Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/26/22
AREA FORECAST DISCUSSION
National Weather Service Albany NY
1032 PM EDT Thu Aug 25 2022
.SYNOPSIS...
A frontal boundary will slowly drift north as a warm
front overnight with scattered showers and isolated thunderstorms
mainly along and north of Interstate 90. Friday, low pressure moving
from the lower Great Lakes to New England will bring scattered
showers and thunderstorms. For the weekend, high pressure building
in from Ontario and Quebec will bring mainly fair weather.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
.UPDATE as of 1030 pm EDT...A cold front has become stationary
just south of the northern Catskills, Capital Region and central
Berkshires. A weak disturbance is moving along the boundary
producing some isolated showers over the northern and central
Berkshires and southern VT. Other showers and a few
thunderstorms continue upstream over west-central NY. These
showers and thunderstorms are with the better surge of warm
advection, as the warm front lifts northward. The trend will be
based on the latest 3-km HRRR and NAM for the scattered showers
and isolated thunderstorms increased along and north of the
Mohawk River Valley into the southern Adirondacks after midnight
with the best coverage in the early morning hours. Some weak
elevated instability is present so we kept isolated
thunderstorms in. The clouds will be variable across the region
with some some mid and high clouds from a wave near the mid
Atlantic Coast lifting northward and also clouds along and north
of the stationary front. Some patchy fog may form near the CT
River Valley in eastern Windham County, southern VT. Some quick
cooling of the temps occurred north and west of the Capital
Region with temps falling into the upper 50s to mid 60s, these
temps may drop off slightly and steady. We continue with lows in
the upper 50s to mid 60s across the region.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
Severe thunderstorms are possible Friday. The Storm Prediction
Center has place most of the Albany Forecast area in a Slight Risk
for severe thunderstorms on Friday.
A mid-level vorticity maximum is forecast to reach the St. Lawrence
Valley by late afternoon. An associated surface low will migrate
eastward into New England during the day with a trailing cold front.
A mix of sun and clouds during the morning is expected with
widely scattered showers and isolated thunderstorms expected
along the warm front. A relatively moist boundary layer will
destabilize through midday with surface dewpoints generally in
the 60s F. Moderate buoyancy coupled with some enhancement to
mid-level flow (30-40 kt at 500 mb) will contribute to the
potential for storm organization. Scattered thunderstorms are
forecast by the mid afternoon mainly in the form of
multicellular clusters and bands of storms. A few transient
supercells are possible and some risk for large hail and perhaps
a tornado could develop with the most intense storms. This
activity will likely diminish during the evening as the sun`s
heating wanes and the cold front passes east of our area. Highs
on friday from the 70s in the southern Adirondacks to near 90 in
the mid Hudson Valley.
Friday night winds will become northwest but temperatures won`t fall
too fast as the air mass behind the cold front isn`t initially
very cool or dry. Temperatures will be comfortable with lows in
the 50s and 60s.
Saturday and Saturday night look to be mainly fair and seasonable as
high pressure builds across New York and New England. Highs Saturday
from the 70s in the higher terrain to the mid 80s in the Mid Hudson
Valley. With light to calm winds and the possibility of good
radiational cooling, some valley fog may form late Saturday
night into early Sunday morning. Lows Saturday night low 50s to
low 60s with a few 40s in the normally colder locations.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
Summer warmth and humidity will occupy the first half of the long
term period before a potent cold front tracks through the Northeast
Tuesday into Wednesday resulting in a notable air mass change. In
fact, will feel more like fall just in time for the start of
September. Read on for details.
We start the long term off Sunday into Monday with weak sfc high
pressure in place and weak ridging aloft. Deterministic guidance
still suggests that weak shortwaves tracking along the northern
periphery of the ridge on Sunday could provide just enough forcing
to result in diurnally driven showers or isolated storms mainly in
the eastern Catskills. Otherwise, expecting mostly sunny skies and
warmer temperature well into the 80s for most of the region and
slightly higher humidity compared to Saturday as the ridge axis
slides to our east and southwest return flow is induced. Ridging
remains overhead heading into Monday but guidance deviates if
ridging will break down in response to shortwaves tracking eastward
from the Great Lakes (GFS/CMC solutions) or if it will remain
steadfast and maintain mainly dry conditions (ECMWF solution). Given
ongoing uncertainty, we continue to show slight chance POPs on
Monday to account for the potential for a few isolated afternoon
showers or storms. Otherwise, southwest flow will keep summer warmth
and humidity in place with highs topping out near 90 in the Hudson
Valley including the Greater Capital Region and mid-Hudson Valley
with mid to upper 80s elsewhere (low 80s high terrain). Warm
temperatures coupled with high humidity (dew points mid to upper
60s) could result in elevated heat index values in the low to
possibly mid-90s on Monday. Not enough widespread heat index values
at or above 95 to mention heat advisory potential in the hazardous
weather outlook but will continue to monitor.
Deterministic guidance still not on the same page regarding the
overall amplification and timing of the upper level trough expected
Tuesday into Wednesday due to discrepancies regarding if the
northern stream trough and a compact shortwave in the northern
Plains phase or not. The ECWMF shows phasing occurring which results
in a more amplified trough digging into the Ohio Valley while the
GFS and CMC do not and therefore keep the northern trough weaker and
escaping into Ontario. We maintained chance and even likely POPs for
Tuesday as the sfc cold front should still track through the
Northeast but should the ECWMF solution verify, a stronger front can
be expected.
The secondary and true cold front pushes through on Wednesday as the
trough axis tracks through the region so we maintained slight chance
POPs before a northwesterly wind shift will usher in a much cooler
and drier air mass for Thursday. It will feel more like fall just in
time for Sept 1 with PWATs below 0.5", 850hPa isotherms falling
below 10C and breezy conditions. High temperatures could struggle to
climb out of the 70s.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Despite a few isolated showers developing late this afternoon
in response to a weak front sliding south and eastward through
the terminals, VFR conditions persist. Any isolated showers will
dissipate after sunset with mid and high level clouds from the
mid-Atlantic spreading northward tonight. SCT-BKN clouds near 10
to 15kft should prevent much fog from developing although GFL
may be far enough north that MVFR ceilings could develop before
sunrise. Due to low confidence, only include clouds at SCT025
from 09 UTC to 12 UTC.
Then, two periods of showers and storms are possible during the
day on Friday. First, scattered showers and isolated storms are
possible from 14 - 17 UTC at all TAF sites before a brief break
for some dry weather ensues during the early afternoon hours.
Then, a cold front tracking south and eastward through the
region will likely lead to a second period of more numerous showers
and storms from 20 UTC to 00 UTC. Storm coverage is still a bit
uncertain but it is possible that a terminal could be impacted
by storms more than once. Any storm could result in MVFR or even
IFR ceilings and visibility.
Light and variable winds tonight shift to the south and southwest
by 14 - 16 UTC and will increase to 7 to 12 kts with gusts to
15kts through sunset. Brief stronger wind gusts are possible in
any strong to severe storm.
Outlook...
Friday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Saturday: No Operational Impact. NO SIG WX.
Saturday Night: No Operational Impact. Patchy FG.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: Low Operational Impact. Slight Chance of SHRA...TSRA.
Monday Night: Low Operational Impact. Slight Chance of SHRA...TSRA.
Tuesday: Moderate Operational Impact. Scattered SHRA...TSRA.
&&
.HYDROLOGY...
Some storms Friday may produce locally heavy rainfall leading
to ponding of water in urban, low lying and poor drainage areas.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...SND/Wasula
NEAR TERM...Wasula
SHORT TERM...SND
LONG TERM...Speciale
AVIATION...Speciale
HYDROLOGY...SND
Area Forecast Discussion
National Weather Service Denver/Boulder CO
836 PM MDT Thu Aug 25 2022
.UPDATE...
Issued at 836 PM MDT Thu Aug 25 2022
Tonight`s forecast is on track. We did not adjust any temperatures
as they are already cool but with cloud cover expected much of the
night across the area, they won`t drop that much more. Looking at
GOES-16 and area radars (KPUX and KCYS with KFTG down for the next
week for maintenance), there are batches lingering light rain
showers moving east mainly south of US-34. Not much rain is
reaching the ground with the showers though the foothills of
Jefferson and NE Park Counties may get another tenth of an inch of
rain or so. In general the trend is downward in intensity and
coverage. Thus, have reduced PoPs through 1 AM, and eliminated
them from many areas including the northeast corner of Colorado
and the far eastern zones of Washington/Lincoln Counties. After
2AM most if not all shower activity should diminish.
