Much like
last night, brief MVFR/IFR will be possible at KSLK in patchy
fog 08z-11z. Otherwise, SKC expected through the period. Some
surface smoke could also travel up the Champlain Valley again
tonight, but it is not expected to impact the TAF sites or
reduce visibility. Winds will be light/near calm overnight, then
picking up out of the north/northwest around 5 kt after 13z
Thursday.
Outlook...
Thursday Night: VFR. NO SIG WX.
Friday: VFR. Chance SHRA, Chance TSRA.
Friday Night: MVFR/IFR conditions possible. Chance SHRA, Chance
TSRA.
Saturday: Mainly VFR, with areas MVFR possible. Chance SHRA.
Saturday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.
Sunday: VFR. Slight chance SHRA.
Sunday Night: VFR. Slight chance SHRA.
Monday: VFR. Chance SHRA.
&&
.CLIMATE...
New daily records may be set at most if not all climate sites
below over the next few days:
Max Temp Records
Date KBTV KMPV K1V4 KMSS KPBG KSLK
05-31 91|2013 87|2013 89|2013 90|1999 92|2013 87|2013
06-01 90|2013 88|2013 90|2013 87|2018 90|2013 87|1920
06-02 89|1970 84|2013 88|2013 87|1996 87|1990 90|1919
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Storm
NEAR TERM...Hastings/Storm
SHORT TERM...Duell
LONG TERM...Duell
AVIATION...Hastings
CLIMATE...Kutikoff
Area Forecast Discussion
National Weather Service Dodge City KS
1045 PM CDT Wed May 31 2023
...Updated Aviation...
.SHORT TERM...(This evening through Thursday night)
Issued at 120 PM CDT Wed May 31 2023
Main focus over the next 36 hours will be chances for strong to
severe thunderstorms tonight.
Subtle upper waves embedded in a weak flow will move out of New
Mexico into the West Central High Plains this afternoon. A more
significant upper level system that will be associated with the
left exit region of an 250mb upper level still if forecast to
approach southwest Kansas by early evening. Although any of the
subtle upper waves during the day may trigger some afternoon
thunderstorms before 21z today...the main focus for possible
strong to severe thunderstorms from near 00z Thursday through
midnight and will be associated with the upper wave and left exit
region of the upper level jet early this evening. For the
afternoon thunderstorms the RAP was forecasting 20-25 knots 0-6km
shear with 10-20knots 700-500mb flow and dcape 1000 or less. SPC
mesoanalysis at 18z has cin eroding quickly with cu already
starting to develop near this boundary/instability axis. As a
result do expect some isolated to widely scattered afternoon
convection and a few of these storms may also be capable of
producing isolated wind gusts in excess of 50 mph, lightning and
heavy rainfall. After 21z today the focus will shift to extreme
southwest Kansas where the better upper level dynamics from the
left exit region of a 250mb jet, a surface boundary and low level
moisture return will be located late today/early evening. These
thunderstorms that do develop in this area late today and early
tonight will have a better chance to become strong or severe given
that these storms will be moving into an area of more unstable
air with little to no cap. Large low level lapse rates, weak flow
aloft and high preciptable water values. This would support wind
gusts up to 60 mph along with heavy rainfall and isolated hail
will be possible from the strongest storms.
The opportunity for precipitation persists on Thursday, driven by
the progression of the next upper-level trough within the
southwesterly flow, originating from New Mexico and advancing into
the West Central High Plains. Throughout the day, showers and
thunderstorms are projected to propagate across southwest Kansas
as this subsequent upper wave nears from the southwest. The
primary hazards associated with these storms will be lightning and
intermittent episodes of moderate to heavy rainfall.
.LONG TERM...(Friday through Wednesday)
Issued at 120 PM CDT Wed May 31 2023
Key Message in the later periods will be the potential for heavy
rainfall and possible water related issues Friday through Sunday.
From Friday through the upcoming weekend, an upper level
deformation zone will gradually move into and establish itself
across southwest Kansas. This movement coincides with a 500mb high
shifting from the Western Great Lakes Region into the Plains.
This deformation zone will serve as the focal point for ongoing
precipitation chances from Friday through early next week given
the presence of a moist environment and the intermittent influence
of multiple weak waves within this flow, which will enhance lift
in the region periodically.
In addition to the daily precipitation potential...water issues
may end up being the main concern from Friday through Sunday. This
concern is supported by the agreement among the ECMWF and GEFS
ensembles regarding the general location and duration of the
deformation zone which is where ongoing rainfall will likely
occur, the majority of QPF clusters from 00z Sunday through 00z
Monday highlighting the same locations over multiple days, as well
as the agreement on past 24-hour trends indicated by the ECMWF
Extreme Forecast Index and Shift or Tails and above normal
precipitable water values . All this is increasing confidence for
the risk of the possibility of localized flash flooding.
Individuals with weekend plans should be prepared for the
possibility of widespread rainfall, which may lead to some water
related issues in certain areas.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1045 PM CDT Wed May 31 2023
Radar imagery at 0340z indicated numerous showers and
thunderstorms from EHA to LBL, and across the Texas panhandle, all
lifting slowly northward. Some of this activity will impact the
LBL terminal over the next few hours and included a convective
TEMPO group to cover. To varying degrees, models forecast rain
showers and embedded thunder to move northeast across SW KS
through 12z Thu. Included VCTS/CB/VCSH wording only, with very low
confidence on impacts on any specific airport. Outside of any
convection, VFR will continue to prevail through this TAF, with
mid level cloud decks prevailing. Light winds will continue
through 15z Thu, again outside of convective outflows. After
15z Thu, south winds will increase at all airports, gusting
25-28 kts. Scattered convection is expected to redevelop after
18z Thu, but only included a VCTS/CB mention for now.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 60 76 59 79 / 30 40 40 50
GCK 58 77 58 78 / 30 40 60 40
EHA 57 73 57 79 / 60 50 50 30
LBL 58 76 58 80 / 30 50 60 40
HYS 62 78 60 82 / 30 40 50 70
P28 65 78 62 81 / 30 40 30 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Turner
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
647 PM CDT Wed May 31 2023
...Aviation Update...
.DISCUSSION...(This evening through Wednesday)
Issued at 301 PM CDT Wed May 31 2023
Key Messages:
* Chances for isolated/scattered storms will continue into this
evening/tonight across the area...and while some storms could be
on the strong side with gusty wind/small hail/heavy rain, the
overall threat for severe weather is low.
* Off-and-on thunderstorm chances remain in the forecast through
the weekend and into early next week...with the best overall
chances looking to be Thursday-Saturday. Could be drier Sunday-
Wednesday, but plenty of uncertainties remain.
* Not looking at any notable swings in high temperatures,
remaining mainly in the 80s through the forecast...but changes
in precipitation chances could affect those highs.
Currently through tonight...
Upper air and satellite data continue to show a fairly light flow
pattern in place across the region today...flow is generally
southerly, with areas of low pressure over the Desert SW, Gulf Coast
region and northeastern CONUS. Overall it`s been a dry day, though
some isolated activity has developed in the last hour or so, just
barely clipping far eastern portions of the CWA. Any upper forcing
is subtle at best, but looking at SPC Meso page it`s an area with
little/no CIN and in axis of higher instability (~2000 j/kg MLCAPE).
