Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/24/22
Area Forecast Discussion
National Weather Service Binghamton NY
1001 PM EDT Sat Jul 23 2022
.SYNOPSIS...
Showers will taper off overnight with patchy valley fog
possible in the twin tier region. Then for Sunday, expect
another hot and humid day with isolated showers and storms in
the morning and another round in the afternoon followed by more
overnight showers and storms into Monday. Milder and drier
weather is expected by the middle of the week.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
For the remainder of this evening and overnight, a convectively
induced mesoscale wave will continue to move east across the middle
Atlantic states and weaken as it encounters diminishig instability
and low-level dry air. We will maintain some showers and a few
isolated thunderstorms into south central NY on the northern edge of
this wave around 05z-06z. After this wave passes by, skies will
clear but some higher clouds will reach NY and PA toward dawn.
Additionally, the low-level winds around 925 mb will increase to
near 20 knots from the southwest by morning. Given that we just
had some rain in the twin tiers we will go for some valley fog
again late tonight/Sunday morning.
Then for Sunday morning, MCS over the Great Lakes and
associated convectively induced wave moves across NY/PA and is
weakening. HRRR and NAMnest suggest convection over Lake
Michigan at this time weakens enough that it won`t be more than
a light shower Sunday morning. The low-level winds will continue
to increase Sunday and by afternoon, low-level moisture will
surge into central NY and northeast PA. This will occur during
maximum heating and with dewpoints projected to be around 70F
and maximums from upper 80s to mid 90s we once again have heat
advisories for our warmer parts of our CWA. This is pretty much
all areas except our more mountainous counties. With this heat
and low-level moisture, mixed layer CAPEs are projected to be
around 2000 J/KG or higher Sunday afternoon. The NAM and GFS
both have a capping inversion late in the morning/early
afternoon which will break due to heating and also the arrival
of another convectively induced wave from the MCS over IA and NE
at this time as per CAMS models. The NAMnest develops a decent
looking line of storms Sunday afternoon with the HRRR a bit
weaker. This first batch of storms could become severe given the
strong shear profiles and high CAPE and we concur with the
slight risk for severe thunderstorms in our area. There is
definitely uncertainty though, as we are banking on a
convective wave to trigger the activity in the afternoon and we
know that models struggle with said features.
Then after this first batch of showers and thunderstorms moves by,
an upper level low will reach James Bay Canada Sunday night and lead
to lower surface pressures across Ontario and Quebec. At the
same time, the large upper level anticyclone near Bermuda will
remain put increasing the pressure gradient through the depths
of the troposphere Sunday evening and night over the northeast
U.S. Strong low-level moisture advection will be helped along by
an intense low-level jet of around 50 to 60 knots from the
southwest by 06z Monday. This low-level jet over the northeast
U.S will feed into a right entrance region of an upper level jet
over southeast Canada. NAM model soundings also show
significant CAPE Sunday night, GFS is much less on CAPE Sunday
night. Precipitable water values will be approaching 2" so in
addition to the potential for severe storms Sunday evening,
there could be some locally heavy rainfall. Since we are in the
beginnings of a drought, this could be some beneficial rains
for many areas. Of course there could be some problems in our
urban areas. CAMS are showing locally between 2" and 4" of
rain in a band. It will depend on how much instability will
remain Sunday evening. For now will mention potential for SVR
and locally heavy rain in HWO.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
305 PM update...
The cold front continues to slowly track southeast through the area
Monday, possibly even stalling out somewhere across our southeastern
zones as the upper trough closes off into a cutoff low over Quebec.
The left exit region of an albeit weak upper jet will be moving over
the region, possibly lending some additional dynamical support as
the front moves through to enhance rainfall rates into the
afternoon. Meanwhile, PWATs remain anomalously high at up to 1.75in
into the daytime Monday. This is all to say that we could continue
to pick up on decent rainfall totals before the front finally drops
south of the area into Monday evening.
A much drier airmass will be in place behind the cold front,
allowing skies to quickly clear out while a ridge begins to build
over the region. This will help to keep things dry through Tuesday
and at least through Tuesday night.
Otherwise, temperatures remain more or less seasonal through the
short term, with afternoon highs generally in the 80s both days and
lows in the 50s to lower 60s both nights. Tuesday will be
comparatively less humid, with dewpoints in the 60s Monday falling
into the 50s for Tuesday.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
305 PM update
Wet and unsettled weather will return for the remainder of the
forecast period. Wednesday, the upper ridge begins to move out,
while a sprawling upper low moves over Ontario. This will touch off
a period of warm air advection into Wednesday, and thus chances for
showers and thunderstorms work back in. There may be better
dynamical support to enhance precip chances into Thursday as a weak
shortwave rotates around the parent upper low still to our
northwest. The upper trough finally begins to dig in later thursday
into Friday, with an approaching cold front keeping in chances for
showers and storms through most of Friday before the cold front
finally moves through into the evening. However, there are
differences in the timing of the frontal passage among the
deterministic and model guidance, with some runs showing passage and
the heaviest QPF earlier in the day. PWATs will also run high again,
with many of the ensemble members showing values as high as 1.25 to
1.75 inches.
Temperatures stay seasonal for much of the period, though Wednesday
and Wednesday night will be a few degrees warmer than average with
decent warm air advection due to increasing southwesterly flow
behind the exiting ridge.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
Expecting mainly VFR conditions overnight all terminals. There
were showers in the twin-tier region that were beginning to
fizzle out. KBGM and KELM were already affected by these showers
and storms and this activity should remain in between KBGM/KELM
and KAVP. So we don`t have any restrictions at KAVP. Farther
north, KITH, KSYR and KRME should be in the clear as far as
restrictions go into the night. There could be a little fog that
forms in the valleys late tonight. The 925 mb winds are
projected to be around 15-20 knots from the west-southwest.
Visible satellite imagery suggests some higher clouds work in
later tonight so not an optimal valley fog night. We put a tempo
for IFR in BR at KELM 09-13z but there is quite a bit of
uncertainity here.
Then for Sunday, expecting a line of showers and thunderstorms
to cross all terminals between 18z and 00z Monday. For now, we
have MVFR conditions with these storms as considerable
uncertainty exists as to how widespread or if an individual
terminal gets hit directly or not.
Winds will be primarily west to southwest under 10 knots
overnight and around 10 knots with gusts to 20 knots or so by
Sunday afternoon.
Outlook...
Sunday night through Monday...Possible restrictions in showers
and thunderstorms. Most likely time Sunday afternoon through
early Monday morning.
Monday night through Wednesday...mainly VFR. Possible valley
fog at ELM.
Thursday...Next chance of showers and storms with associated
restrictions possible.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...Heat Advisory from 1 PM to 7 PM EDT Sunday for PAZ044-047.