&&
.SHORT TERM...(This evening through Friday)
Issued at 202 PM MDT Thu Aug 25 2022
Showers and thunderstorms continue to develop over the high country
this afternoon. A few storms have formed over the burn areas, with
one warranting a flash flood warning over Cameron Peak burn area as
a result of local heavy rainfall rates. Expect this activity to
continue through the early evening hours with a chance for scattered
showers and a storm or two to spread eastward onto the adjacent
plains.
Friday will feature another day of higher coverage showers and
thunderstorms, mainly over the high country. The main trough axis
pushes through the region tomorrow providing a period of weak
ascent, marginal instability, and above normal moisture. This will
be enough to support scattered showers and thunderstorms with higher
coverage activity over the high country. Modest MLCAPE values (200-
600 J/kg) and bulk shear 25-35 kts will help sustain storms as well.
There is a chance for showers/storms to spread into the urban
corridor and plains as well. Hi-res guidance hints at the formation
of a boundary over the Palmer Divide in the afternoon which may aid
in development of showers or thunderstorms in that area. There is
some question as to how long the monsoonal sticks around as there
are hints of drying into the afternoon period as the trough advances
through the region. This may factor into overall precip. chances.
CAMs also display some spread in the timing of the precipitation
with the HRRR initiating activity mid morning as opposed to other
solutions in the early afternoon over the high country. Overall,
there will be moderate to high chances over the high country in the
afternoon with lower chances over the plains (< 35%). Gusty winds
may be a threat with storm activity over the plains as soundings
over the plains take on an inverted-v profile.
.LONG TERM...(Friday night through Thursday)
Issued at 202 PM MDT Thu Aug 25 2022
|For late Friday night and Saturday there will be drier air
filtering into Northern Colorado behind the exiting upper trof
into the central plains. High pressure ridging will build during
the day on Saturday. Temperatures will also be warmer, with
readings nudging back into the 90s across lower elevations. There
will still be a slight chance for showers and thunderstorms but
looks like these will be confined to the higher mountains and
especially locations south of the Interstate 70 corridor through
Summit and Park counties.
The chances for showers and thunderstorms will increase on Sunday
across the mountains and plains with an approaching upper trof
approaches Colorado. However, moisture appears a bit limited so
overall coverage of storms more likely in the scattered category
and more numerous in the northern mountains. Temperatures will
likely be similar or just a shade cooler with more clouds.
There is more uncertainty and lower confidence in next week`s
forecast due to the model`s handling of the early week trof. 00Z
European run weakens the low and drops in southward over Colorado
through the early part of the week while the GFS develops a closed
low across Kansas and over the southern high plains through the
middle of next week. However, new 12z European solution keeps a
progressive trof with the main trof over the Great Lakes by
Tuesday. So certainly not much run to run consistency as of late. Overall
looks like temperatures would be seasonal early in the week then
a return to hot and dry from the middle of the week onward with
building ridge of high pressure anchored over the Great Basin and
Northern Rockies. Won`t make many changes to extended forecast in
regards to showers chances and temperatures, especially if long
range models do more flips.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 555 PM MDT Thu Aug 25 2022
VFR conditions through Friday evening. Radar is showing areas of
light rain showers moving WNW to ESE across the terminals.
Instability is weak enough that we do not expect any lightning
with any of the shower activity. After about 02Z the showers
should either be dissipated or have moved east of the terminals.
Winds behind the showers have weakened below 20 kts out of the WNW
at BJC and DEN, and that trend will continue through 02Z and
beyond as drainage winds around 10 kts kick in at DEN and APA (SSW).
BJC should be about west all night and under 10 kts.
Tomorrow looks like a little less shower activity will be
expected. Winds should me mostly out of the east midday 10-15 kts,
but they will probably shift to the NW in the afternoon hours
at 10-25 kts or so (gusts), due to convective activity to the
west of the terminals. No thunder is anticipated.
&&
.HYDROLOGY...
Issued at 202 PM MDT Thu Aug 25 2022
There will be an elevated threat for flash flooding over the
Cameron Peak and East Troublesome burn areas tomorrow and a
limited threat for the other burns. Monsoonal moisture and
marginal instability will promote higher coverage showers/storms
tomorrow afternoon. Storm motions will be modest as well. A few
stronger storms will be capable of producing localized heavy
rainfall which may cause impacts over the burn areas.
There will be limited threats of flash flooding on the burn scars,
mainly Friday evening and again on Sunday. Saturday looks to be
the driest day with only isolated coverage of storms. The long
range forecast is shaping up drier and warmer for the middle of
next week with mainly isolated coverage of storms.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Schlatter
SHORT TERM...Mensch
LONG TERM...Entrekin
AVIATION...Schlatter
HYDROLOGY...Mensch
Area Forecast Discussion
National Weather Service Boston/Norton MA
1000 PM EDT Thu Aug 25 2022
.SYNOPSIS...
Dry and quiet weather tonight for much of southern New England.
Patchy fog across portions of the Cape and Islands. Increasing
humidity with scattered showers and thunderstorms developing
Friday afternoon and evening ahead of a cold front. Slightly
warmer than normal temperatures this weekend away from the
coast, then more heat and humidity likely returns next week.
While dry weather is expected for much of this weekend into
Monday, a brief afternoon evening shower or thunderstorm may
develop each day. The risk of showers and thunderstorms will
increase late Tuesday into Wednesday as a strong cold front
approaches.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
10 PM Update
Forecast remains on track and no adjustments are to the near-
term forecast are needed at this time.
Previous Discussion
Highlights
* Increasing mid/high clouds tonight. Patchy fog and low clouds
across the Cape/Islands and perhaps portions of the CT River
Valley.
The main weather problem this evening remains the extent and
timing of fog across portions of the Cape and islands. The
encroaching mid and high level clouds will soon obscure our
real-time monitoring via satellite. The observation at Nantucket
was right along the western edge of this fog back, which was
also just offshore of Chatham. Expecting a light SE flow to
continue for a little bit longer before turning a bit more from
the S. Thus, fog should eventually overspread at least Nantucket
and the outer Cape for a time overnight.
Regional radar data showed showers continuing to diminish after
sunset. Minor tweaks to temperatures overnight, too.
Previous Discussion...
Mid level ridge axis flattens out over New England this evening,
while we remain under cyclonic flow. High pressure will build
further offshore tonight.
Dry and quiet weather anticipated across southern New England
tonight. Do have a subtle shortwave lifting across the eastern
Great Lakes, which should be enough to bring us some increasing
mid/high clouds. May be difficult for temps to drop given the
mid/high clouds in place despite the light winds. Low temps
bottom out in the 60s.
Will see flow become south/southwesterly in the lower levels,
bringing increasing low level moisture. This will be enough to
spread low clouds into the Cape along with Nantucket and perhaps
Marthas Vineyard. Do have some uncertainty in how low
visibilities get as winds may stay up high enough to keep the
fog at bay. However, given the increasing low level moisture
leaned toward the GLAMP and NBM guidance. This puts the
visibilities into the 1/2 roughly 4 SM range. Should see most of
this burn off fairly rapidly as the sun rises.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Highlights
* Cold front slides in bringing showers and thunderstorms.
Should see this activity tapering off Friday evening as the
cold front slides through. Strong to severe storms possible
with the main risk of damaging wind gusts, locally heavy
downpours, hail and an isolated tornado cannot be completely
ruled out.
Cyclonic flow still in place across southern New England Friday
into early Saturday. Will have a broad deamplifying trough lift
from the eastern Great Lakes early on Friday into northern New
England by Friday evening. An approaching cold front will bring
the risk of showers/storms ahead of it.
Not a whole lot of change from the previous forecast. The
environmental parameters essentially look the same with MLCAPE
values of up to 1000 J/kg, deep layer shear in the 0-6 km layer
of roughly 25-35 kts and surface dew points in the low/mid 60s.