Can`t rule out some additional activity late this afternoon, but
along with forcing being weak, mid-level lapse rates aren`t great
and deeper layer shear is on the low side...so while a few storms
could be on the stronger side at times, overall threat for severe
storms remains low.
Additional thunderstorm activity has developed off to our west over
the High Plains, driven by shortwave upper level forcing, sfc
troughing and peak heating. For the most part, models are not
showing great chances of a notable amount of that activity making it
this far east overnight...with our chances looking to be more
scattered in nature and aided by the LLJ. Kept PoPs on the lower
side, in the 20-40 percent range...they`re likely too broad in
nature, but with plenty of difference in models, hard to completely
rule out any particular areas. Similar to this afternoon and
evening, elements needed for a more organized severe weather threat
are lacking...but some gusty winds/small hail/heavy rain will remain
a possibility.
Thursday into early next week...
As far as preciptiation chances go, unfortunately, it`s a pretty low
confidence forecast for mid-week on into the start of next week,
with plenty of differences continuing between models. Looking at
Thursday through Saturday, NBM continues with CWA-wide PoPs through
each day, but it`s not looking to be a 3-day washout...just enough
uncertainties/spread in model solutions to be able to focus in on
any one particular area/time frame to rule out chances. Driving
those daily PoPs is the continued Rockies/western CONUS broader
troughing, and any shortwave disturbances that get ejected out
ahead. For the most part models have favored the mid-late afternoon
and evening/overnight for the main chances for storms, but there is
even some uncertainty with that for tomorrow/Thursday, some models
show the better chances being morning through mid-afternoon and then
a lull...others have chances never totally gone through the
afternoon. It`s a frustrating pattern for sure. As far as severe
weather goes, models still showing a generally modest CAPE/lower
shear environment...and the CWA remains outside of the Days 1-3 SPC
risk areas. Some stronger storms will certainly be possible, but
some things are lacking for a more organized/widespread severe
weather threat.
Models hint at the chance for a drier period late in the weekend-
early next week with the potential for higher pressure/blocking
pattern to develop over the central CONUS...but like any day prior,
lot of uncertainty in the forecast.
Looking at temperatures, the overall trend of highs being above
normal for this time of year looks to continue...with no notable
swings either way expected. Normal highs for this time of year are
in the upper 70s to low 80s...and in general highs look to be the
low-mid 80s. However, with the uncertainties in precipitation
chances, that spills over into and lowers confidence in high
temperatures.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday)
Issued at 645 PM CDT Wed May 31 2023
Generally a low confidence forecast in terms of potential for
convection tonight into Thu. Kept the VCTS that was already in
there after midnight, though latest HRRR trends have been for less
convection overnight. There`s enough convective activity W/SW of
the area that outflow and/or MCVs could kick E and keep chcs
going in presence of elevated instability. Otherwise, expect SCT
CU around 7K ft for a few more hrs, then SCT-BKN mid to high cld
blow off from convection off to the W. Thu looks like another day
with a mix of CU and high clds. A couple models hint at low
stratus Thu AM, but given other uncertainties have left it out
attm. Wind will be SE to S 5-10kt tonight, then incr to 10-15kt,
gusting up to 25kt for daytime hrs Thu.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
DISCUSSION...ADP
AVIATION...Thies
Area Forecast Discussion
National Weather Service Grand Junction CO
546 PM MDT Wed May 31 2023
.SHORT TERM...(Tonight through Thursday night)
Issued at 300 PM MDT Wed May 31 2023
Showers and thunderstorms have fired this afternoon with plenty of
coverage seen across the CWA. As expected, those drier subcloud
layers have allowed some gusty outflow winds to materialize. A
stronger cell near Durango caused a 50 mph gust at the airport
but, by and large, most gusts have been spread between 35 to 45
mph. CAM guidance has picked up on the location and intensity of
this convection fairly well and they show convection continuing
through the early evening hours before subsiding. Of note, the
NAMNEST is picking up on another line of showers moving from the
Four Corners up into the Grand Valley around midnight while the
HRRR does show some activity in the same area but nowhere near as
robust. Might see a few showers, a rumble of thunder or two, or
maybe just some clouds...it`s that kind of environment.
Thursday, look for more of the same as the low pressure will be
over the Four Corners region. The added lift from the low will
work on the available moisture and increased instability will
further aid in convective development. Those areas not seeing
convection will see plenty of cloud cover and thus, lower high
temperatures. This trend will continue into the weekend.
.LONG TERM...(Friday through Wednesday)
Issued at 300 PM MDT Wed May 31 2023
Very little change noted from previous model runs with regards to
the long term period. The closed low will open up as it moves across
the CWA and eventually stalls on top of Colorado. Plenty of moisture
and instability will allow showers and thunderstorms to form each
afternoon and evening heading into the weekend. As previously
mentioned, this area of low pressure will basically dissolve in
place as a retrograding downstream high pressure cell creates a
strong omega block over central NOAM by early next week. This
extremely amplified pattern persists into the middle of next week
and is so anomalous that the models are struggling to find agreement
in many areas. The basic flavor of the forecast remains daily
afternoon showers and thunderstorms becoming fairly widespread
through the weekend with lingering isolated convection during the
overnight hours.
Monday onwards, there will be no focus, per se, for convection aside
from lingering moisture and daytime heating. Even so, it will be
enough for convection to fire though coverage should lessen some
from what was seen over the weekend. As we`ve said for the last
several days, the finer details are still just not there but there
is high confidence in widespread showers and storms. As one would
expect, high temps will run below normal thanks to increased cloud
cover and the precip. Sure doesn`t seem like June...
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 541 PM MDT Wed May 31 2023
Scattered showers and thunderstorms will continue to fire along
the terrain of western Colorado and eastern Utah this evening.
Some of these showers will be capable of producing strong outflow
gusts and brief IFR visibilities with rainshowers. Convection will
tamp down after sunset and mostly quiet conditions will prevail
from midnight into the morning hours across the region. Shower
activity will develop again Thursday morning and continue through
the afternoon over the region. Showers and storms will develop on
the terrain again and drift out over the valleys, bringing strong
outflows, brief torrential rain, lightning, and small hail.
&&
.HYDROLOGY...
Issued at 300 PM MDT Wed May 31 2023
No major changes in terms of hydrologic conditions today. Warm
temperatures the last several days have helped accelerate snowmelt
across high elevations, and narrowed the extent of snow left over
mid-elevation zones. In general, the season`s daily peak in flow
typically coincide when these two elevation zones dwindle in unison.
However, the oscillating temperatures this spring have mitigated the
rate of snowmelt across the board, so far this year. As a result,
the originally expected peaks are trending down. Instead, prolong
periods of high water and fast flow have been observed and are
expected to continue across much of the West Slope.
Weather shifts in the coming days, towards a cooler and wetter than
normal pattern. In terms of temperature, the rate of snowmelt will
slow, decreasing the risk of a high spike along rivers and streams.