NY...Heat Advisory from 1 PM to 7 PM EDT Sunday for NYZ016>018-
023>025-036-037-055-056.
&&
$$
SYNOPSIS...BJT/DJN
NEAR TERM...DJN
SHORT TERM...HLC
LONG TERM...HLC
AVIATION...DJN
Area Forecast Discussion
National Weather Service Birmingham AL
652 PM CDT Sat Jul 23 2022
.UPDATE...
For 00Z Aviation.
&&
.SHORT TERM...
/Updated at 0103 PM CDT Sat Jul 23 2022/
Central Alabama will remain under a southwesterly flow at the
surface through the rest of the day today with very moist and
humid conditions. Showers and storms have developed mostly across
the southwestern counties early this afternoon as expected. The
old MCV that affected our weather yesterday is still currently
spinning just to our west in Central Mississippi. Storms on the
east side of the MCV will continue to move northeastward as we go
through the afternoon. Fortunately, the 12z KBMX sounding,
including current RAP analysis presents a more stable environment
today, especially aloft with moist-adiabatic lapse rates and
warmer temps at 500mb. Although the overall microburst potential
is much lower today, tropical showers and storms will be capable
of gusty winds at times with torrential rainfall and frequent
lightning through the afternoon. There is enough shear aloft to
keep updrafts sustained a bit longer, so we`ll watch for the
potential of a few strong storms this afternoon. Mesoscale
boundary interactions will continue to trigger showers and storms
as we go into the early evening hours before diminishing with the
loss of daytime heating. Highest rain chances will remain across
the southern half of Central Alabama.
Muggy conditions are expected again overnight with indications
that we may not see as much in the way of low clouds or fog like
what was observed this morning. If we`re able to get a bit more
widespread thunderstorm development this afternoon and evening we
could see more patchy fog in those locations. At this point fog
has not been added to the forecast as of yet due to low
confidence of development. We should see almost a rinse and repeat
forecast for Sunday, and perhaps a touch warmer in terms of
afternoon highs. Heat indices will once again rise above 100
degrees in many spots, possibly going as high as 103. Not reaching
advisory criteria, but still very oppressive for folks who have
outdoor activities planned. We`ll continue to keep mention of heat
in the HWO due to a few localized spots that may get close to 105
Sunday afternoon. At least scattered showers and storms remain in
the forecast during the afternoon, and we could see a very
similar setup to today in terms of storms developing along
mesoscale boundaries that could be more widespread at times.
56/GDG
.LONG TERM...
/Updated at 0333 PM CDT Sat Jul 23 2022/
Made a few adjustments to rain chances from mid week through the
end of the forecast period. The upper level ridge becomes messy by
Tuesday due to the influence of a weak inverted trough moving
westward across the Gulf Coast. This could provide a better focus
for development across our east and southeastern counties. For now
will maintain highest rain chances across the northeast, where
moisture and weak convergence is greater. A brief strengthening of
the ridge occurs ahead of an approaching trough and front, with
heat indices near or above 105F for most of the area on Thursday.
Guidance continues to support likely pops on Friday and Saturday.
14
Previous long-term discussion:
/Updated at 0314 AM CDT Sat Jul 23 2022/
Monday through Saturday.
Despite an expansive 500mb ridge across the Gulf Coast States,
there is a weakness in the ridge over Alabama. With PWATs expected
to remain around two inches, scattered diurnal thunderstorms will
develop Monday and Tuesday. By Wednesday, a broad upper trof
begins to sink southward from the Great Lakes region. This will
cause the upper ridge over the Gulf Coast to strengthen temporarily
and rain chances will decrease. By Thursday, the upper trof will get
close enough to north Alabama for an increase in rain chances
areawide. Rain chances really ramp up Friday and Saturday as the
trof axis continues to dig southward, and increased rain chances
to likely category for both days. Heat indices will be the highest
on Wednesday and Thursday, where values could reach 105 degrees in
many areas.
58/rose
&&
.AVIATION...
00Z TAF Discussion.
Will continue the trend of mentioning less in the way of low
clouds and fog than occurred this morning. Overall, less
convection and a day of drying ground conditions. Therefore, VFR
will be the predominant condition. Afternoon showers and
thunderstorms are possible and will be scattered in nature. PROB30
mentioned at all terminals. Winds remain light and variable
overnight and staying light southwest on Sunday.
75
&&
.FIRE WEATHER...
Mainly afternoon scattered showers and storms to remain possible
through early next week. Southwesterly to southerly surface and
transport wind at 5-10 mph will continue. Minimum RH values remain
above 45%. Excessive heat conditions are also expected for much
of the area with heat index values 105 to 110 degrees at times
from Sunday through at least Thursday.
&&
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 71 93 71 92 71 / 20 30 20 30 20
Anniston 73 93 72 92 73 / 20 30 20 30 20
Birmingham 74 93 75 92 74 / 20 30 20 30 20
Tuscaloosa 73 94 75 94 74 / 20 30 20 30 20
Calera 73 92 74 92 74 / 20 30 20 30 20
Auburn 73 92 72 91 73 / 20 40 20 40 20
Montgomery 74 95 75 94 74 / 20 40 20 40 20
Troy 73 94 72 93 72 / 20 40 20 50 20
&&
.BMX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Boston/Norton MA
927 PM EDT Sat Jul 23 2022
.SYNOPSIS...
Very hot with near record heat Sunday, then oppressive humidity
returns Sunday night and Monday. Scattered showers and thunderstorms
arrive Monday, especially in the afternoon and evening, as a
cold front approaches. Some of the storms may be strong to
severe, along with heavy downpours. The heat wave then breaks,
with much lower humidity Tuesday and Wednesday, along with dry
and seasonably warm conditions. Another frontal system brings a
chance of showers and thunderstorms Thursday and/or Friday.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
925 PM update...
Weakening convection to the west with some mid/high clouds
moving into SNE tonight. Otherwise, stratus and fog bank lurking
around ACK and with SW flow this is not likely to advect much
further W. HREF probs suggesting some stratus potentially
developing over Buzzards Bay and advecting onshore overnight.
A rather warm evening in progress with temps still upper 70s to
mid 80s with expected lows in the low/mid 70s for much of SNE.
Current forecast on track.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
Highlights
* Dangerous heat continues on Sunday with not much relief Sunday
night as low temps will be in the 70s for most. May even see
some upper 70s for urban centers. Several climate spots could
see record daily highs and perhaps warmest low temps. See the
climate section below for more details.
* Could see a few isolated showers/storms pop up across the
interior during the afternoon. Risk higher for showers/storms
to spread into W/NW areas late in afternoon/evening from
Upstate NY.
Remain under cyclonic flow through this period with a shortwave
lifting from the central Great Lakes Sunday AM into the eastern
Great Lakes by the afternoon. By Sunday evening this shortwave
lifts into northern New England. Will have a surface trough in
place over our region for much of the day, while a cold front
slides across the central Great Lakes into the eastern Great
Lakes by late Sunday night.