Will note that I have thrown out the NAM guidance as it has once
again advected too high a dew point airmass over the region,
which brings MLCAPE values into the 1500-2500 J/kg range. Leaned
toward the vast majority of guidance, which again keeps us in a
few hundred to perhaps 1000 J/kg of MLCAPE. Some other
parameters to keep in mind is there are a few hundred J/kg of
hail growth zone CAPE, 6-8 degree Celsius low level lapse rates,
poor mid level lapse rates, a few hundred to perhaps 1000 J/kg
of DCAPE and PWATs approaching 1.5-1.75 inches. Lastly, given
the increasing southwesterly flow in the low/mid levels will
have 0-1 km SRH approaching 100 m2/s2 across the CT Valley into
portion of central MA along with low LCL heights. Given this
environment there will be the risk of strong/severe storms. The
main threat will be damaging straight line wind gusts, locally
heavy downpours, some instances of large hail and an isolated
tornado cannot be ruled out. Have leaned on the HRRR NCAR Neural
Network Convective Hazard forecast, which still indicates wind
as the primary risk. Given CAMs showing more of a multicellular
cluster think this will be the main threat along with heavy
rain, but given the environment a supercell or two not out of
the question which would enhance the hail risk and an isolated
tornado. Timeframe wise still thinking that roughly 12 PM until
8-10 PM will be the window for the risk. Mitigating factors to
the severe risk are the poor mid level lapse rates and do have
some question on the strength of the forcing with some height
rises aloft during the day given the deamplifying trough.
Regardless, think that the latest SPC Day 2 Outlooks highlights
the greatest risk area well.
High temps topping out in the 80s across southern New England
on Friday. Should see temps drop a bit during the evening in
wake of the frontal passage, but for most will be in the 60s.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Highlights...
* Slightly warmer than normal this weekend away from the coast,
with heat/humidity returning early next week
* A brief isolated shower or thunderstorm possible this weekend
into Monday, but dry most of this time
* Increasing risk of showers/thunderstorms late Tuesday into
Wednesday
Have average confidence in the overall forecast through early
next week, then significant model differences arise Tuesday
into Thursday. This looks to be mainly a timing issue, so stuck
rather closely to the ensemble mean of the NBM for that portion
of this forecast.
Expecting nearly zonal mid level flow to be replaced by mid
level trough over the eastern USA by the middle of next week.
The 25/12Z ECMWF has a more phased approach and shifts this
trough eastward quite earlier than the other guidance. The GFS
and CMC solutions lag this timing and have a cutoff mid level
low farther to the SW. Between Tuesday and Thursday, the
solutions flip, with the ECMWF solution being the farthest
west.
At the surface, high pressure this weekend slowly moves offshore
early next week. A series of cold fronts then should approach
southern New England Tuesday into Wednesday. Expecting dry
weather most of this portion of the forecast, although it be
getting increasingly humid next week. We will likely have to
wait until a pair of cold fronts arrive towards the middle of
next week to get a shot at additional rainfall.
Expecting temperatures to be lower this weekend than most of
next week. Once high pressure moves offshore, the SW return flow
will lead to the increase in heat and humidity.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
Tonight...High confidence away from the Cape/ACK.
VFR across the interior with light and variable winds.
Anticipate low stratus and perhaps some patchy fog to spread
into the Cape/Islands. More confident at this point in the low
clouds spreading in, but winds may stay high enough to keep from
IFR/LIFR visibilities at some locations.
Friday...High confidence in trends, moderate in exact timing.
Should see any lingering low clouds/fog across the Cape/Island
lift by 12-15Z. Elsewhere VFR with increasing S/SW winds.
Showers and thunderstorms spreading in from west to east.
Confidence at this point highest in the thunder potential across
the interior from ORH/BAF/BDL. Should see most of the activity
after 18Z. Could see gusty winds, heavy rain and perhaps some
small hail if a stronger storm passes over a terminal across the
interior. Less confident toward E MA/SE MA coast in activity
holding together.
Friday night...High confidence in trends, moderate in timing.
Any lingering showers/storms tapering off generally before 06Z.
Expecting VFR conditions with SW winds at 5-10 kts to start.
Shifting to the WNW/NW after 06Z around 5 kts.
KBOS...High confidence in TAF.
KBDL...High confidence in TAF.
Outlook /Saturday through Tuesday/...
Saturday: VFR. Slight chance SHRA.
Saturday Night through Monday: VFR.
Monday Night: VFR. Slight chance SHRA.
Tuesday: VFR. Breezy. Chance SHRA, isolated TSRA.
&&
.MARINE...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
Tonight...Moderate confidence.
Increasing southerly flow late tonight. Seas of 2-4 ft. Am
anticipating low clouds/stratus to spread across mostly the
eastern waters and near the Cape/MVY/ACK. Anticipate the fog
could be locally dense at times in spots, but generally will be
in the 1-3 NM range.
Friday and Friday night...High confidence.
Increasing S/SW flow on Friday ahead of the incoming cold
front. Should see wind speeds of 10-15 kts by the afternoon with
gusts of 15-20 kts. Any stratus/fog lifts during the morning.
Could see thunderstorms approaching the waters during the
afternoon. Some question if they hold together during the
evening as the cold front is passing. Winds shift once the front
passes through Friday night. Should see winds of 5-10 kts
Friday night becoming W/WNW/NW late. Seas 2-4 ft.
Outlook /Saturday through Tuesday/...
Saturday through Monday Night: Winds less than 25 kt.
Tuesday: Winds less than 25 kt. Seas locally approaching 5 ft.
Slight chance of rain showers.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...None.
&&
$$
SYNOPSIS...Belk/BL
NEAR TERM...Belk/RM
SHORT TERM...BL
LONG TERM...Belk
AVIATION...Belk/BL
MARINE...Belk/BL
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
637 PM CDT Thu Aug 25 2022
...New AVIATION...
.SHORT TERM...
(This evening through Friday Night)
Issued at 226 PM CDT Thu Aug 25 2022
Trough over the Ohio River Valley begins to push further south
through the Short Term period. This will also push the cold front
over CRP CWA further south into the Northern Ranchlands by this
evening. Record PWAT values near 2.5 inches and CAPE values around
1500 J/kg are expected for the Ranchlands this afternoon. HRRR has
isolated showers and thunderstorms being initiated in our northern
counties from the convection currently over CRP`s southern counties
and Gulf Waters. This activity, combined with the afternoon
seabreeze, has caused isolated showers and thunderstorms to already
form east of I-69E in Kenedy county. However, as diurnal heating
dissipates tonight, most of the showers and thunderstorms will as
well. Main impacts will be frequent lightning, heavy downpours, and
gusty winds. Nuisance flooding is possible today. Have high
temperatures in the upper 90s to lower 100s out west today with lows
in the upper 70s as a few clouds linger through the night with a
isolated rain chances still possible.
Friday is forecast to be our best chance for rain over the next few
days. Models have good agreement regarding a 30 to 60 percent POPs
throughout the day. But, they are not in good agreement with where
exactly these showers and thunderstorms will form. Right now, HRRR
has a line of storms forming tomorrow afternoon in the Ranchlands
and slowly dissipating as it moves south towards the Valley. The RGV
does have a chance to see rain tomorrow as well, but the Northern
Ranchlands will have the better probability. Since PWAT values are
still expected to be near 2 inches, these showers could be heavy
rain producers with localized nuisance flooding in low-lying
areas with 1 to 2 inches per hour rainfall rates. High temperatures
tomorrow will be not as hot due to increased cloud cover. Highs
are forecast in the mid to upper 90s across Deep South Texas.
&&
.LONG TERM...
(Saturday through next Wednesday)
Issued at 226 PM CDT Thu Aug 25 2022
Generally conditions look to be somewhat drier this weekend with
a possible uptick in rain chances next week. Continued model
differences in placement of mid-level features add uncertainty
and low confidence to the forecast.
Residual moisture from the expected Friday convection could linger
into early Saturday before a mid-level ridge builds back into the
region lowering the mean RH in the 500-300mb layer. Below 600mb
sufficient moisture resides to get an isolated sea breeze shower
or two going. Same goes for Sunday however GFS shows the mid-level
dry air getting a little deeper, while the ECMWF`s wetter bias is
rearing its ugly head and seems to be an outlier indicating much
higher rain chances. Consensus shows 10-25 percent for the weekend
and this what the previous and current forecast will trend with.
Early to midweek, uncertainty remains in the air and will be a big
factor as the ECMWF maintains a presence of the mid-level ridge over
the CWA while the GFS backs off showing a weakening ridge. Both
models suggesting a cold front moving into north central Texas
Tuesday likely to become stationary with a general increase or
pooling of moisture south of the front although the GFS seems to
indicate a slower increase in moisture Monday and Tuesday with a
better surge midweek. Model guidance along with the general
consensus trends with slight chance of isolated sea breeze activity
Mon-Tue with scattered convection Wednesday and Thursday. The
afternoon forecast package does not deviate from this trend. Can
not rule out any slow moving thunderstorm to produce localized
heavy downburst.