On top of that, cooler mountain peaks (mainly above 10,500 ft) could
accumulate several new inches of snow in this moist regime, which
would just add to the delayed mountain season. In contrast,
precipitation in the form of rain (heavy rain) falling on snow would
enhance snowmelt processes. So in summary, the variance in the
weather over a given basin in the coming days translates to a level
of uncertainty in river forecasts, as spring runoff is highly
dependent on spring weather. In general, though, forecast
hydrographs are trending down through the weekend, which would
reflect a cool regime and reduced snowmelt. Though, the caveat,
convective processes may not be captured. Training storms focused
over one basin could lead to instantaneous spikes in flow, or end
becoming the daily peak we`ve been anticipating.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...None.
UT...None.
&&
$$
SHORT TERM...TGR
LONG TERM...TGJT
AVIATION...LTB
HYDROLOGY...ERW
Area Forecast Discussion
National Weather Service Grand Rapids MI
721 PM EDT Wed May 31 2023
LATEST UPDATE...
Aviation
.SHORT TERM...(This evening through Thursday night)
Issued at 328 PM EDT Wed May 31 2023
Visible satellite imagery shows an extensive cumulus field over much
of Lower MI, with pockets of more vigorous cumulus congestus over
the northern half of Lower MI, where recent reflectivity returns and
lightning strikes are noted. RAP mesoanalysis depicts a plume of
drier air at 850 mb encroaching on Lower MI from the east, along the
southern edge of the high over eastern Ontario. The entrainment of
this drier air into the boundary layer is likely contributing to
lower surface dewpoints over parts of southeast Lower MI, with a
corresponding NW-SE gradient of surface-based instability across the
Lower Peninsula. Away from this dry air, RAP guidance suggests that
appreciable surface-based instability is present over the northern
half of the forecast area, with MLCAPE of 1000-1500 J/kg. This
instability likely extends to areas slightly west of the advancing
lake-breeze boundary, where onshore low-level trajectories have
undergone sufficient warming. Another area of surface-based
instability is present over northern IN, with MLCAPE of around 500
J/kg.
Through this evening, CAM guidance suggests that isolated to widely
scattered showers/t-storms are most favored north of a line from
roughly Fremont to Clare, with additional convective initiation
likely to be aided by low-level convergence along the lake-breeze
boundary. Convective organization will be constrained by weak 0-6 km
bulk shear (10 kts or less). However, inverted-V thermodynamic
profiles beneath the CCL will contribute to sizable DCAPE (800-1200
J/kg) through early evening. In this environment, locally gusty
outflow winds are possible with isolated/pulse storms that develop.
Storms through this evening will tend to drift slowly northward,
approximately with the 0-6 km mean flow.
A broadly similar environment will remain in place on Thu. However,
the eastward extent of instability across the forecast area is
questionable (e.g., in 15z RAP guidance), likely owing to the
continued influx of dry air near 850 mb. Slight chance PoPs will be
carried across the western half of the forecast area, as supported
by HREF probs.
.LONG TERM...(Friday through Wednesday)
Issued at 328 PM EDT Wed May 31 2023
Friday still appears to be the warmest day in this stretch with
H8 temps near 20C underneath the upper high and would not be
surprised to see a few highs up around 95. Convective
threat/coverage expected to be very limited or non-existent
Friday due to drier air mass and presence of greater CIN related
to the warmer temps aloft.
Retrograding upper high and development/evolution of an east
coast longwave trough should lead to gradually cooler air
filtering in from the northeast-- especially Sunday through
Tuesday-- although ensemble temp spread increases in these
periods.
Low level northeast flow will deliver lower sfc dew points to the
area once again for the first half of next week, with 40s likely
and 30s even possible. Will need to monitor wind speeds as
critical fire weather parameters could be reached. The lower dew
points will obviously keep rain chances quite low (less than 20
pct), so the dry conditions will only worsen.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 721 PM EDT Wed May 31 2023
VFR conditions will continue through Thursday evening. Only
scattered afternoon cumulus with bases AOB 7000 KFT AGL are
expected on Thursday.
&&
.MARINE...
Issued at 328 PM EDT Wed May 31 2023
Winds in the nearshore waters will continue to be driven primarily
by the diurnal land-breeze / lake-breeze circulation. Through Thu
afternoon, guidance suggests that these winds will likely remain
rather light. On Fri and Sat, models suggest that a broad surface
ridge will become established west of the region. This synoptic-
scale regime should favor a somewhat stronger lake-breeze
circulation on Fri and Sat afternoons, yielding N or NNW winds in
the nearshore zones. Given the possibility of stronger winds and
greater fetch, conditions may necessitate a SCA and Beach Hazards
Statement (high swim risk) as early as Fri afternoon, with a
somewhat greater chance of hazardous winds/waves on Sat afternoon.
Aside from these wind/wave considerations, isolated t-storms are
expected to continue forming inland this afternoon/evening, and
again on Thu afternoon. T-storms through this evening will drift
northward, with a small chance of storms reaching the nearshore
waters from Holland south. T-storms on Thu afternoon will move
slowly northwestward, with a small chance of storms across most
nearshore zones.
&&
.CLIMATE...
Issued at 342 AM EDT Wed May 31 2023
Record High Temps
GRR MKG LAN AZO BTL BIV
Wed 5/31 95-1934 88-2016 96-1895 93-1911 94-1919 92-1934
Thu 6/1 102-1934 88-2014 97-1934 102-1934 100-1934 100-1934
Fri 6/2 95-1934 87-1963 93-1919 102-1934 97-1934 95-1934
Record Warm Lows
GRR MKG LAN AZO BTL BIV
Wed 5/31 73-1937 70-1970 73-2022 71-2022 71-2022 73-1937
Thu 6/1 74-1934 66-1970 68-1970 71-1895 71-1895 75-1934
Fri 6/2 69-2014 66-1949 69-2014 76-1934 72-1934 70-2014
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&
$$
SHORT TERM...Kenyon
LONG TERM...Meade
AVIATION...Ostuno
CLIMATE...NJJ
MARINE...Kenyon
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1001 PM EDT Wed May 31 2023
.SYNOPSIS...
Weak high pressure remains over the area through Friday. A weak cold
front drops south across the area Saturday. High pressure returns
for early next week. Another cold front will arrive from the north
by the middle of next week.
&&
.NEAR TERM /THROUGH THURSDAY/...
As of 950 pm EDT Wednesday: Isolated late evening showers continue
mainly in upslope-enhancement and convergence regions along the
eastern slopes of the mountains, and also east of the I-77 corridor
where modest Atlantic moisture has wrapped west from the offshore
low center. Anticipate the eastern showers battling with some degree
of drying on northeast flow overnight to generally dissipate with
time. Mountain coverage should gradually become sparser as well with
the loss of daytime instability and weakening flow. The area should
be mostly free of light rain showers after midnight. The combination
of patchy high clouds, lingering stratocumulus in various layers,
and spotty lower stratus on the northeast flow should keep partly
cloudy conditions north to mostly cloudy skies south across the
region overnight. The clouds and dewpoints mostly in the lower 60s
will keep minimum temperatures from falling much below current
values. Still anticipate low cloud and fog development in the
mountain valleys where boundary layer moisture persists, but with
most guidance not depicting much dense fog.