Main concern during this period is the oppressive heat/humidity
across southern New England. Current Heat Advisory looks good.
Will actually peak temperature wise in this stretch of hot
weather on Sunday as 850 hPa temps warm to 19-22 degrees
Celsius. Fortunately will see strong mixing within the boundary
layer that will also bring dew points down a bit. Given the
heats performance today went with the 80th percentile of
guidance for highs, while lowering dew points toward the HREF
and other blended guidance. Should see dew points in the
afternoon in the mid 60s for most with some upper 60s to low 70s
toward the south coast. At this point am expecting widespread
highs in the 90s away from the south coast. May struggle given
the onshore flow to get into the 90s, but will at least be in
the mid/upper 80s. Lastly, do have a few spots approaching or at
100 degrees across the CT and Merrimack Valley. Expect most of
our southern New England climate sites to threaten if not break
the daily temperature record for July 24th. See the climate
section below for more details. The combination of the heat and
humidity will result in Heat Index values ranging from 95 to
104. Those with outdoor plans will want to stay hydrated.
Did bump up wind speeds/gusts through the period given the 30-50
kt SW low level jet moving in late on Sunday into early Monday.
Leaned toward the NAMNest/ARW/FV3 guidance as it tends to do
better in well mixed scenarios. Given we will be well mixed will
be quite difficult for the sea breeze to provide relief for
eastern coastal areas.
Lastly, does appear there could be some pop up showers/storms
across the interior during the afternoon as CAMs show. Given the
strong diurnal heating, sufficient dew points and instability
of roughly a few hundred J/kg of MLCAPE. Could perhaps see a few
pop up showers/storms. Though for now think this activity will
be limited given the dry mid level air and strong mixing within
the boundary layer. Think the risk of showers/storms is higher
from the activity pushing in late in the day and especially
Sunday evening. The question will be the timing as instability
wanes, but deep layer shear in the 0-6 km layer increases to
25-35 kts late. Think the latest SPC Outlook for Day 2 is
reasonable with marginal risk across western portions of the
region given the increasing shear late. Will be something we
need to keep an eye on late in the day. Think the main risk with
any stronger storms would be strong wind gusts given the DCAPE
values of a few hundred J/kg and somewhat of an inverted V
sounding shape per the RAP/NAM/GFS in Bufkit. This is also the
risk highlighted by the last few runs of the NCAR HRRR Neural
Network Convective Hazard Forecast.
Not much relief Sunday night into early Monday with us still
being well mixed in southwesterly flow and increasing dew
points. Lows will remain well into the 70s with urban centers in
the upper 70s.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
330 PM update...
Highlights
* Not as hot Monday but oppressive humidity combined with highs of
85-90, will yield very warm & uncomfortable conditions
* A cold front Monday brings scattered showers & storms, some strong
to severe, along with locally heavy downpours
* Heat wave breaks with gorgeous weather Tue and Wed, featuring dry
and seasonably warm conditions, but much lower humidity
Details...
Monday...
Core of excessive heat plume begins to move offshore Monday, as
height falls associated with upstream trough approach SNE. Although,
given a very warm start to the day (morning lows only in the 70s)
combined with +19C at 850 mb at 18z Monday, and +23C at 925 mb or
higher may yield another 90+ day for parts of the region, with
highest prob from interior CT/RI into eastern MA. That would make it
day 7 for the heat wave in many locations! Thus, highs of upper 80s
to lower 90s seems reasonable, cooler south coast given SW winds.
Despite temps not quite as hot Monday as Sunday, it will be very
uncomfortable Monday with high dew pts, in the low to mid 70s(!)
resulting in oppressive humidity. This may push heat indices into
the mid and upper 90s across the region mentioned above. Hence, the
heat advisory may need to be extended into Monday for portions of
the area. As previous forecaster noted, a modest low level SW jet
will provide breezy conditions. SW winds 15-25 mph, with highest
gusts over SE MA. Thus, the breeze will help Monday, nonetheless, a
very uncomfortable day.
As for chances of showers/thunderstorms, robust northern stream
short wave tracks across southern Quebec. As previous forecaster
noted, bulk of forcing for ascent tracks across northern New
England. However, appears sufficient trailing short wave energy
moving across the Great Lakes and eventually into SNE Monday
afternoon and evening, to provide forcing for ascent. Shear and
instability profiles from the ensembles are robust, with about 45 kt
of flow at 500 mb over SNE Mon afternoon/evening, along with 90-100%
probs for CAPEs to exceed 1000 j/kg and 40-50% probs of CAPEs
exceeding 2000 j/kg! So despite forcing for ascent somewhat weak,
thinking cyclonic flow with around 45 kt of mid level flow, combined
with 1000-2000 j/kg of CAPE, along with enhanced QG forcing from RR
quad of upper level jet, should be sufficient for a fairly strong
atmospheric response. Thus, thinking scattered to perhaps numerous
showers/t-storms, with at least a few strong to perhaps severe
storms possible. Furthermore, CIPS and CSU severe wx progs support
this scenario, as well as slight risk from SPC. Main hazards with
storms will be strong winds (given winds aloft), large hail (up to
2000 j/kg CAPE) and isolated flood threat (PWATs up to 150% of
normal).
Tuesday and Wednesday...
Pick of the week! Post frontal airmass, not as hot, seasonably warm
with highs in the 80s, and much more comfortable with dew pts in the
50s (low to mid 60s along the coast). Lows Tue night/Wed morning in
the mid to upper 50s across western-central MA, 60s elsewhere.
Fantastic days for outdoor activities, enjoy!
Thursday/Friday/Saturday...
Warmer and more humid Thu and Fri along with a chance of showers/T-
storms ahead of next short wave trough/cold front. Trending drier
and not as hot Saturday.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
00Z update...High confidence except lower confidence on areal
coverage and duration of IFR/LIFR conditions overnight at ACK.
Mainly VFR overnight with SW winds. Although deck of stratus
just south of Nantucket will likely impact the island for at
least a portion of the night. IFR/LIFR conditions possibly
impacting KMVY and Cape Cod at times overnight. Earlier
discussion below.
============================================================
Sunday...High confidence.
VFR with a few isolated showers/storms spreading into the
interior during the afternoon/evening. Should see any lingering
low clouds/stratus burn off for the Cape/Islands by 13-15Z. Increasing
SW winds with gusts to 25 kt developing during the afternoon.
Sunday night...High confidence.
VFR for much of the region other than the Cape/Islands where
IFR to LIFR stratus/fog spreads in. Could perhaps see a few
showers/storms across the interior. If a storm passes over a
terminal could see conditions lowering to MVFR/IFR limits, but
confidence not high enough to include in the TAF at this time.