No big changes in the temperature outlook with this part of the
forecast rather persistent and in good agreement among the latest
model suite. Seasonal highs and lows can be expected with highs
ranging from near 90 degrees at the coast, mid to upper 90s inland
to the lower 100s far west. Lows range 75 to 80 degrees overnight
lows. Heat indices range from 103 to 108 each afternoon. Expect
temperatures to cool down after a douse of rain.
&&
.AVIATION...
(00Z TAFS)
Issued at 629 PM CDT Thu Aug 25 2022
Satellite is showing BKN to OVC high clouds across all three TAF
sites this evening in the wake of some storms that occurred
earlier today. VFR conditions are expected to prevail through most
of the period, except for in any heavier showers and
thunderstorms that develop tomorrow, where MVFR conditions will be
possible. Chances for showers and thunderstorms to impact the
airfields are low for tonight and then increase through the day
tomorrow, with most activity expected in the afternoon. Outside
any storms, southeast winds will become light tonight through
Friday morning, then increase to become gusty by the afternoon.
&&
.MARINE...
Issued at 226 PM CDT Thu Aug 25 2022
Tonight through Friday Night: Isolated to scattered showers and
thunderstorms are possible through the Short Term period with
frequent lightning, heavy downpours, and gusty winds being the
main threat. Friday is forecast to be the best day for these to
occur. Otherwise, seas remain low at 1 to 2 feet with mostly light
southeast winds expected.
Saturday through Tuesday:The persistent weak to moderate pressure
gradient across the western Gulf of Mexico remains in place
through the weekend and early next week. Seasonal light to
moderate onshore flow and slight seas can be expected. Occasional
increase in convection Sunday and and next week may allow for
periods of fresh southerly flow and higher seas but not
anticipating any long duration small craft advisory conditions.
Any shower and especially thunderstorms will exhibit higher wind
and produce rough seas along with lightning and torrential
rainfall.
&&
.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE 79 94 78 94 / 30 50 10 20
HARLINGEN 77 94 76 95 / 30 50 10 10
MCALLEN 78 97 78 99 / 40 50 20 20
RIO GRANDE CITY 78 96 78 99 / 40 40 20 20
SOUTH PADRE ISLAND 79 88 80 88 / 30 50 10 10
BAYVIEW/PORT ISABEL 78 88 78 92 / 30 50 10 10
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...65-Soria
LONG TERM....59-GB
AVIATION...69-Farris
Area Forecast Discussion
National Weather Service State College PA
1055 PM EDT Thu Aug 25 2022
.SYNOPSIS...
After a generally rain-free night, the passage of a weak cold
front later Friday will touch off a few showers or
thunderstorms, mainly Friday afternoon and evening.
The weekend looks dry and seasonably warm, under the influence
of high pressure over the western Atlantic.
&&
.NEAR TERM /UNTIL 7 AM FRIDAY MORNING/...
A potent looking shortwave lifting over the Mid Atlantic is
supporting scattered convection this evening at the nose of
associated low level jet over south central Pa. Have boosted
overnight POPs above NBM to account for the passage of this
feature. Latest SPC mesoanalysis and RAP forecast indicate
overnight capes of 500-1000 J/kg over the southeastern part of
the forecast area, where thunder will remain possible. Further
north, only showers mentioned with POPs in the slight chance
category. The weakening low level jet and associated chance of
showers should pass east of the forecast area by dawn.
Latest SREF and NAMNest support patchy valley fog late tonight,
the result of a calm wind, gradually rising dewpoints and wet
ground in spots. Tonight will be somewhat milder than recent
nights, with lows by daybreak ranging from around 60F across the
northwest mountains, to around 70F in the Lower Susq Valley.
&&
.SHORT TERM /7 AM FRIDAY MORNING THROUGH SUNDAY NIGHT/...
On Friday, we`re still anticipating the development of
scattered afternoon/evening showers and thunderstorms associated
with the passage of a cold front. The parent shortwave and best
large scale forcing is progged to pass north of the state and
pwats not especially high, so expect coverage to be hit and
miss, with the highest POPs across the northwest mountains,
closest to track of mid level shortwave. In general, progged
deep layer shear is weak and the severe weather threat low.
However, slightly stronger mid level flow along the NY border
indicates a marginal risk of strong-damaging wind gusts up there.
Friday will be seasonably warm and sticky, with afternoon highs
ranging near 80 over the Alleghenies, to about 90 in the Middle
and Lower Susquehanna Valleys.
The weekend will be characterized by rising heights aloft, with
a decaying surface front somewhere near the Mason- Dixon line.
Although an isolated shower or thunderstorm can`t be ruled out
either afternoon over the south- central mountains and the Lower
Susquehanna Valley, we expect rain-free weather for the
majority. Weakening convergence with the above mentioned frontal
zone and a lack upper-level forcing should seriously limit
convective potential.
Saturday`s highs will range from the mid 70s over the northern
mountains, to the upper 80s in the Lower Susquehanna Valley.
Sunday will trend warmer, with highs ranging from the lower-
middle 80s in the Alleghenies, to the lower 90s in the Lower
Susquehanna Valley.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
Medium range guidance is in fairly good agreement in developing
a building upper ridge over the east coast into early next week,
downstream of an upper trough moving into the upper Midwest.
Ensemble mean 850mb temps rise to around 17-18C by Monday,
supportive of highs in the mid 80s to low 90s.
Shower/storm chances look to increase by Monday as lead
shortwave energy from the parent trough approaches western PA,
with some terrain-induced convection also possible in an
increasingly unstable airmass. Best chances for showers/storms
are currently in the later Tuesday timeframe along/ahead of an
approaching cool front. Will have to watch the potential for a
cutoff low breaking off the mean northern stream trough and
lingering to our west, which could heighten additional
precipitation chances later next week. However, given the
passing of the front and stout upper low in the vicinity of
Hudson Bay providing cool/drier northwest flow, expecting at
least a period of drier/cooler weather for mid-late week.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
Widely scattered showers will move across the area overnight
with only very brief reductions to MVFR possible. Elsewhere,
expect VFR conditions to prevail. With some rain at AOO,
wouldn`t be surprised to see some fog develop toward daybreak
Friday.
An approaching front may be the focus for some afternoon showers
and storms on Friday afternoon. Best chance looks to be across
the central and northwest airfields with somewhat lower chances
in the southeast. Prevailing VFR conditions with only brief
reductions to MVFR possible.
Outlook...
Sat-Mon AM...No sig wx expected.
Mon PM-Tues...Increasing chance of showers and storms with a
cold front approaching.
&&
.CLIMATE...
It`s been a hot and dry month so far in Harrisburg...
The average monthly temperature [through 8/24] is 78.5F or
+2.8F above normal and would rank as the 2nd warmest August on
record.
The total monthly rainfall [through 8/24] is 0.82" or -2.07"
below normal and would rank as the 4th driest August on record
at Harrisburg.
Hot temperatures and very little rainfall are forecast through
the end of the month.
Warmest August on record at Harrisburg:
1. 79.1F 2016
2. 78.5F 2022 (7 days left in the month)
3. 78.3F 2021
T4. 78.2F 1900, 1966, 2020
7. 77.7F 2002
Driest August on record at Harrisburg:
1. 0.53" 1995
2. 0.73" 1923
3. 0.81" 1909
4. 0.82" 2022 (7 days left in the month)
5. 0.93" 1977, 1957
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Jurewicz
NEAR TERM...Fitzgerald
SHORT TERM...Jurewicz/Fitzgerald
LONG TERM...Guseman/Banghoff
AVIATION...Banghoff
CLIMATE...
Area Forecast Discussion...UPDATED
National Weather Service Hanford CA
225 PM PDT Thu Aug 25 2022
.UPDATE...Updated Air Quality Issues Section...
&&
.SYNOPSIS...Above normal temperatures will continue across the
area through Friday. A cooling trend is expected to take place this
weekend. By Sunday afternoon, high temperatures will be below
normal for this time of year. A warming trend is expected to take
place early next week with temperatures rising above
climatological normals by Tuesday. Other than a few showers and
thunderstorms over the higher Sierra this afternoon, dry weather
will prevail across the area through the middle of next week.