Northeasterly 850 mb flow will alternately bring morning drying on
Thursday followed by a brief uptick in Atlantic moisture during the
afternoon. Instability continues to look quite limited in all but
the far western mountains and this should confine isolated to
scattered weak convective coverage primarily to the mountains.
Cannot rule out a few rogue showers making a run westward into the
Piedmont in a few bands of arriving Atlantic moisture, but with any
showers encountering drier profiles and dewpoints near the I-77
corridor. With less in the way of morning stratus, temperatures
should rebound closer to climatology for the first of June.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
As of 158 PM EDT Wednesday: Generally shallow instability in the
mountains, and nonexistent instability elsewhere, will give way to
quiet conditions going into Friday night. The pattern at this point
will remain dominated by a broad surface high over the upper Mid-
Atlantic, which will maintain easterly flow and at least some
moisture flux into the area through Friday evening. This will
result in cloudy, though generally dry, conditions across the area
on Friday, beneath weak forcing aloft. Apart from a few pop-up
thunderstorms over the mountains, there`s generally little to talk
about. Temperatures will be around normal.
By Friday night, as a surface low drifts up the Atlantic coast, flow
over the Carolinas will take on an increasingly northerly
component...which will cut off the better moisture. Thus, despite
some measure of clearing, instability actually looks more anemic (if
that`s even possible) on Saturday and virtually no thunder chances
will be carried into the new forecast package. Temperatures will
continue to rise, reaching solidly-above-normal values by Saturday
afternoon.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 215 PM EDT Wednesday: Oh what a challenge it has been to gain
steady insight into the synoptic pattern for the end of the weekend
and next week. As noted by the previous forecaster, the pattern
does look to become more amplified by Sunday, but it remains unclear
exactly how that will play out since each guidance source is off in
its own little world. The CMC and ECWMF are in decent enough
agreement through Sunday night, depicting a fleshed-out upper low
off the New England coastline...which remains too far north and east
of the forecast area to promote much moisture or synoptic forcing in
the Carolinas. This would promote some isolated to widely scattered
low-end diurnally-forced convection...but little else. And granted,
the 06z and 12z GFS cycles are showing this as well...it`s just that
where the other guidance keeps this feature to our northeast, the
GFS (and the majority of its ensembles, for what that`s worth)
depict some retrograde motion of the low, westward into the Ohio
Valley through Monday. Were this scenario to play out, it`d pretty
strongly enhance the dynamical forcing over the Carolinas by by
Monday afternoon, and more active weather could be in order. I like
to imagine the GFS as similar to an 80s-style action movie villain:
sitting in its dark lair laughing, its intentions unclear and yet
definitively at odds with everyone else. In the case of 80s movies,
of course, this typically resulted in various popcorn-worthy action
sequences...while in the case of the GFS, the "villainous" solution
would just result in far better convective potential than what the
rest of the guidance favors.
Regardless of which solution plays out for Monday...most of the
guidance depicts some flavor of shortwave rotating across the Mid-
Atlantic on Wednesday, though impacts will hinge on timing and
intensity of this feature, which at this point is about as clear as
mud. Temperatures will fall a little below normal for Monday (maybe
a lot below normal if the GFS`s deep-upper-low solution pans out)
before rebounding to at least a category above normal by Wednesday.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: Varying VFR bases are evident this evening,
with areas of high clouds, lingering high-based stratocumulus, and
persistent patches of lower VFR cumulus showing up on satellite
imagery and in observations. Low-level northeast flow could bring in
some patchy MVFR-level clouds from an Atlantic moisture source, but
even the most aggressive RAP has backed off on this for the
overnight hours, with other solutions tending toward drier 950 to
850 mb flow. Will keep VFR conditions through the night across the
foothills and Piedmont, but feature some SCT020 to hint at lower
bases. Restrictions could be a bit more widespread in the mountain
valleys and around KAVL overnight where the boundary layer moisture
has been most persistent. Will feature a window of IFR conditions
around daybreak at KAVL. VFR stratocumulus or cumulus bases will
then return with heating on Thursday. SHRA/TSRA chances will be best
in the mountains, but generally stay modest around KAVL. Expect NE
winds through the period except for southeast flow at times at KAVL.
Low end gusts will be possible throughout with mixing Thursday
afternoon.
Outlook: Isolated SHRA/TSRA and associated restrictions appear
possible in and near the Appalachians again on Friday afternoon.
Shower chances may rise modestly over the weekend as a backdoor cold
front settles south through the region. The easterly flow regime
should get reinforced over the latter half of the weekend and linger
into early next week.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...DEO
NEAR TERM...HG
SHORT TERM...MPR
LONG TERM...MPR
AVIATION...HG
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
610 PM CDT Wed May 31 2023
.SHORT TERM... (Through Late Thursday Night)
Issued at 224 PM CDT Wed May 31 2023
Above normal temperatures and precipitation chances will be the main
focus through Friday.
The broad area of showers and thunderstorms over western Missouri
and eastern Kansas has since collapsed. Visible satellite shows
variable cloud cover surrounding a remnant MCV pushing from eastern
Kansas into western portions of Missouri. Ahead of the MCV is an
elongated area of surface to mid-level convergence that has
supported showers and a few thunderstorms over central Missouri.
Latest guidance tracks the MCV more north than east late this
afternoon into this evening, also aiding to shunt the convergent
feature into northeast Missouri by sunset. Surface dewpoints in the
60s, MLCAPE values in the 1,000-1,500 J/kg range and mid-level lapse
rates of 6.5-7C will be plenty of support showers and thunderstorms
as lift is provided by the MCV moving north-northeast into Iowa
through late this evening. Shear has been a big limiting factor with
10-15 knots depicted in RAP soundings through the depth of the
modeled environment. While nothing is expected to be well-organized,
PWATs around 1.5-1.7 inches will make efficient rain producers with
localized heavy rainfall possible with the best potential over
central and northeast Missouri through about 02z this evening. PoPs
have been trimmed (15-20 percent) over eastern sections of the CWA
with little more than near-1,000 J/kg MLCAPE values and 60 degree
dewpoints supporting isolated activity.
The envelope of lower dewpoints (50s) that essentially separate the
western and eastern sections of the CWA today will give way to an
expanding field of moisture with dewpoints rising into the 60s
across the entire forecast area. Though the potential for showers
and thunderstorms broadens in area, the chances themselves are not
impressive. Limitations are similar to today with weak shear and the
absence of an organized system nor convergent feature. That said,
any development could result in localized heavy downpours and
outflow boundaries that lead to downstream, sporadic convection,
mainly through the diurnal peak.
Friday once looked to be the day for broader convection. However,
latest indications show a quicker influence from easterly flow
around the strengthening ridge to the north. NBM probabilities (40-
60 percent) are likely too high and may trend downward in time if
latest guidance is any indication of trends to come. This is
especially true at the eastern fringes of the potential (east of the
Mississippi River).