Winds out of the SW at 10-20 kts with gusts of 15-25 kts. Expect
the highest speeds/gusts over the Cape/Islands.
KBOS...High confidence in TAF.
KBDL...High confidence in TAF.
Outlook /Monday through Thursday/...
Monday through Monday Night: VFR. Breezy. Scattered SHRA,
isolated TSRA.
Tuesday through Wednesday: VFR.
Wednesday Night: Mainly VFR, with local MVFR possible. Isolated
SHRA, isolated TSRA.
Thursday: Mainly MVFR, with areas VFR possible. Scattered SHRA,
isolated TSRA.
&&
.MARINE...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.
Have hoisted a SCA Sunday afternoon through Monday for much of
the waters due to increasing SW winds/gusts and seas.
Tonight...High confidence.
Winds out of the S/SW between 10-15 kts tonight. Seas 2-4 ft.
Main issue will be the low clouds and fog along the south coast.
Fog may be dense at times around and east of Nantucket.
Sunday and Sunday night...High confidence.
Increasing S/SSW winds especially late on Sunday and Sunday
night. Will see wind speeds of 15-20 kts by the afternoon and
persisting overnight. Wind gusts of 25-30 kts by late
afternoon and overnight. Seas build to 3-6 ft across the outer
waters by late afternoon and 3-7 ft overnight. Should see the
3-6 feet spreading into the southern inner waters by the
evening. Another round of low clouds/fog across the southern
coastal waters.
Outlook /Monday through Thursday/...
Monday: Moderate risk for Small Craft Advisory winds with gusts
up to 25 kt. Rough seas up to 8 ft. Scattered rain showers,
isolated thunderstorms.
Monday Night: Low risk for Small Craft Advisory winds with
gusts up to 25 kt. Areas of rough seas. Numerous rain showers,
isolated thunderstorms, patchy fog.
Tuesday: Winds less than 25 kt. Areas of seas approaching 5 ft.
Isolated rain showers, isolated thunderstorms.
Tuesday Night: Winds less than 25 kt. Areas of seas approaching
5 ft.
Wednesday: Winds less than 25 kt.
Wednesday Night: Winds less than 25 kt. Isolated rain showers,
isolated thunderstorms.
Thursday: Winds less than 25 kt. Seas locally approaching 5 ft.
Isolated rain showers, isolated thunderstorms.
&&
.CLIMATE...
Record Daily High Temperatures
July 23
BOS...100 in 1952
BDL... 99 in 1978
PVD... 97 in 1918 and 1978
ORH... 96 in 1952
July 24
BOS...98 in 1933
BDL...96 in 1987
PVD...94 in 1933 and 1987
ORH...94 in 1910
Record Daily Warmest Low Temperatures
July 23
BOS...76 in 1955
BDL...74 in 1972
PVD...78 in 1978
ORH...75 in 1918
July 24
BOS...74 in 1935 and 1991
BDL...76 in 1961
PVD...74 in 1935
ORH...72 in 1935
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...Heat Advisory until 8 PM EDT Sunday for CTZ002>004.
MA...Heat Advisory until 8 PM EDT Sunday for MAZ005>007-011-013>022.
Heat Advisory from 10 AM to 8 PM EDT Sunday for MAZ002>004-
008>010-012-026.
Air Quality Alert until 11 PM EDT this evening for MAZ007-
020>022.
RI...Heat Advisory until 8 PM EDT Sunday for RIZ001>007.
Air Quality Alert until 11 PM EDT this evening for RIZ006-007.
MARINE...Small Craft Advisory from 2 PM Sunday to 8 PM EDT Monday for
ANZ231>235-237-250-254>256.
&&
$$
SYNOPSIS...Nocera/BL
NEAR TERM...KJC
SHORT TERM...BL
LONG TERM...Nocera
AVIATION...Nocera/BL
MARINE...Nocera/BL
CLIMATE...
Area Forecast Discussion
National Weather Service Cleveland OH
1021 PM EDT Sat Jul 23 2022
.SYNOPSIS...
An active warm front lifts across the area overnight tonight
into early Sunday. This is followed by a cold front Sunday
evening into Sunday night. High pressure follows for early in
the week as the cold front stalls across the Ohio Valley. The
next system will arrive towards midweek.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
An MCS is approaching the Grand Rapids metro and will continue
generally just south of east through lower Michigan. The complex
does extend southwest across Lake Michigan and this portion of
the line seems to be surging more southeast and should broach
Lucas County and western Lake Erie after 1 AM. However, the
atmosphere this MCS is entering is fairly unfavorable with ample
CIN, suggesting a stable environment. Recent HRRR runs have this
feature falling apart around Lake Erie, which isn`t
unreasonable. With this, have maintained just likely PoPs across
the northern portions of the forecast area overnight - timed
with the current radar.
Portions of Previous Discussion...
Prototypical late-July MCS pattern leading to a continued tricky
forecast through the remainder of the weekend. The main concern
is Sunday afternoon and evening, when a Slight Risk for severe
weather exists across the entire area, to go along with some
potential for locally heavy rain as well. However, some
thunderstorms are possible overnight tonight into early Sunday,
with non-zero potential for some impacts from those as well.
A warm frontal zone will lift across the area overnight
tonight, with a potent convectively- enhanced shortwave
currently over MN and IA moving by overnight. This shortwave
will provide a brief period of enhanced lift overnight tonight,
which will likely allow for at least scattered showers and
storms to re-develop near the warm front late this evening into
the overnight. This front gradually lifts through and out of the
area by Sunday morning. Along with the warm frontal passage,
the aforementioned shortwave over the upper Midwest is driving
an MCS this afternoon, and whatever is left of this will try to
drop towards northern Ohio overnight tonight as well. Overall,
have chances peaking briefly at high chance to low likely
(40-60%) across the area overnight, as there`s a fair amount of
uncertainty thanks to an ongoing MCS near the warm front over
central IL this afternoon casting some doubt regarding how well
moisture and instability can return into tonight. If this
activity dissipates quickly over the next few hours, it would
likely point to greater potential for a round of overnight
showers/storms in our area. Some severe weather and heavy rain
potential does exist if we see organized storms tonight, given
the remains of an elevated mixed layer providing for decent
instability aloft in the region to go along with about 30 knots
of deep-layer bulk shear overnight. Given that instability will
be building from the southwest tonight, the greatest severe
weather concern would likely be towards northwestern and central
Ohio.
The warm front and overnight activity are expected to exit to
the east into Sunday morning, leaving a general lull to start
the day. As a shortwave moves into the Great Lakes Sunday
afternoon into Sunday night, it will push a cold front south
into our area while large scale ascent also improves. This will
lead to another round of showers and thunderstorms later Sunday
into Sunday night, exiting to the southeast into early Monday.