&&
.DISCUSSION...Upper high pressure over the Eastern Pacific is
maintaining a very warm airmass over our area with a continuation
of above normal temperatures and another afternoon with triple
digit highs across the San Joaquin Valley, lower Sierra Foothills,
Kern River Valley and the Kern County Deserts. A weak shortwave
pushing into Norcal today has weakened the upper high enough for
temperatures to cool a few degrees from Wednesday when much of
our area approached dangerous heat levels.
Visible imagery is showing some build-ups near the Sierra crest
in Tulare County. HRRR is indicating enough instability and CAPE
for isolated showers and thunderstorms near the Sierra crest in
Tulare and Fresno Counties this afternoon. Increased onshore flow
on Friday will push out any mid/upper moisture east of our area on
Friday which will inhibit mountain convection. A slight cooling
trend is expected on Friday although temperatures will remain
above normal for late August.
SREF is showing a strong upper trough pushing into the PAC NW
this weekend. A piece of shortwave energy from the trough is
progged to drop southward off the CA coast on Saturday and Sunday
and bring significantly cooler temperatures to our area with
temperatures cooling down to sightly below seasonal averages by
Sunday. Latest NBM probabilistic guidance is indicating most of
the San Joaquin Valley has between a 50 and 70 percent chance of
maximum temperatures below 100 DEG F on Saturday and a 90 percent
or greater chance of maximum temperatures below 100 DEG F on
Sunday. RH progs are showing very little in the way of moisture
impacting our area this weekend so dry weather will likely
prevail with skies remaining mainly clear. A period of increased
winds is possible across the mountains and deserts of Eastern Kern
County on Saturday afternoon and evening as p-grads strengthen.
The medium range models are in excellent agreement in showing an
upper ridge building in the Rocky Mountain region early next week
and strengthening during the middle portion of next week with
excellent ensemble agreement. This will provide for a warming
trend to take place across our area next week with NBM guidance
indicating daytime temperatures rising back to above normal levels
by Tuesday and a return of widespread triple digit heat across
the San Joaquin Valley on Wednesday and Thursday.
&&
.AVIATION...Isolated showers and thunderstorms are possible near
the Sierra crest in Fresno and Tulare Counties through 01Z Fri
with local mountain obscurations possible. Otherwise, VFR
conditions will prevail across the Central CA interior through at
least the next 24 hours.
&&
.AIR QUALITY ISSUES...On Friday August 26 2022... Unhealthy for
Sensitive Groups in Fresno... Kern and Tulare Counties... and
Sequoia National Park and Forest.
&&
.CERTAINTY...
The level of certainty for days 1 and 2 is medium.
The level of certainty for days 3 through 7 is medium.
Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.html for additional information
an/or to provide feedback.
&&
.HNX WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
public/aviation/fire wx...DAS
pio/idss...MV
weather.gov/hanford
Area Forecast Discussion
National Weather Service Lincoln IL
904 PM CDT Thu Aug 25 2022
.SYNOPSIS...
Issued at 301 PM CDT Thu Aug 25 2022
A cold front across central Illinois will bring scattered showers
and thunderstorms, mainly this afternoon and evening. Dry
conditions will return Friday. Slightly cooler air Friday will
result in high temperatures in the lower to mid 80s.
&&
.UPDATE...
Issued at 903 PM CDT Thu Aug 25 2022
Boundary is still slowly moving south through central IL this
evening with two main areas of scattered showers and storms. One
in Champaign county that appears to be dissipating. The other area
is in Sangamon county. Storms continue to develop northwest of
Springfield and move east to southeast over the area. This may
continue for a couple of more ours seeing the electrical
activity is still present and the cloud tops are cold. HRRR model
is now showing the showers and storms continuing beyond 10 pm so
will be making adjustments to the pop/wx grids to reflect that.
Update will be out shortly.
&&
.SHORT TERM...(This evening through Friday)
ISSUED AT 301 PM CDT Thu Aug 25 2022
A cold front resides just north of I-72 this afternoon, with
widely scattered thunderstorms expected to develop near the front.
This should be most extensive early in the evening before slowly
dissipating and migrating southward overnight. By Friday
afternoon, the front should slip south of the central IL forecast
area with dry conditions across the area. Low cloud cover behind
the front looks to increase in northerly flow overnight, which
should help keep temperatures mild and limit fog potential. Lows
are forecast in the mid 60s tonight. A bit cooler temperatures are
forecast for Friday as the slightly cooler air mass and morning
cloud cover hold highs down to the lower to mid 80s most places.
.LONG TERM...(Friday night through Thursday)
ISSUED AT 301 PM CDT Thu Aug 25 2022
Fair weather is expected through Saturday with high pressure
behind the cold front dominating the weather. A high in the mid to
upper 80s can be expected, with seasonable humidity.
Thursday`s front will lift back north across the area Sunday,
bringing slightly warmer temperatures and higher humidity, along
with a chances for showers and thunderstorms Sunday into early
next week as a series of shortwaves move through. While timing and
evolution of the pattern midweek is highly variable among models,
it appears a cold front will push southward through the area
midweek, ending chances for precipitation and starting a cooling
trend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 633 PM CDT Thu Aug 25 2022
VFR conditions are expected at PIA and BMI through the evening but
MVFR vis and cigs are expected tomorrow morning through the
morning hours as lower clouds arrive from the northeast. Vis will
drop to around 5sm while cigs drop to 2kft. VFR conditions are
expected in the afternoon. SPI, DEC, CMI will all have VCTS for
2-3hrs this evening as a slow moving front drops through the area.
Then VFR conditions are expected through most of the night. CMI
should see some 5sm due to fog, but SPI and DEC wont. MVFR cigs
will also affect CMI during the early morning hours but then
become VFR during the afternoon. Winds will be northwest to north
at PIA and DEC, but southwest winds at SPI, DEC, CMI for a few
more hours before the front moves through, then northwest to north
winds expected the rest of the period. Wind speeds will less than
10kts through the period.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Auten
SYNOPSIS...37
SHORT TERM...37
LONG TERM...37
AVIATION...Auten
AREA FORECAST DISCUSSION...UPDATED
National Weather Service Jackson KY
1108 PM EDT Thu Aug 25 2022
.UPDATE...
Issued at 1108 PM EDT THU AUG 25 2022
As of 11 PM, a moisture gradient/gradient in PW remains near the
TN and KY border and across the Lake Cumberland Region to the
Cumberland Plateau area and portions of middle to eastern TN with
some moisture transport into the TN border counties. Convection
is occurring near or just south of the stateline from McCreary
County west to Wayne and Clinton Counties with some lightning
recently detected in portions of Fentress and Pickett Counties
TN. Model guidance such as recent RAP shows continued border have
additional moisture transport into the southwest portion of the
area into the overnight. Based on radar trends and trends in
convective allowing models, pops have been introduced into the TN
border counties earlier compared to previous forecasts as isolated
convection should spread east northeast overnight. A lull in
chances for convection may occur for a time around or for a few
hours after sunrise, before moisture increases from the west by
late Friday morning into Friday afternoon.
UPDATE Issued at 900 PM EDT THU AUG 25 2022
Cumulus has generally dissipate over the past few hours though a
few cumulus and mid level clouds remain across portions of the
southwest part of the CWA and in the vicinity of the I 64
corridor. Convection this evening has remained over portions of
middle and eastern Tn to the NC mountains within a moisture/PW
gradient. with weak sfc high pressure generally remaining dominant
across eastern KY. Broad troughing remains across the eastern
Conus though with generally westerly flow aloft at 500 mb though
winds are a bit more southwesterly closer to the sfc at 700 mb and
850 mb. Further west and northwest of the area, a sfc low was
tracking across the southern Great Lakes with a trailing cold
front only making slow southeast progress. However, with the sfc
high moving southeast of the area overnight, winds at least at 850
mb should become more south to southwest overnight and toward
dawn. This should lead to the moisture gradient inching into the
TN border counties overnight and lead to an increase in cloud
cover and the possibility of isolated convection in the Harlan
County to VA border corridor before dawn. Further moisture
advection on Friday will lead to additional chances for
convection across the CWA, mainly during the afternoon into the
evening. Locations further north and northeast should once again
experience valley fog under mostly clear skies and light winds as
the pressure gradient at the sfc will remain rather weak.