Nighttime periods will likely see lulls between diurnally driven
daytime convection. Temperatures will largely be uniform in nature
with 80s covering the entire CWA and a few 90s in relatively warmer
locations. The one caveat will be localized rain-cooled due to
afternoon convection. Outside of that, temperatures will run
approximately 10 degrees above normal.
Maples
.LONG TERM... (Friday through Next Wednesday)
Issued at 224 PM CDT Wed May 31 2023
The potential for showers and thunderstorms will wane this weekend
as upper level ridging retrogrades through the Upper Midwest and
stations itself over south central Canada. This ridge is expected to
be anomalously strong, with both the NAEFS and ECMWF ensembles
showing 500 mb heights above the climatological maxmimum near the
peak of the ridge. As the ridge climbs northwest, an upper level low
will be retrograding to the southwest through southeast Canada and
New England. This will force deep dry air into the region over the
weekend, cutting off our chances at rainfall.
A backdoor front will pass through the Mid-Mississippi Valley
Saturday morning in response to the change in pattern. East-
northeasterly winds will follow, accompanied by the aforementioned
dry air. Temperatures will remain above average, with Saturday
actually forecast to be the warmest day of the next seven. Clear
skies and dry low levels will result in efficient mixing, allowing
18 to 20C 850 mb temperatures to reach the surface. This is expected
to translate to highs Saturday afternoon in the mid-90s. These
temperatures are encroaching upon record territory, with KUIN
currently the closest climate site to reaching or exceeding their
previous record of 92 degrees set in 2011. KSTL (96/2011) comes
within a degree as well, but KCOU will likely remain just out of
reach (97/1911).
The upper level low in the eastern CONUS will meander around that
region of the country before deepening and expanding early next
week. This will place the Mid-Mississippi Valley in northwest flow
aloft on the backside of the trough, an area not conducive for
beneficial rainfall. Ensemble guidance supports this, with over half
of the members of the ECMWF, CMC, and GEFS combined showing no
rainfall, and the majority of the rest showing less than 0.5 inches
through next week. Although the next week looks dry, the Climate
Prediction Center outlook for June 7th through June 13th shows some
optimism with precipitation probabilities leaning above normal for
the southern CWA. The seasonal (June-July-August) precipitation
outlook also highlights our CWA with above average probabilities.
Hopefully this means the rest of the spring and summer won`t be as
dry as the beginning.
Jaja
&&
.AVIATION... (For the 00z TAFs through 00z Thursday Evening)
Issued at 608 PM CDT Wed May 31 2023
Isolated showers and weak thunderstorms should slowly wane and
dissipate through late this evening. Current activity is east of
central Missouri sites and west of KUIN and metro St. Louis so no
terminal is likely to be impacted by this activity. Dry/VFR
conditions forecast overnight tonight into early Thursday with
light southeasterly winds. Coverage of showers and weak
thunderstorms may be a bit higher and more expansive tomorrow, but
confidence is low overall in terms of where activity may be more
focused than others. Given that, went with a VCSH group for now
beginning in the mid/late afternoon.
Gosselin
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Marquette MI
1138 PM EDT Wed May 31 2023
.SHORT TERM...(This afternoon through Tonight)
Issued at 235 PM EDT WED MAY 31 2023
Today has been another very warm day in the Upper Peninsula, we hit
90 degrees breaking the record high temp of 88 degrees previously
set in 1988 here at the WFO! RAP analysis shows high pressure over
New England with a sfc low and mid level trough over northwestern
Ontario. This sets up southerly flow near the surface and aloft that
continues to bring highs this afternoon well into the 80s with some
seeing low 90s. Dew point temps have been slightly higher than
yesterday, however the elevated fire potential remains through the
afternoon with the warm temps, winds gusting up to 15 mph, and the
RHs settling into the Upper 20s/low 30s before dew point temps can
recover this evening. Bufkit soundings indicate no real layers of
moisture, but the CAMS still are indicating some spotty shower
development over the west half of the CWA. CAPE has already reached
into the 500-1000 J/kg range and the model soundings yield some
values late afternoon/evening into the 1000-1500 J/kg range.
Radar/satellite imagery already show some cumulus development, which
will continue mainly over the central UP, but I am fairly confident
that the dry air will win against any potential shower development
preventing anything from reaching the ground until this evening or
tonight (if at all in this forecast period).
This synoptic pattern will continue through tonight continuing the
mostly dry weather outside some possible showers over the far west.
With a similar pattern to last night, I kept low temps in the 50s
with warmer temps, possibly in the low 60s, along the lakeshore
areas. Mostly dry weather will continue outside some slight
potential for showers over the very far west tonight; most likely
any precip chances will stay out over the far west end of Lake
Superior.
.LONG TERM...(Thursday through Wednesday) Issued at 436 PM EDT
WED MAY 31 2023
Above normal temperatures and below normal precipitation are
expected to continue over the next week. There are near-daily
chances of rain across portions of the west half, but any rainfall
that occurs is expected to be localized in nature. The Keweenaw from
Houghton northward and counties east of Marquette/Dickinson are most
likely to stay completely dry.
At the synoptic scale, a 500mb ridge centered over the lower Great
Lakes Thursday morning retrogrades westward to southern Manitoba by
Friday night where it reaches peak amplitude Sunday evening. This
ridge gradually decays next week as troughing along the Atlantic
Coast amplifies resulting in increasing northerly flow aloft across
the UP. Low level flow backs from warm/moist southerlies on Thursday
to southeasterly flow Friday then drier easterly flow behind a weak
cool front on Saturday. A more pronounced cool front moves through
late Sunday with a longer-lasting period of dry northeasterly flow
early next week. The warmest temperatures are expected downwind of
the prevailing wind direction each day with another warm day along
the Lake Superior on Thursday, converging lake breezes Friday and
Saturday, then another day near 90F across the interior west on
Sunday. Assuming the cold front comes to pass, Monday and Tuesday
look 5-10F cooler with mid 70s to low 80s areawide, coolest near
Lake Superior.
Regarding precipitation chances, recent HREF guidance has
persistently highlighted the area between Ironwood and L`Anse
tomorrow aftn/evening. Confidence is high (>70%) that a few storms
will initiate there, but spotty coverage caused me to cap PoPs
around 50%. CAMs highlight MLCAPE values approaching 1500 J/kg with
bulk shear values near or below 20 knots suggesting a pulse storm
mode. There were a few reports of pea-dime-nickel size hail to our
south today in a similar environment and I wouldn`t be surprised to
see that threat materializes again with the strongest storms
tomorrow. The threat should be brief/localized before the storms
rain themselves out, but additional activity may pop up along a
southeastward propagating outflow boundary before instability
diminishes in the evening.