Scattered showers/storms may begin developing early to mid-
afternoon, but expect the most widespread activity to occur
after 4 PM from northwest to southeast as the front sinks in and
as large scale ascent ahead of the shortwave overspreads the
area. The greatest severe potential will likely be late-
afternoon through mid- evening on the balance.
Am fairly confident that we`ll have enough heating of a very
humid airmass to yield moderate to strong instability Sunday
afternoon and evening, with at least 1500-2500 J/KG of MLCAPE
expected, potentially a bit more if we heat up enough. With
sufficient heating, well-mixed low-levels beneath a punch of
mid-level dry air ahead of the cold front would aid convective
downdraft potential, with moderate DCAPE of near 1000 J/KG
possible. Mid-level lapse rates will be somewhat marginal as the
elevated mixed layer gets worked over by the repeated rounds of
convection in the region. Deep-layer shear is modest until late
in the day Sunday, but increases to 30-40 knots into the
evening. Flow is fairly unidirectional limiting helicity, but in
the evening the low-level jet ramps up a bit which may yield
100-150 m2/s2 of effective helicity. This all adds up to
conditions favorable for strong to damaging wind gusts with any
stronger/more organized storms. With shear vectors parallel to
the front and increasing ascent, expect activity to become
linear pretty quickly, which will largely favor the wind
potential and keep any larger hail or weak tornado potential on
the lower side overall (though, just enough shear to give a
marginal hail/tornado potential despite a largely linear mode).
The SPC has a Slight Risk for severe weather (risk level 2/5)
for our entire area for Sunday afternoon/evening, which is
agreeable. Some hi-res guidance shows widespread activity
developing too quickly Sunday afternoon to take advantage of the
better forcing and shear in the evening, which does give a
possible fail mode, as that kind of evolution would limit the
severe threat overall. Conditions become favorable for training
and back- building convection with heavy rainfall into Sunday
night. Flash flooding is a concern, especially if we see
activity largely hold off until later when shear/forcing are
more favorable, and especially if we see locally heavy rain
tonight to prime the area for flooding concerns with tomorrow`s
round. No flood watch or anything at this time due to the
uncertainty.
It will be very humid behind the warm front tonight into Sunday,
with dew points climbing to near 70. Highs may near or exceed
90 on Sunday assuming we see some sunshine from the morning into
at least the early afternoon, which would push heat index
values into the mid- upper 90s. Dew points and temperatures
don`t really drop off until very late Sunday night behind the
front.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A rather healthy cold front will finish tracking across our region
before sunrise Monday morning. There may be a few lingering showers
across our far southeastern areas first thing Monday morning. A high
pressure system coming down from south central Canada into the Upper
Midwest region will start building into the Great Lakes and Upper
Ohio Valley region on Monday. We will have some very nice weather
and comfortable temperatures to start out next week. Overall
afternoon high temperatures will be in the middle 70s to lower 80s.
More noticeably, the airmass will be less humid with dewpoints
falling into the 50s. Overnight temperatures will also drop down
into the upper 50s away from the lakeshore and urban areas.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
The next weather system to watch will be associated with a stronger
upper level trough digging down across the Upper Midwest and Great
Lakes region for the middle and end of next week. A warm front will
lift northeastward across the area early on Wednesday. We may have a
chance for a few scattered showers and storms along this warm front.
A slowing move cold front will start to enter the lower and eastern
Great Lakes region later on Wednesday. Initially the mid level flow
will be zonal with the parallel cold front. This mid level flow
will briefly stall it out Wednesday evening into Thursday. The upper
level trough will sharpen up late Thursday into Thursday night and
will also be the driving force to push the cold front through our
region by Thursday evening/night. We will continue to have the
potential for several rounds of scattered showers and storms before
that cold frontal passage. It is too to say if we will have the
threat for organized severe weather but it could be possible given
the strength of that upper level trough later on Thursday. There may
also be a heavy rainfall there if we do have several rounds of
storms. High pressure and wonderful weather conditions will move in
by next weekend with temperatures in the 70s and sunny skies.
&&
.AVIATION /00Z Sunday THROUGH Thursday/...
The forecast area is dry and VFR with a few mid-to-high clouds
across the region. A warm front will lift north into the area
overnight while convection presently over eastern Wisconsin will
track southeast into the airspace. Have ceilings coming back
into the terminals with then a window for TS overnight. The best
terminals for non-VFR and TS are KTOL and KCLE and have some
fairly aggressive tempo groups for wind and MVFR. This first
round of convection should wane by daybreak and allow for a
quiet and VFR late morning and early afternoon. Another round of
convection is expected Sunday afternoon and evening and have
begun those mentions in some TAFs. Winds will be generally south
to southwest through the period with gusts over 20 kts Sunday
afternoon.
Outlook...Brief non-VFR possible in any thunderstorms late
Sunday night through Monday morning. More non-VFR possible in
showers and thunderstorms on Wednesday and Thursday.
&&
.MARINE...
A warm front will lift northeastward across the lake this evening or
overnight. Winds will become 10 to 15 knots from the south-southwest
late tonight and Sunday. A cold front will move across the lake
Sunday evening. High pressure will bring Northwest winds 8 to 15
knots late Sunday night through Monday night then becoming westerly
and lighter by Tuesday 5 to 10 knots. Southerly to southwesterly 5 -
10 winds return by the middle of next week. No headlines are
expected at this time for the lake through early next week.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.
&&
$$
SYNOPSIS...Sullivan
NEAR TERM...Sefcovic/Sullivan
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Sefcovic
MARINE...Griffin
Area Forecast Discussion
National Weather Service Cheyenne WY
525 PM MDT Sat Jul 23 2022
.SHORT TERM...(This evening through Monday)
Issued at 224 PM MDT Sat Jul 23 2022
Already an active day across the CWA. Showers started early this
morning with storms entering Carbon County around 7 AM. These storm
trekked east, producing a few lightning strikes as well as 40 mph
gusts. The cold front that was expected today also moved south
across the CWA this morning, reaching the Colorado border by
about 10 AM. The frontal passage also had some brief gusty winds
behind it, with gusts up to 40 mph. The passage of the front this
morning, as well as some extra cloud cover has kept temperatures
in the 70s and 80s for most places this afternoon. Shower and
thunderstorm activity will continue through the rest of the
afternoon and through the evening. Severe potential looks limited,
however, gusty winds up to 55 mph are possible since model
soundings show a classic inverted- V for this afternoon. PWATs are
also elevated at ~1 inch so heavy rain with storms is also a
concern. Following HRRR guidance, most of the storm activity
should be done by about 8 or 9 PM tonight.
A better set-up is expected on Sunday which will lead to another
active weather day. A good surge of moisture out of the southwest
will keep PWATs elevated across the CWA. Model soundings across the
area also show a good deal a moisture within their profiles.