&&
.SHORT TERM...(This evening through Friday night)
Issued at 308 PM EDT THU AUG 25 2022
An upper trough over the eastern CONUS has begun to lift northward
this afternoon, producing seasonably warm and humid conditions
throughout eastern Kentucky. Concurrently, upper level ridging over
the Rockies and Plains has started to propagate eastward, further
aiding the height rises. To the south of the region, a shortwave
disturbance has lifted a frontal boundary from the Gulf States into
the lower Blue Ridge/Smokies this afternoon. Over the region, there
is quasi-zonal flow aloft and light southerly flow at the surface.
An embedded upstream shortwave and surface front will drop from the
Midwest into the Ohio Valley late tonight through Friday, which
could bring isolated to scattered showers/storms during the
latter half of the short term period.
Mostly quiet conditions are in place across eastern Kentucky this
afternoon, with temperatures currently sitting in the mid 80s. A
line of upslope showers has formed along the lower Blue
Ridge/Smokies early this afternoon. Additionally, a few stray
showers and storms have begun to bubble up over far western Kentucky
and southeastern Tennessee.
Weak southerly return flow has caused a cu deck to infiltrate the
southern half of the CWA. Despite the influx of cloud cover, the
area is expected to remain dry for the remainder of the day and
through the evening hours. Heading into the evening, the diurnal cu
should begin to dissipate after daytime heating is lost. Valley
fog is likely to form again tonight, but due to the moisture
inflow from the aforementioned southerly winds, the intensity and
coverage is forecast to be less than previous nights.
A cold front approaching from the Midwest will cause an uptick in
cloud coverage and PoPs starting early Friday AM, with increasing
chances of PoPs (30 to 40 percent) through the afternoon/evening
hours. Showers and thunderstorms are most likely to occur between
18z and 00z, before dying off shortly after and exiting.
Friday`s highs are forecast to reach the mid 80s, with lows
ranging from the low to mid 60s.
.LONG TERM...(Saturday through Thursday)
Issued at 325 PM EDT THU AUG 25 2022
Upper level ridging will be in place across the Southeast and will
extend northward through the Ohio Valley and into the upper Great
Lakes. This will support high pressure at the surface which will in
turn, keep conditions across the area mostly dry. There will still
be a slight chance for showers and thunderstorms mainly along the
higher terrain in the south/southwest during Saturday and Sunday
afternoon when the greatest heating is expected. Temperatures are
expected to be a few degrees warmer Sunday afternoon which may lead
to a few more showers/storms but without any large scale forcing
mechanism, these should remain widely scattered. Surface high
pressure will also be building over the Midwest which will help
support drier and much warmer conditions over the weekend. Highs are
expected to rise into the mid 80s to around 90 with dew points in
the mid to upper 60s. Conditions will be warm but should avoid being
unbearably muggy with lower dew points. Lows will fall into the low
to mid 60s Saturday night and the mid to upper 60s Sunday night.
The start of next week will usher in another pattern change as the
ridging breaks down and disturbances move through the upper levels.
Southerly/southwesterly return flow will increase as the surface
high shifts to the southwest, near the North carolina/Virginia
border. This will advect moisture from the Gulf northward into the
Tennessee and Ohio Valleys. PWAT values will increase to between 1.5
and 2 inches on Monday and will remain near that range through the
middle of the week. At the surface, a cold front will sit over the
northern Plains and will progress through the mid Mississippi Valley
and Midwest. Models do show some disagreement in the cold fronts
progression with the ECMWF being more progressive with its movement
and the GFS having the front stall out to our north, along the
southern Ohio Valley. Regardless, unsettled weather is expected with
showers and thunderstorms possible late Sunday night through
Wednesday night with the best chances for precipitation occurring
during the afternoon and evening hours. Highs Monday and Tuesday
will top out in the mid to upper 80s while overnight lows stay a bit
warmer, in upper 60s, as moisture increases across the area.
Wednesday will be a bit cooler with highs only reaching into the low
80s across most of the area.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
ISSUED AT 835 PM EDT THU AUG 25 2022
VFR was reported at issuance time and will largely prevail over
the first 6 hours of the period. However, some deeper valley fog
should develop by 4Z and increase in coverage overnight though an
increase in low and mid clouds should result in fog becoming less
prevalent toward 12Z in the Cumberland Valley as compared to the
Liking, Big Sandy, and Kentucky River basins. Reductions in valley
fog may be as low as the IFR or lower range at least at times
during the 6Z to 13Z timeframe. Brief reductions to MVFR or lower
could occur at some of the TAF sites between 8Z and 13Z, but
confidence in this is lower than average. For now have some MVFR
at LOZ which may be far enough north to be less affected by an
increase in low clouds anticipated after 6Z near the TN border,
with SJS and SME having a bit better chance of some brief
reductions during the 9Z to 13Z period as compared to JKL and SYM.
Any fog should lift and dissipate by 13Z to 14Z.
Otherwise, some cumulus should develop by around 15Z or 16Z as
moisture advection occurs ahead of a cold front and mid level
clouds are also likely. Isolated to scattered convection is
anticipated to develop by the last 6 hours of the period. Any of
this could result in brief MVFR or lower reductions.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...LUEHRS
LONG TERM...BATZ
AVIATION...JP
Area Forecast Discussion
National Weather Service Marquette MI
813 PM EDT Thu Aug 25 2022
.SHORT TERM...(Through tonight)
Issued at 309 PM EDT THU AUG 25 2022
Water vapor imagery and RAP analysis show a western ridge eastern
trof configuration across N America. Shortwave swinging thru the
trof aided shra and a few isold tsra across Upper MI over the last
24hrs. Locally hvy rainfall occurred with the most notable rainfall
in a stripe across southern Schoolcraft County last night/early this
morning where radar estimated 3.5 to more than 8 inches of rain. A
rain gauge was located that backed up the over 8 inch radar
estimation. Given the largely swampy land and very limited terrain
elevation change in that area, there was no doubt a considerable
amount of standing water, and probably quite a bit remains. With
little population in that area, have not been able to obtain any
reports of impacts from the hvy rain. With departure of the
shortwave, shra have ended from nw to se today. However, ocnl -dz
has been noted in the n wind upslope areas of n central Upper MI.
Some partial clearing has occured over western Upper MI.
Lake breeze component to the wind is currently leading to a
convergence zone from near CMX ssw across western Upper MI. With
clouds along that zone developing modest vertical extent, not out of
the question that a -shra or a few sprinkles could briefly develop
out of that. To the e and s, a few -shra may still develop across
the s central and eastern fcst area over the next few hrs. Finally,
sporadic -dz may linger for a little longer in the upslope areas of
n central Upper MI. Otherwise, in the nw flow toward the Upper Great
Lakes, a shortwave is noted over northern Manitoba. This wave is
producing a few shra in Manitoba, and earlier today, some tsra were
occurring as well. Some of this shra activity will approach Lake
Superior tonight, but with the modest low-level jet associated with
the shortwave and 850mb theta-e gradient both remaining off to the
nw thru the night, don`t anticipate any shra activity spreading out
over Lake Superior. Sfc high pres ridge currently extending from the
Dakotas across northern Ontario will shift se and will cut across
Upper MI by 12z Fri. With the rainfall that has occurred and the
lack of strong drying today, expect some fog development tonight, at
least across the interior w half of Upper MI which will end up under
the ridge axis later tonight. In addition, we`re now into the more
favorable longer nights of late summer when fog development more
frequently occurs around streams/rivers/inland lakes and swampy
areas due to their relatively warm water. Fog could be locally
dense. Expect min temps in the 40s F across the interior w half,
ranging up into the 50s F elsewhere.
.LONG TERM...(Friday through Thursday)
Issued at 253 PM EDT THU AUG 25 2022
Long term period on Friday looks to start off with a big ole surface
high sitting on top of the Upper Great Lakes. 850mb temps look to
range between 8 and 12C across the forecast area. This, coincident
with mostly clear skies early on, should enable daytime temps to
warm into the mid to upper 70s in the west and low to mid 70s in the
east. Lingering moisture with the dinural heating should support
fairweather cumulus clouds by afternoon and weak pressure gradient
should support lake breezes as well.
The high will shift into the lower and eastern Great Lakes Friday
night and Saturday. At this point, winds will become southerly along
the high`s western flank and ahead of an approaching disturbance
from the west. This will usher in a warmer and more moist airmass
for the weekend which could support periods of showers and
thunderstorms Saturday night and Sunday. Activity looks mainly
focused in the west half and over Lake Superior, but activity
elsewhere can`t be ruled out. Additionally, an increasing LLJ is
expected during the day Saturday could support some gusty winds.