Friday also has a relatively high probability of isolated
afternoon/evening thunderstorms. The upper level ridge axis moves
overhead during the day resulting in a noticeable wind shift across
the lake. This should allow for a more robust afternoon lake breeze
and global models suggests MLCAPE values could approach 2000 J/kg
along the boundary, but bulk shear values are even lower (AoB 10
kts) suggesting a lower threat for small hail. Saturday is probably
the best chance for the eastern UP to get any rainfall with light
easterly flow resulting in converging lake breezes, but shear
remains AoB 10 kts. An upper level vort max associated with a
frontal boundary pushing northeast to southwest across the area
could locally enhance precip too. Much drier air moves in behind the
front for Sunday allowing precip chances to return to zero, but
light winds preclude a more substantial fire wx threat.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1137 PM EDT WED MAY 31 2023
VFR will continue with mid-level ridging holding strong over Upper
Michigan. Winds will be light and generally southerly, except at
CMX where there is an easterly component. Chances will be better
later today for pop-up showers and thunderstorms, but confidence is
too low at this point in regard to location and timing to insert
mention at any one TAF site.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 436 PM EDT WED MAY 31 2023
With mid-level ridging over the region for a majority of the
forecast period, expecting winds of 20kts or lower across the lake
through the weekend. Thunderstorms are possible each day through at
least Saturday, mainly across the western half of Lake Superior.
Very stable conditions over the lake and the lack up any low level
jet features to force elevated storms suggests any activity should
be confined to the ports and nearshores. Severe storms are not
expected, but a few storms capable of small hail are possible during
the afternoons and evenings.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Jablonski
LONG TERM...EK
AVIATION...TDUD
MARINE...EK
Area Forecast Discussion
National Weather Service New York NY
1135 PM EDT Wed May 31 2023
.SYNOPSIS...
High pressure will remain in control but will be slightly
weakening across the local area Thursday night into early
Friday. A backdoor cold front is expected Friday night/Saturday
morning with low-pressure building through the weekend. A
coastal low will impact us Monday-Tuesday. Another cold front
is expected Tuesday into Wednesday.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Forecast remains on track with only minor adjustments to
temperature and dew points to reflect the most recent
observations and trends.
Mostly clear sky conditions initially along with decreasing
winds has allowed for radiational cooling. With light onshore
flow along the coast, expecting for the development of low
clouds and fog. Some of the fog could become dense, especially
further east.
Forecast lows range from upper 40s to upper 50s using a blend of
the NBM and its 50th percentile. This is relatively warmer for
the coastal areas due to the abundance of low clouds and fog as
well as light onshore flow.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
For Thursday, the morning low clouds and fog will get scoured
out with diurnal heating and vertical mixing in the boundary
layer. The fog and low clouds shift south of Long Island and
dissipate, with a mostly sunny day expected.
Winds are pretty light but increase in the afternoon with sea
breeze development.
Used a combination of MAV MOS, MET MOS, NBM and consensus of raw
data for forecast highs Thursday ranging from low 70s across SE
CT and Eastern LI to upper 80s within parts of NE NJ and Lower
Hudson Valley. This combo keeps cooler temperatures along the
coast compared to MOS and NBM.
For Thursday night, similar fog and low cloud development
forecast to redevelop along the coast with slight increase in
dewpoints. Otherwise, mostly clear sky conditions farther north
and west across the interior. Lows forecast from lower 50s to
lower 60s.
Regarding the patchy smoke, HRRR forecasts this to move back
southeast but at gradually lowering concentrations as it gets
more dispersed.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Stuck fairly close to the NBM through the long term period. Pretty
much every day has a chance of rain in the forecast.
Ridging aloft from the west begins to breakdown on Friday as a
trough drops south from Canada to New England. 850 mb temps warm
into the 16-18C range with surface temps likely reaching the upper-
80s to lower-90s inland with mid/low-80s for coastal areas. A
backdoor cold front is also expected overnight Friday into Saturday
morning. The prefrontal trough will bring PVA and instability
leading to scattered showers and thunderstorms. SBCAPE values are
1000-1500 J/kg from the GFS, but looking higher on the NAM at 2000-
2800 J/kg. Some of the stronger instability occurs inland where
there is also a chance for some possible small hail give colder air
aloft as seen on model soundings.
After the backdoor front passes overnight, we should maintain north
or easterly flow through the weekend with gusting winds 20-25 kts
and maintain it through Monday. High will be much cooler Saturday
thanks to the front, with highs in eastern areas in the mid-60s with
western areas in the low-70s. The trough building in New England
cuts off at upper-levels and slowly retrogrades south and west over
the weekend. The cyclonic flow from this low could lead to daily
shower chances. The lower heights will prevent us from warming up
much through the weekend.
A coastal low riding up the coast will bring more showers for Monday
and Tuesday, also allowing temperatures back into the mid-70s. FROPA
may occur sometime on Tuesday or Wednesday but models do not have a
consensus on timing with this.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
High pressure remains in the vicinity of terminals throughout the
TAF period.
VFR gives way gradually to low stratus/fog from east to west,
bringing IFR to LIFR conditions. Highest probability of IFR and
LIFR is for NYC terminals on east. City terminals more likely to
experience IFR and LIFR conditions after 6z.
Winds go light and variable overnight and will remain light to calm
into early Thu morning. The winds will be mainly SE to S during the
day Thu at 5 to 10 kt.
Smoke from Canadian wildfires could limit visibilities slightly, to
around 6SM at times Thu. Confidence remains low so kept haze and
smoke out of TAFs for the time being.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of onset of IFR and LIFR cigs overnight may be off by up to 2
hours, along with questions as to how far west it gets. Low stratus
and fog may only impact KEWR/KTEB for only an hour or two into early
Thu am.
There remains some uncertainty with how much surface restrictions to
sky/vsby there will be with the haze and smoke on Thursday. For now
keeping haze and smoke out of TAFs, but amendments may be needed on
Thu.
OUTLOOK FOR 0Z FRIDAY THROUGH MONDAY...
Thursday night: Mainly VFR, but chance of IFR or lower with stratus,
with best chance for eastern most terminals.
Friday: Mainly VFR. Low chance of showers/thunderstorms and MVFR,
mainly at night.
Saturday: MVFR possible with a chance of showers throughout the day.
NE-E winds near 10-15kt with gusts near 20-25kt, highest at the
coastal terminals.
Sunday: Becoming VFR.
Monday: VFR to start, then MVFR possible in afternoon showers.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
With a relatively weak pressure gradient remaining across the
local waters, conditions for winds and seas will remain below
SCA thresholds through Thursday night.
Sub-SCA winds and waves expected Friday. SCA conditions expected
on all waters on Saturday with gusts upwards of 30 kt. SCA
conditions then persist mainly on the ocean waters Sunday
through Monday with gusts of 25-30 kts, waves 5-7 feet.
&&
.HYDROLOGY...
No hydrologic impacts expected through early next week.
&&
.TIDES/COASTAL FLOODING...
A moderate rip current risk is expected Thursday and Friday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BR
NEAR TERM...JM/MW
SHORT TERM...JM
LONG TERM...BR
AVIATION...JE
MARINE...JM/BR
HYDROLOGY...JM/BR
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Pendleton OR
434 PM PDT Wed May 31 2023
Updated Aviation Discussion
.AVIATION...00Z TAFs...VFR conditions over the next 24 hours.