Soundings show more instability as well, with the potential for CAPE
values to exceed 1000 J/kg by mid afternoon. Strong to marginally
severe storms look possible as the CWA sits in the right entrance
region of a 250 mb jet. Biggest concern with these storms would be
heavy rains due to elevated PWATs. This could lead to ponding of
water on roadways and in urban areas. Gusty winds up to 60 mph and
small hail are also possible with these storms. As far as timing of
these storms, Hi-Res models show some precip entering the southwest
corner of the CWA and high terrain by late morning. Storms will
likely become more numerous and push to the east as the afternoon
progresses. Most storms should be out of the area by midnight.
Because heavy rain is one of the main concerns tomorrow, burn scar
flooding could become an issue.
Monday looks quieter due to an intrusion of dry air across the area.
The better moisture gets pushed further off to the east, and as a
result, PWATs do decrease. A shortwave passing to the northeast may
trigger some thunderstorm development during the afternoon, but
overall, mostly sunny skies will dominate.
.LONG TERM...(Tuesday through Saturday)
Issued at 224 PM MDT Sat Jul 23 2022
Key Impact Messages:
1) Above normal chances of rainfall continue to be probable
Wednesday through Friday and perhaps Saturday for at least central
to southern portions of the region.
2) Near average to cooler then normal temperatures also probable
under the NW flow regime and additional daytime cloud cover.
Weather Discussion: Multi-model consensus and time-lagged
deterministic plus ensemble support continues to highlight a
shifting H7-H3 ridge over the western CONUS and opening the door for
troughing across the northern Plains for much of the long term
period. Wyoming and West Nebraska will be bifurcated by these two
systems with the ridge allowing for greater monsoonal-based PWATs to
shift farther north by Wednesday along with additional moisture also
pivoting in from the NW and then backing up against the Laramie
Range. Tuesday will be the transition day with drier air west of the
Laramie Range and upslope east flow across the WY/NE High Plains.
Elevated fire weather conditions could occur across Carbon County
with scattered showers and storms on the High Plains Tuesday under
H5 NW flow with a large trough over the north-central Plains.
This pattern looks to remain in place through at least Friday with
migratory vorticity impulses crossing Wyoming and Nebraska and
aiding at least diurnal scattered showers and storms. Better
precipitation signal across ensemble means and time lagged
deterministic models highlight central and south portions of the
region and into Colorado through the end of the week and perhaps
into next week as well. PWATs will remain anomalously elevated at +1
to 2 standard deviations with overall instability and shear on the
weak to modest side. There could be a few windows for briefly strong
to severe storms but main hazard currently appears to be pockets of
moderate to heavy rainfall, frequent lightning, and erratic`gusty
winds of 30-50 mph. However, if greater instability is realized with
0-6km shear profiles of 30-40kts, strong to severe storms can`t be
fully ruled out mid to late week. With the added moisture, clouds
and slightly cooler H7 temperatures will be in place resulting in
70s/80s with a slow warm up end of the week. Lows will still remain
near average with clouds reducing radiation cooling opportunities.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 521 PM MDT Sat Jul 23 2022
Wyoming TAFS...VFR, with occasional MVFR in thunderstorms until
02Z producing wind gusts to 35 knots. Wind gusts to 23 knots at
Laramie after 12Z, and to 25 knots at Rawlins after 18Z Sunday.
Nebraska TAFS...VFR. Showers in the vicinity at Sidney until 03Z.
Wind gusts to 26 knots at all terminals until 04Z, and to 24 knots
at Scottsbluff after 18Z Sunday.
&&
.FIRE WEATHER...
Issued at 224 PM MDT Sat Jul 23 2022
Minimal fire weather concerns expected on Sunday due to widespread
wetting rain and thunderstorm chances. Elevated fire weather
conditions are possible on Monday, especially for areas west of the
Laramie Range. Humidities here fall into the low teens with wind
gusts up to 30 mph. Scattered afternoon thunderstorms are possible
Tuesday, which could contain gusty, erratic winds.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...SF
LONG TERM...JSA
AVIATION...RUBIN
FIRE WEATHER...SF
Area Forecast Discussion
National Weather Service Duluth MN
628 PM CDT Sat Jul 23 2022
.DISCUSSION...(This evening through Friday)
Issued at 334 PM CDT Sat Jul 23 2022
Summary: Chances of showers and thunderstorms linger across the
Northland this afternoon and evening before tapering off tonight.
Drier conditions are expected for Sunday, although some isolated to
scattered light rain showers will be possible. Another chance of
showers and thunderstorms is in place for Tuesday through Thursday.
Temperatures this week will be near to below seasonal for this time
of the year.
We continue to monitor two areas of light to moderate rain showers
ongoing for portions of the Northland: 1) across the Borderland
ahead of a mid-level shortwave impulse that will continue to
translate from west to east, and 2) across our southern areas due to
an elevated warm front that has lifted northward. Confidence in any
strong to severe storms has decreased for this forecast package due
to the ongoing shower activity helping to tamper down the
instability. The highest instability remains over northwest
Wisconsin, closer to the surface warm front, with surface-based CAPE
values hovering around 1000-2000 J/kg per the RAP analysis. However,
this area is currently being worked-over by the ongoing shower
activity, so this instability should be eaten into throughout the
afternoon hours. At this point, we are watching an area of clearing
skies around Grand Rapids, MN and points west, where temperatures
have warmed to the upper 70s to lower 80s. This area is ahead of a
cold front that will make its way southeastward this afternoon and
evening, which could spark off some stronger convection along it.
However, this environment ahead of the cold front appears unlikely
to support severe convection either due to unfavorable mid-level
lapse rates. Still, there remains a Marginal Risk of severe storms
across a majority of the Northland from SPC, with the Slight Risk
pulled completely out of northwest Wisconsin.
Eventually, the cold front will exit the Northland this evening and
overnight, leading to the remaining chances of showers and storms to
dissipate. There will be a brief lull in precipitation chances
tonight before a compact mid-level shortwave dives southward Sunday.
While forcing for ascent will increase, along with decent height
falls, minimal instability will be in place, so we are expecting
only some isolated to scattered rain showers and isolated
thunderstorms. The next chances for showers and storms return on
Tuesday, lingering through the day Thursday. The main reason for
this prolonged period of precipitation is an upper-level cut-off low
pressure system that will develop over the Canadian Prairies and
lingering over western Ontario Canada. A few mid-level shortwave
impulses will rotate around the upper-level low, supporting these
chances of showers and thunderstorms. The environment doesn`t appear
to be conducive to strong to severe convection during this time
frame, with modest instability and shear progged by the global
models. Eventually, things do appear to dry out late next week.