Mixing could bring down 20mph winds, with parts of Gogebic County
potentially seeing some 30mph gusts. As the LLJ amplifies with the
setting sun Saturday night, downslope areas like western Gogebic and
near the lakeshores of Marquette County should expect to continue
some of these gusty winds at times. Most folks should expect temps
to top out near 80F on Saturday and low-mid 80s on Sunday. Overnight
lows look largely in the low-mid 60s. The more humid conditions are
expected to begin Sunday and Monday as the shortwave lifts into
Ontario, another moves into the northern Plains, and another lifts
northeast through Lake Michigan. There`s some uncertainty where the
latter will move through Lake Michigan, but its possible we could
see another wave of precip Monday ahead of the next wave tied to a
cold front. The cold front looks to move through Tuesday, with
cooler and drier air filtering in by late Tuesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 813 PM EDT THU AUG 25 2022
Lingering low level moisture is contributing to continued MVFR
conditions at KIWD and KSAW this evening and do not expect that to
improve with the potential for radiation fog late tonight under calm
winds. For now, will only bring visibilities down to MVFR at
KIWD/KSAW late tonight, but would not rule out possible IFR or worse
with future TAF updates for the Fri 08-12Z time frame. Any fog that
does form though is expected to dissipate after sunrise. At KCMX,
however, conditions are already at VFR levels and are expected to
stay there. As mentioned above, winds will become calm overnight.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 253 PM EDT THU AUG 25 2022
High pressure begins to dominate the region today, ushering in a
period of light winds through at least early Saturday. As this high
pressure system shifts east to the Lower Great Lakes Friday night,
SW winds will increase Saturday afternoon through Sunday. The lake
is nearing its seasonal max temperatures, so low-level stability may
not cap the strongest winds from reaching the sfc. As a 40 kt low-
level jet passes over the western half of the lake Saturday night,
some 30 knot wind gusts will be possible Saturday night through
Sunday afternoon - this is especially true at higher observation
platforms.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Rolfson
LONG TERM...JTP
AVIATION...TDUD
MARINE...JTP
Area Forecast Discussion
National Weather Service Pueblo CO
324 PM MDT Thu Aug 25 2022
.SHORT TERM...(This evening through Friday)
Issued at 324 PM MDT Thu Aug 25 2022
...Thunderstorms over the higher terrain today, better chance of
thunderstorms over all areas tomorrow...
Key messages:
1) Isolated to scattered thunderstorms will develop later this
afternoon over the mountains, and a few of these storms will move
over into the high mountain valleys and San Luis Valley.
2) PM thunderstorms will develop over the mountains and then move
over into the San Luis Valley and I-25 corridor during the late
afternoon and eastern plains by later in the evening.
3) There is a slight risk of a stronger or possibly severe
thunderstorm over the southeastern plains by late afternoon
tomorrow. Main threat will be strong and gusty outflow winds to 50
mph or greater, and hail up to 1 inch in diameter.
Detailed discussion:
Currently...
Most of the thunderstorm development this afternoon has remained
over the northern Continental Divide and an SPS has been issued for
streamflow already for the southern Chalk Cliffs area due to some
stronger thunderstorms which have remained nearly stationary over
the area. This will continue to be the area most closely monitored
throughout the afternoon. The La Garita Mountains, as well as the
San Juans, and southern Sangre de Cristo Mountains are also seeing a
fair amount of convection currently building over the area, and some
of these could get hung up on the mountains and cause concern for
possible flash flooding for some of the burn scars. There are also
some storms developing over Teller County and the Rampart
Range/Pikes peak area. This could dirft over into the northern I-25
corridor and there is a slight chance that some of these storms
could be on the stronger side for the next couple of hours. Other
than torrential rainfall with some of the stronger storms, there
could also be some gusty outflow winds to around 40 mph, as well as
small hail and cloud to ground lightning. Thunderstorms should
remained confined over the mountains for this afternoon, with only a
slight chance of a thunderstorm to move out over the adjacent plains.
Tonight...
Any remaining isolated showers and storms this evening will continue
to weaken with everything likely dissipating before midnight. One
caveat is that the HRRR is showing some isolated PoPs over the
eastern mountains in the early morning hours on Friday. The NAMNest
4km (which tends to usually be a little more aggressive with PoPs)
doesn`t show as nearly as much reflectivity in the most recent model
run. Considering this, confidence is low of there being a few
isolated showers developing early in the morning over the eastern
mountains and moving out over into the I-25 corridor with some
residual moisture advancing in from the west due to convection from
the previous day. These showers would be very high based and may not
even reach the surface (be in the form of virga) if they were to
occur. Skies otherwise should continue to break and become mostly
clear for most locations throughout the night with diurnally driven
winds expected across the entire CWA. Temperatures will cool into
the 50s for most areas of the plains, and into the 30s and 40s for
the higher terrain.
Tomorrow...
The ridge that is currently over the inner-mountain west with an
upper level high centered over northern Mexico will continue to
flatten slightly and allow for the monsoonal moisture plume at the
500 mb level to become expanded over southeast Colorado on Friday.
This will allow for thunderstorms to develop tomorrow afternoon over
the mountains initially and then move over into the upper mountain
valleys and San Luis Valley throughout afternoon and eventually into
the I-25 corridor and over the Raton Mesa by late afternoon. Expect
for storms to be possible over the eastern plains by the evening
hours as they continue to track from the west. Looking at the latest
CAMS, there still looks to be the most CAPE located over the
southern mountains, although it is a little less than previous
models have displayed, at around 1100 J/kg at best over the southern
Sangre de Cristo Mountains. The better shear and lapse rates remain
up to the north over the Sawatch and Rampart Range of around 40 kts,
with lapse rates generally between 8 and 9 C/km. However. CAPE is a
little less, especially over the Rampart Range, with the Sawatch
having the greatest at around 900 J/kg. Given these values, stronger
storms are possible, yet severe storms are not anticipated over
these areas. The stronger storms may produce some gusty outflow
winds up to 50 mph and torrential rainfall in a short period of
time, which may impact the burn scar areas if any of the storms
become hung up on the mountains and are near stationary with
respects to storm motion. As these storms move over into the I-25
corridor by later in the afternoon, some of them will likely weaken
a bit as they encounter a relatively less favorable environment
right along the I-25 corridor, the exception will be northern I-25
corridor around the Palmer Divide and the southern I-25 corridor
near Trinidad where the environment looks to be a little more
favorable to sustain better convection. There are going to be better
areas of CAPE down around the Raton Mesa area of over 1000 J/kg.
Coupled with this, the lower levels look to destabilize as a
southerly flow advects up some higher dewpoints and this may allow
for the cap to break for certain locations over the central plains
and aid in the further development of thunderstorms. Most of these
storms should remain sub-severe, however and isolated stronger or
possibly severe storm cannot be ruled out. Given the inverted-v
profile soundings over the central and eastern plains at the time,
the main threat accompanied with these storms is going to be strong
and gusty outflow winds of up to 50 mph or greater, and possible
hail up to 1 inch in diameter if the elevated core strengthens to 50
dbz or greater at or above the hail growth zone. Temperatures will
be slightly cooler and expected to be mainly in the 80s and a few
low 90s for the plains, and generally in the 70s for the upper
Arkansas River Valley and San Luis Valley, and 50s to 60s for high
country. -Stewey
.LONG TERM...(Friday night through Thursday)
Issued at 324 PM MDT Thu Aug 25 2022
Friday night-Sunday night...Latest models are fairly consistent on
modest westerly flow with an embedded short wave translating
across the region Friday night, with shortwave ridging in place
across the region on Saturday before westerly flow increases again
Saturday night and Sunday, as a stronger system translates across
the Northern Tier and Northern Rockies Sunday night.
With that said, still looks to be good chances of showers and storms
over and near the higher terrain Friday afternoon and into the early
evening, with the best chances then shifting out across the far
southeast plains, where a few stronger storms could be possible,
with convergence along lee trough/induced sfc low across the plains.
Short wave ridging on Saturday helps to stabilize the plains, though
there will be enough residual moisture to support scattered diurnal
showers and storms over and near the higher terrain. While there
remain some differences on strength and location of the Sunday
system, most models are trending further north with this system,
which could bring scattered showers and storms to areas mainly north
of the Highway 50 Corridor Sunday afternoon and evening. Time will
tell how this system evolves. As for temperatures, with the westerly
flow aloft, at or above seasonal temperatures remain the rule, with
highs expected to be in the 80s to mid 90s across the plains, and
mainly 60s and 70s across the higher terrain.