Gusty winds remain through 04-08Z all sites. Overnight winds
should then become light and generally 10kts or less. Breezy winds
then possible again tomorrow though not as strong as today,
generally less than 25kts. Skies clear or some CIGs at FEW 20k
feet or higher possible. Goatley/87
&&
.PREV DISCUSSION... /issued 254 PM PDT Wed May 31 2023/
SHORT TERM...Rest of Today through Friday night...Satellite
imagery reveals a sharp gradient in moisture across the forecast
area as a shortwave trough approaches. Dry and mostly clear
conditions are present west of the Blue Mountains while isolated
convection continues across eastern Grant, Union, and Wallowa
counties where just enough instability, moisture, and forcing is
present to support showers. Farther east into Idaho and southeast
Oregon where the environment is more moisture rich, scattered
convection is occurring ahead of a shortwave trough. Most of the
convection across our forecast area has been shallow with the
highest echo tops in the vicinity of 20-25 kft and only isolated
lightning strikes picked up by lightning networks. Convection is
forecast to diminish this evening with mostly dry conditions then
forecast overnight.
Winds through the Columbia River Gorge and Kittitas Valley have
flirted with advisory criteria much of the morning and afternoon,
and sustained winds at DLS and ELN are now just above criteria (30
mph). Observed pressure differences of roughly 5 mb between DLS
and PDX and 8 mb between ELN and SEA have been slightly stronger
than forecast by guidance and are supporting windy conditions.
Pressure gradients and 850 mb winds are forecast to peak over the
next few hours, and the vorticity maximum associated with the
incoming shortwave will cross over the region this evening so
confidence of a few hours this afternoon and evening where
advisory criteria are reached or exceeded at DLS and ELN is high
enough to issue a short-duration Wind Advisory for the Kittitas
Valley and eastern Columbia River Gorge. Winds are then forecast
to slacken below advisory levels overnight and into Thursday
morning.
Hot on the heels of the first shortwave, a second compact, albeit
weak, vorticity maximum is forecast to slide into the Pacific
Northwest on Thursday. Moisture and instability is lacking so
chances for thunderstorms are very low (<10%), but the HRRR
remains consistent in placing a few showers across the southeast
part of our forecast area over the higher terrain of Grant County.
12Z HREF and NBM probabilities for precipitation do not support
putting a "slight chance" mention for showers in the forecast so
have omitted due to low confidence.
Friday, heights rise across the forecast area with a warming trend
and mostly dry conditions across the forecast area. Plunkett/86
LONG TERM...Saturday through Wednesday...Good consensus amongst
ensemble guidance that sensible weather concerns through the
extended period will revolve around increasing afternoon
temperatures each day and potential convective activity during the
midweek.
Overall, ensemble members in good agreement in the region being
under the influence of an upper level ridge centered over the
Plains through at least Wednesday next week. The increasing high
pressure over the region will result in temperatures increasing
several degrees day to day, with moderate confidence (50%) of
Wednesday being the warmest day in the period. Though at the end
of the period, low percentages of the GFS(10%), the ECMWF(22%)
and Canadian(20%) ensemble members indicate a ~20% chance of
exceeding 100 degrees in the Tri-Cities area on Wednesday
afternoon. While a warm-up is expected, confidence is very low
(15%) on detailed temperatures.
The other feature to direct our attention to will be a weak upper
low developing off the CA coast, and moving inland over the Desert
Southwest Monday into Wednesday. Ensemble guidance is in fairly
high agreement in this feature developing, with all ensemble
cluster solutions showing this feature, with very minimal
differences in strength, timing, and position. As a result,
ensembles indicate increasing PWATS from the south and east as the
low pushes inland. This, in tandem with increasing surface based
instability, will result in at least isolated thunderstorms
developing in the afternoon Tuesday and Wednesday over the
mountainous terrain in northeast OR, though confidence in
intensity and coverage is low(30%).
Otherwise, under the influence of the upper ridge, there is
moderate confidence (40-60%) in dry conditions prevailing across
the forecast area with light diurnally driven winds each day.
Lawhorn/82
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 42 73 45 79 / 0 0 0 0
ALW 47 77 51 83 / 0 0 0 0
PSC 49 80 51 85 / 0 0 0 0
YKM 43 78 47 83 / 0 0 0 0
HRI 47 78 49 84 / 0 0 0 0
ELN 44 76 48 81 / 0 0 0 0
RDM 36 71 40 77 / 0 0 0 0
LGD 41 72 46 75 / 0 0 0 0
GCD 39 73 43 76 / 0 0 0 0
DLS 46 77 48 81 / 0 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...Wind Advisory until 11 PM PDT this evening for ORZ041.
WA...Wind Advisory until 11 PM PDT this evening for WAZ024-026.
&&
$$
SHORT TERM...86
LONG TERM....82
AVIATION...87
Area Forecast Discussion
National Weather Service Shreveport LA
1001 PM CDT Wed May 31 2023
...New UPDATE...
.UPDATE...
Issued at 915 PM CDT Wed May 31 2023
As of 945 PM CDT, temperatures have fallen into the mid-70s with
some lingering high clouds in an otherwise mostly clear sky.
Surface winds remain light and easterly with dew points expected
in the lower 60s. This makes for another fairly average night
conditions-wise temperature minimums in the upper 60s as a result.
Fog also remains possible overnight in Deep East Texas.
With weather and observed trends continuing as anticipated,
forecast grid adjustments were not necessary at this time. /16/
&&
.SHORT TERM...
(This evening through Thursday Night)
Issued at 255 PM CDT Wed May 31 2023
Nice field of cumulus clouds over most of our four state area.
Towering earlier in NE TX, but just some left over outflow
boundaries now and one lonely cell near Longview. Most of the
convection is now firing south of our area in the Jasper and
Derider vicinities. HRRR is not excited about anything different
happening through the remainder of the afternoon. The weaking and
elongating shear axis can be seen well on the water vapor imagery
right over Toledo Bend country for the most part. Otherwise, a
couple of sites have reached 92 along I-49. Most sites are nearing
90 at this time. Winds are all over the place, but seemingly NE-
SE less than 10 mph or lots of calm obs. So, "Play it again Sam"
seems to be on course for another 24 hrs, just slightly warmer
along a south of I-20 and in the nights to come. Highs again
tomorrow will be around 90 degrees, just slightly above late May
averages. Lows are gaining traction back towards that mark. /24/
&&
.LONG TERM...