For the upcoming week, high temperatures will warm to around the
lower to middle 70s for most locations, which is around or slightly
below seasonal average.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 622 PM CDT Sat Jul 23 2022
Some cells producing lightning and small hail are dotted across
the area, but for the most part the thunderstorm activity should
be coming to an end in the next few hours. VCTS are left in the
TAFs for all terminals to account for leftover activity into this
evening. High moisture aloft overnight from today`s rain could
lead to lowered MVFR ceilings tonight, and fog is possible at HYR.
All terminals are expected to remain MVFR or above, but could dip
down to IFR from passing thunderstorms or early morning fog (HYR).
Conditions should return to VFR by mid morning Sunday.
&&
.MARINE...
Issued at 334 PM CDT Sat Jul 23 2022
East to northeast winds around 5 to 10 knots will remain in place
through the afternoon and into the early evening hours today before
becoming light and variable tonight. The main concern for late this
afternoon through the evening hours will be increasing chances of
thunderstorms along an approaching cold front. There is a low
possibility that one or two of these storms become strong to severe,
but if they do, they will be capable of large hail and strong, gusty
winds, which could result in locally higher waves as well. Sunday
will be a quieter day, with only a low chance for a shower or
thunderstorm during the afternoon hours. Winds will turn more
westerly, generally around 5 to 15 knots. Gusts to around 20 knots
will be possible along the North Shore, which doesn`t quite hit
Small Craft Advisory criteria, but is just shy of this threshold. If
the models trend upward for the wind gusts, then advisories may need
to be considered.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 58 72 51 76 / 40 20 0 0
INL 55 67 48 74 / 30 20 0 0
BRD 58 72 50 77 / 20 10 0 0
HYR 58 74 47 77 / 40 20 0 0
ASX 59 75 53 78 / 40 20 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&
$$
DISCUSSION...JTS
AVIATION...Kossen
MARINE...JTS
Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1029 PM EDT Sat Jul 23 2022
.UPDATE...
A linear MCS has pushed onshore across western Lower Michigan with
apex of bow echo near Muskegon and Grand Haven. Most notable aspect
of the system was the development of a coherent rear inflow jet
feature that included some 80 knot velocities at roughly 5000 ft agl
over central Lake Michigan. Should be getting a good handle on what
the surface wind gust potential is as the orthogonal line segement
at the apex is traveling right down the radial into the KGRR 88d.
Latest hires nwp has continued to support the 12Z HREF data that
shows a significant weakening of the reflectivity depth (modeled)
and composite intensity (modeled) once the MCS enters Lower Michigan.
KDTX 00Z sounding shows a stable prestorm environment with plenty of
CIN that will need to be overcome particularly with the subsidence
inversion between 8.0-13.0 kft agl. The structure of the midlevel
inversion suggests the subsidence was active at observation time
which was supported by the lack of cloud this afternoon. The
approach of the forward propagating outflow supports a line feature
coasting into portions of the cwa between the 03-05Z timeframe. The
current trajectory suggests the I 96 corridor stands the best chance
to see strong to potentially severe wind gusts this evening. No
widespread severe weather is anticipated.
Zonal jet axis overspreading the area will support continued moisture
transport throughout the night. NWP supports additional shower and
thunderstorm activity pushing into the region, particularly north
after 09Z on the nose of a strengthening low level jet. Model
soundings depict near surface stability building through 5000 ft agl
during the early morning hours so thunderstorm activity is expected
to remain elevated. Decent enough EML with steep 800-600mb lapse
rates keeps MUCAPES at 1500 J/kg or so. No organized severe weather
is anticipated because of the stable layer, but training may lead to
heavy rainfall for some locations.
&&
.PREV DISCUSSION...
Issued at 753 PM EDT Sat Jul 23 2022
AVIATION...
Timing and location of multiple rounds of thunderstorm activity is
the main focus of the aviation forecast. Did not make any
significant changes to the going tafs which has called for a line of
thunderstorms and/or old forward propagating gust front through the
Detroit terminals between 04-07Z. Would like to get a look at the
00Z data before shifting any expectations. That being said...latest
regional Z mosaic and satellite trends support a northward shift
with the MCS that is currently tracking through eastern Wisconsin.
At the present time, an extrapolation of high cloud tops/tallest
reflectivity cores brings the bulk of the MCS through the northern
cwa. There can still be a gust front/outflow that setups along the
southern flank of the convection and will maintain the DTW/YIP/DET
TSRA out of deference for that potential. Arguably, the greatest
synoptic support exists across the northern cwa tonight with better
proximity to the cyclonic shear side of inbound jet and the modest
dcva that occurs with the system this evening. Things become messy
then the latter half of the night/early Sunday once the zonal jet
spreads across the region with fast and continuous
moisture/instability transport in addition to cloud top cooling
considerations. Stayed with the inherited timing between 14-18Z. The
last time period of potential for thunderstorm development will be
late Sunday afternoon between 21-00Z as the cold front finally drags
southward through Southeast Michigan.
For DTW...Still expecting thunderstorm activity accompanying an
outflow through DTW between 04-07Z tonight. Will be monitoring
trends this evening and will amend as needed. The potential for
showers and thunderstorms remains during the mid to late morning
hours Sunday but considerable uncertainty exists with regards to
coverage/location/timing of showers and thunderstorms. The potential
also exists for thunderstorms late Sunday afternoon.
DTW THRESHOLD PROBABILITIES...
* Medium for thunderstorms in the 04-07z time window tonight. Medium
for thunderstorms Sunday morning and afternoon.
* Low for ceilings aob 5000 feet through Sunday.
PREV DISCUSSION...
Issued at 437 PM EDT Sat Jul 23 2022
DISCUSSION...
Observations up to press time indicate subsidence in the wake of the
morning MCS holding Ok across SE MI as cirrus debris clears to the
east this afternoon. The northern Lower MI higher terrain has
activated with a few thunderstorms worthy of a chance POP in the
Thumb and then down toward Lake St Clair where some cumulus outline
additional low end potential. High temperatures there make a run
toward 90 with a pocket of Td in the mid 60s perhaps able to add
some late day instability near the shoreline. There are several more
hours of peak heating for stray convection to materialize, however
the earlier mesohigh/wake trough has mostly filled into a weak and
featureless surface high across the rest of Lower MI.