Monday-Thursday...Model differences become more evident in the
longer term forecast, as models do indicate broad upper ridging
developing across the West Coast, with broad troughing in place
across the East Coast. The GFS and Canadian runs, and to a lesser
extent the GEFS ensemble mean, keep more energy in place across the
High Plains, where as the ECMWF and the EPS ensemble mean, keep the
prominent ridge further east across the Great Basin and into western
Colorado, which would tend to keep things drier areawide. With said
differences, have stayed with current bullish NBM pops, which keeps
chances for showers and storms across the area through out the long
term forecast. As for temperatures, despite location differences of
the ridge, ensemble means are in agreement with keeping temperatures
at to slightly below seasonal levels through the period, with the
coolest readings across the plains later next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 324 PM MDT Thu Aug 25 2022
VFR conditions are expected to prevail for all TAF sites (KALS,
KCOS, and KPUB) throughout the forecast period. There could be some
SHRA and possibly TSRA in and around the vicinity of KALS throughout
the evening hours. If SHRA/TSRA does develop, it could temporarily
reduce CIGs and VIS to MVFR/IFR criteria for KALS. It could also
result in periodic windshifts and increased wind speeds at the
terminal. There is much less of a chance for convection to be in the
vicinity of KCOS and not expected to be in the vicinity of KPUB.
Winds will be diurnally driven. There will be a better chance of
convection in the vicinity of all terminals tomorrow, towards the
end of the forecast period. -Stewey
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...STEWARD
LONG TERM...MW
AVIATION...STEWARD
Area Forecast Discussion
National Weather Service San Diego CA
132 PM PDT Thu Aug 25 2022
.SYNOPSIS...
Scattered thunderstorms in the mountains and deserts will
continue through this afternoon. Moisture will continue to
decrease Friday, making thunderstorm coverage more isolated and
confined to the mountains. Cool and dry conditions for the
weekend, with a gradual warming trend from the beginning to middle
of next week.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
Forecast Highlights:
*Flood Watch in effect through tonight.
*Isolated thunderstorms in the mountains Friday.
*Warming trend Monday through the middle of next week.
As of 1 PM a few thunderstorms have developed over the mountains.
The HRRR is showing more developing through the afternoon and
drifting onto the desert mountain slopes, locally into the desert. A
Flood Watch remains in effect through tonight. Limited thunderstorm
development is expected Friday, with isolated storms expected in the
mountains.
An incoming trough moving through the northwest will keep drier,
westerly flow aloft through the weekend. Moisture levels continue
to decrease Friday, with more noticeable drying on Saturday.
Moisture will not make a comeback for the foreseeable future with
dry conditions expected Saturday through at least next Thursday.
Cooler conditions are expected over the weekend. A warming trend
will begin Monday and continue through the middle of next week. High
temperatures will peak at 5 to 10 degrees above average Wednesday
and Thursday. Closer to the coast, expect areas of night and
morning low clouds and fog to spread inland into portions of the
western valleys at times.
&&
.AVIATION...
251931Z...Coast/Valleys...SCT clouds AOA 12000 feet MSL today and
early tonight. SCT low clouds with bases 1000-1200 feet MSL and tops
to 1500 feet MSL over the coastal waters pushing ashore after 26/04Z
this evening. Low clouds extending inland to just west of KRNM and
just west of KONT also tonight into Friday. Local vis 3-5SM along
inland edge of clouds. Risk of BKN low clouds at KSAN overnight is
moderate to high. Confidence in 26/04z low cloud arrival time at
KSAN is moderate.
Mountains/Deserts...SCT locally BKN clouds AOA 12000 feet MSL
through tonight. SCT TSRA will return to mountains and deserts until
02Z today. Bases around 8000 to 10000 feet MSL and tops to 40000
feet. Gusty and erratic winds, frequent lightning and heavy
downpours will occur near TSRA.
&&
.MARINE...
No hazardous marine weather is expected through Monday.
&&
.BEACHES...
A south swell with a long period will bring elevated surf and a high
rip current risk for Friday through the weekend. The highest surf
will be on south-facing beaches, mainly in Orange County where
highest surf could reach 7 feet Saturday and Sunday.
&&
.SKYWARN...
Skywarn has been activated.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Flood Watch until 10 PM PDT this evening for Apple and Lucerne
Valleys-Coachella Valley-Riverside County Mountains-San
Bernardino County Mountains-San Diego County Deserts-San
Diego County Mountains-San Gorgonio Pass Near Banning.
PZ...None.
&&
$$
PUBLIC...CO
AVIATION/MARINE/BEACHES...Small
Area Forecast Discussion
National Weather Service San Angelo TX
647 PM CDT Thu Aug 25 2022
...New AVIATION...
.SHORT TERM...
(This evening through Friday)
Issued at 1251 PM CDT Thu Aug 25 2022
Any residual showers and storms from this afternoon, should largely
dissipate after sunset with the increase in capping from the loss of
daytime heating. Temperatures tonight will remain near normal in the
upper 60s to low 70s with generally light winds out of the
east/northeast.
Tomorrow will be very similar to today, in that if any shower/storms
do form, they will be highly isolated and generally confined to the
Northern Edwards Plateau and the I-10 corridor. Most hi-res guidance
shows little activity across the area. Looking at model soundings,
with decreasing moisture availability and a potential temperature
inversion in the mid-levels, this looks to hinder development but
there may be a few hours during afternoon peak heating where we
could see some widely isolated development. The HRRR has been the
most active with this diurnal activity with model soundings showing
a largely uncapped atmosphere through the afternoon hours. In any
case, it doesn`t look as though these will be very high topped
showers/storms with much of the available instability and moisture
generally below 600 mb. Flooding does not look to be a concern with
these storms considering a more shallow moisture profile and overall
less moisture to work with than we`ve seen over the past few days
(indicated by high morning dew points mixing out and much lower
pWats). Highs will start to creep up tomorrow afternoon with
temperatures areawide reaching into the low to mid 90s.
&&
.LONG TERM...
(Friday night through next Wednesday)
Issued at 1251 PM CDT Thu Aug 25 2022
Expect mainly dry conditions along with near seasonal temperatures
across West Central Texas this weekend. An isolated shower or
thunderstorm cannot be ruled out across our southeast counties
Saturday afternoon and across our eastern counties Sunday afternoon,
but expect mainly dry conditions to persist. Highs on Saturday will
be in the low to mid 90s, with highs on Sunday in the mid to upper
90s.
On Monday, the ECMWF strengthens an upper level ridge across the
Great Basin region, while an upper level trough/low develops across
the Rockies and slowly moves south toward New Mexico/West Texas
through the middle of the week. This would result in good rain
chances across West Central Texas, mainly beginning on Thursday. In
addition, a weak cold front is forecast to move into the region
Tuesday into Wednesday, which could result in additional lift for
shower and thunderstorm activity. The 12Z GFS has trended a bit
farther west with the aforementioned upper level low, bringing it
south toward the Panhandle, before lifting it north toward the
end of the week. Although it has trended a bit farther west, this
solution is still much drier than the ECMWF. Given the continued
uncertainty, opted to keep PoPs in the slight chance to chance
category next week. Temperatures on Monday will be in the mid to
upper 90s, but the increased cloud cover and possible showers and
thunderstorms will help to keep temperatures near to slightly
below seasonal normals for the middle to latter part of the week.
&&
.AVIATION...
(00Z TAFS)
Issued at 644 PM CDT Thu Aug 25 2022
VFR conditions expected the next 24 hours. Although a few showers
and isolated thunderstorms will be possible Friday afternoon
across the southern terminals, coverage will be too sparse to
consider mentioning in the forecast. Expect light winds the next
24 hours.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 68 93 71 95 / 0 0 0 10
San Angelo 71 93 72 95 / 10 10 0 10
Junction 70 93 71 93 / 10 10 0 20
Brownwood 70 93 72 95 / 0 10 0 10
Sweetwater 70 92 72 95 / 0 0 0 10
Ozona 70 90 71 91 / 10 20 0 10
Brady 70 92 71 93 / 10 10 0 20
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...50
LONG TERM....Daniels
AVIATION...24
For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.php