(Friday through next Tuesday)
Issued at 255 PM CDT Wed May 31 2023
With the Ern Gulf upper low progged to drift ESE through the Ern
Gulf Friday, the residual weakness aloft extending NW from this low
across N LA/Srn AR is expected to erode as ridging aloft expands NE
across E TX/Wrn LA, with increased subsidence resulting in hot,
humid, and mostly dry conditions areawide. In fact, max temps will
reach or exceed 90 degrees across the region, with a few mid 90s not
out of the question especially across portions of N LA. However,
this will be short-lived as a spoke of energy developing along and
ahead of troughing aloft over the Rockies begins to shift E along
the Red River Valley of NW TX/Srn OK. Remnants from this shortwave
should begin to erode the ridging in place Friday night/Saturday
morning, and interact with strong diurnal heating during the day
Saturday to enhance scattered convection development across much of
the region during the afternoon. Have maintained likely pops NW of
I-30 Saturday afternoon, with mid and high chance pops elsewhere as
overall shear will remain quite weak, and the convection very
outflow dominant. Did maintain slight chance pops Saturday evening
over much of the area to account for any residual convection,
although this should quickly diminish with the loss of
heating/instability.
Another piece of energy aloft remains progged to traverse the region
during the day Sunday, and again will interact with diurnal heating
to enhance scattered convection once again, where mid and high
chance pops were maintained over much of the area. Isolated
convection may again lingering during the evening mainly over E
TX/Wrn and Cntrl LA, with the lingering weakness aloft expected to
gradually sink SSW into Cntrl/SE TX and Srn LA. The GFS is the
outlier in trying to mix much drier air SW into the Mid-South and
Lower MS Valley while eventually backdooring into the region Monday,
which seems too aggressive given the fact that the deeper troughing
aloft will remain well to the E from the OH/TN Vallies E to along
the Ern Seaboard. While the NBM does suggest that some drier air may
try and backdoor SW into the region Monday, the lingering weakness
aloft may still help focus isolated to widely scattered convection
during the afternoon especially over E TX/Wrn and Cntrl LA, before
diminishing by sunset. Hot and mostly dry conditions will persist
through the remainder of the long term, although the slightly drier
air backdooring in may take a bit of the edge off of heat indices,
especially as ridging aloft building over the Plains begins to
expand SSE into the region. /15/
&&
.AVIATION...
(00Z TAFS)
Issued at 701 PM CDT Wed May 31 2023
For the 01/00Z TAF update, VFR conditions are expected through
the period with the main exception being with FG possible in KLFK
by 01/10-14Z. Otherwise, light winds will remain from the east at
5-10 mph. /16/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 68 90 71 92 / 0 10 0 10
MLU 66 90 69 92 / 0 10 0 0
DEQ 62 89 66 90 / 0 10 0 10
TXK 65 90 69 93 / 0 10 10 10
ELD 63 88 67 90 / 10 10 0 10
TYR 68 89 69 90 / 0 10 0 10
GGG 68 89 68 91 / 0 10 0 10
LFK 67 90 68 91 / 0 10 0 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
SHORT TERM...16
LONG TERM....15
AVIATION...16
Area Forecast Discussion
National Weather Service Las Vegas NV
855 PM PDT Wed May 31 2023
.SYNOPSIS... An area of low pressure will move east and into Mohave
County this afternoon and will bring isolated to scattered rain
showers, and a slight chance of thunderstorms, particularly over the
higher elevations today. No impactful rainfall amounts are expected,
but these storms will be capable of producing lightning, small hail,
and wind gusts around 30 mph. Chances for showers persist over the
southern Sierra and central Nevada on Thursday and Friday with
similar thunderstorms risks expected each day. Dry and warmer
weather is forecast for the weekend.
&&
.UPDATE...Current satellite imagery shows the upper-level cut-off
low spinning over western Arizona. This system was responsible for
the isolated showers and thunderstorms across portions of the area
today. These showers and thunderstorms have largely dissipated with
the loss of daytime heating to fuel convection. Another round of
isolated showers and thunderstorms will be possible tomorrow
afternoon, but will be mainly limited to the Sierra and Southern
Great Basin. Temperatures will continue to remain a few degrees
below normal through the end of the work week, but will return to
normal in time for the weekend.
&&
.SHORT TERM...Today through Friday.
We had some showers/thunderstorms develop around daybreak in eastern
San Bernardino County but they continue to diminish. The center of
the upper low is currently in far southeastern California and will
be slowly working its way into western Arizona during the afternoon
hours. Moisture and instability are quite limited and with the low
moving away dynamics will be marginal as well. However, isolated to
scattered showers and thunderstorms are expected to develop,
particularly over the higher elevations and beneath the colder air
aloft (Mohave County). The latest couple of HRRR runs and the HREF
actually diminish the SBCAPE during the afternoon but 100-300 J/kg
will still be available. Lightning, small hail due to cold
temperatures aloft, and sudden gusty winds will be possible with any
storms today. Today`s high temperature should remain in the 80s in
Las Vegas which is well below normal. However, we had a high of only
68 degrees on this date in 1991.
The upper level system will continue to slowly move east Thursday
and Friday. As it pulls away, precipitation chances should diminish
each day. On Thursday, the focus will be across the Southern Great
Basin where continued troughing will sit and instability will
develop in the afternoon. The latest HREF is indicating at >50%
probability of these storms to produce wind gusts greater than 30
mph across Esmeralda, central Nye and northern Lincoln Counties.
By Friday, precipitation chance shift into central Nye through
Lincoln County and favoring northern Lincoln County. Temperatures
will slowly trend higher and should be close to the seasonal normals
by Friday.
.LONG TERM...Saturday through Wednesday.
Weak ridging will be in place over the weekend across the southern
Great Basin and Mojave Desert. The ensembles are in good agreement
that the next upper level low will form off of the southern
California coast on Sunday afternoon. However, mostly sunny skies
and dry conditions will be the rule for the weekend other than some
increase in southwest winds across the Mojave Desert on Sunday. The
upper low will move onshore during the day on Monday and both the
GEFS and EPS ensemble means have the upper low located over
southeast California in a nearly identical position to the current
upper low (just slightly weaker). The exact impacts from the upper
low are little murkier but the ensembles support some increase in
shower and thunderstorm activity at least over the higher terrain
each afternoon Monday through Wednesday. Temperatures will once
again trend lower starting on Monday under the influence of the
upper low and return to below normal levels on Tuesday and
Wednesday.
&&
.AVIATION...For Harry Reid...Scattered thunderstorms are expected to
develop near the terminal later this afternoon, mainly to the south
and southeast. As a result, there is the potential for outflow winds
with gusts as high as 30kts to affect the field, generally after
22Z. Until then, winds less than 10kts with easterly components can
be expected. Once thunderstorm activity ends early this evening
expect southerly winds that will become light and variable
overnight. Additional thunderstorms are possible tomorrow, although
coverage should be less, limiting the threat of outflow winds.
For the rest of southern Nevada, northwest Arizona and southeast
California...Overall, south to southwest winds are expected at area
terminals today into Thursday. Scattered areas of convection are
still expected to develop this afternoon across the area, and any of
these storms will be capable of producing gusty outflow winds, along
with lower ceilings and obscured terrain. Storms should dissipate
after sunset allowing winds to return to normal diurnal patterns.
Additional convective activity is again possible on Thursday,
although the coverage should be less.
&&
.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&
$$
UPDATE...Stessman
SHORT TERM...Czyzyk
LONG TERM...Czyzyk
AVIATION...Planz
For more forecast information...see us on our webpage:
https://weather.gov/lasvegas or follow us on Facebook and Twitter