The remaining late day surface heating will serve more to set up
instability downstream of the MN/IA/WI MCS and provide a corridor
for it to migrate into southern Lower MI later tonight. As it stands
at press time, the system shows a number of strengths that add
confidence to maintenance. IR satellite imagery indicates a
convincing area of cold cloud tops along with very high lightning
flash rate which suggests the somewhat still discrete character of
the convection will continue to grow upscale during the late
afternoon and evening. Hourly mesoanalysis and near term forecasts
show the instability gradient moving slightly farther north from the
southern WI/northern IL corridor while RAP estimates a plume of near
EML 8C/km 700-500mb lapse rate over the south half of Lake MI. This
adds confidence to MCS maintenance mainly south of the I-69 corridor
and and possibly a couple hours earlier than the latest HRRR timing
into the Ohio border region of SE MI roughly in the 10 PM to 2 AM
time range. The system is expected to be fully mature and capable of
severe wind gusts as the primary hazard with higher probability
along the I96/696/94 corridor while also possibly trending down from
peak intensity after midnight. There is a downstream instability
reservoir but more along the line of MLCAPE in the 1000-1500 J/kg
range in a veered wind profile compared to 3000+ J/kg with better
inflow over the Midwest genesis region.
The second phase of this active weekend of convection gets underway
over the upper Midwest again later tonight. The low level jet is
projected to ramp up to around 40kts at 850mb activate another round
of nocturnal convection across MN/IA/WI/IL which then migrates along
the elevated warm front mainly into central Lower MI as 850mb wind
ramps up to around 40 knots. This activity will be more elevated for
SE MI to present a heavy rain threat along with possibly some hail
in any stronger updrafts. A swath of rainfall totals in the 1-2 inch
range is solidly possible across the Tri Cities and northern Thumb
but likely staying north of Flint and the I-69 corridor through
Sunday morning.
The final stage of this system brings the cold front into Lower MI
Sunday afternoon. All of the moving parts described above will have
a say in how things turn out for storms along the front but none
more than the scope of coverage and duration of the late night and
morning activity. The nocturnal convection is expected to have a
northward focus but with still enough coverage in the south for an
impact on renewed destabilization in the afternoon. The assumption
at this point is mid to late afternoon recovery will be adequate for
late day initiation in SE MI before the front exits eastward. The
initial discrete convective cells will have a strong wind field with
model soundings offering bulk shear in the 40-50kt range in a mostly
unidirectional hodograph. The big question is if CAPE will recover
back toward ML values high enough for organized convection, or a
target around 1500 J/kg, which will be a close call before the front
exits into Ontario by Sunday evening.
Passage of the cold front brings in cooler and less humid conditions
for the early week period. Dry weather is expected until possibly
another round of showers late Tuesday night into Wednesday.
MARINE...
A warm front and an approaching low pressure system will bring
increasingly unsettled conditions tonight into Sunday. Moderate
south to southwest wind and dry conditions prevail most of the
afternoon and evening with just a slight chance of a shower or
storm. Confidence is increasing on a more potent thunderstorm
complex to track from the Midwest across the central Great Lakes
late tonight. These storms may be strong to severe with strong wind
gusts, torrential downpours, and hail all possible tonight into
early Sunday. Strong southwest winds aloft will precede the passage
of a cold front during the day Sunday, lending moderate confidence
in a period of 25+ kt gusts across the nearshore waters. A Small
Craft Advisory has been issued for tomorrow as a result. Wind shifts
to the northwest tomorrow night in the wake of the front with high
pressure then expanding into the region on Monday.
HYDROLOGY...
Locally heavy rainfall remains possible across all of SE MI as
several rounds of thunderstorms move through the region. The latest
data show a swath of higher rainfall likely across the Tri Cities
and Thumb where totals around 1 inch are likely with 2 inch totals
possible tonight and Sunday morning. Totals of 1 inch or less are
expected for locations along and south of I-69 through metro Detroit
with a few locally higher amounts possible late this evening and
overnight when an organized storm system is expected to track
through the region. Another round of storms is possible Sunday
afternoon before a cold front sweeps activity eastward Sunday
evening. Flooding of prone urban locations and other low lying areas
is the main threat followed by moderate rises in smaller creeks and
streams around the region.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
Lake Huron...Small Craft Advisory from 8 AM to 4 PM EDT Sunday for LHZ421-422-
441>443.
Lake St Clair...Small Craft Advisory from noon to 10 PM EDT Sunday for LCZ460.
Michigan waters of Lake Erie...Small Craft Advisory from noon to 10 PM EDT Sunday for LEZ444.
&&
$$
UPDATE.......CB
AVIATION.....CB
DISCUSSION...BT
MARINE.......TF
HYDROLOGY....BT
You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.
AREA FORECAST DISCUSSION
National Weather Service Sioux Falls SD
1045 PM CDT Sat Jul 23 2022
.SHORT TERM...(This Evening through Sunday)
Issued at 335 PM CDT Sat Jul 23 2022
Current surface analysis indicates an area of low pressure over our
south central SD counties, with a warm front extending eastward
along the central and eastern Interstate 90 corridor. This low will
slowly drop to the southeast through the afternoon, as a cold front
slides southward across the area. There has been a good deal of
cloud cover across the area through the day, which has inhibited
heating somewhat, but current satellite is showing clouds beginning
to break. The question becomes whether additional stronger storms
will develop by this evening with additional heating through the
afternoon. Most recent hi-res model runs - most notably the HRRR and
NAM Nest are indicating stronger convection developing along the
front through northwest IA around 00Z, then tracking to the south
and east before exiting our area by 04Z. RAP bufkit soundings
indicate MUCAPE values of 2500-3000 J/kg in place this evening,
along with effective bulk shear running around 50kts. This with
midlevel lapse rates of 7 to 8 C/km, and an increasing midlevel flow
will bring the potential for severe storms to occur. The main
threat with these storms would be hail to the size of golf balls and
winds to 70 mph. After the storms exit, cooler and drier air will
begin to filter into the region with lows tonight in the upper 50s to
mid 60s.
As a side note, because of the cloud cover through the day,
temperatures did not warm as quickly as was previously forecasted,
so went ahead and cancelled the Heat Advisory for our southern
zones. While there will be a possibility of a few locales nearing
criteria late, it would be for a duration of only and hour or two.
Sunday looks to be a nice day as surface high pressure builds into
the region. With continuing cold air advection behind the front,
highs will run upper 70s to mid 80s. It will also be less humid as
dewpoints fall into the 50s.
.LONG TERM...(Sunday Night through Saturday)
Issued at 335 PM CDT Sat Jul 23 2022
For Sunday night, a shortwave begins to drift out of the Central
Rockies, with midlevel warm air advection overspreading our area.
With that there could be isolated showers through the central MO
River corridor late. The better forcing looks to be to our south and
west however, and with the lack of any deeper moisture over our area
not expecting much rainfall. It will be seasonably cool on Sunday
night with lows in the upper 50s to lower 60s.
A more significant shortwave slides across the region on Monday,
followed by another one on Tuesday. This will keep rain chances
across the area through the period, though rainfall amounts look to
be on the light side at less than half an inch through the entire
period. Highs both days will be close to normal - in the lower to
mid 80s.
Upper level energy over central Canada deepens and drops southward
by the middle and end of next week, with a broad trough setting up
over the Upper Mississippi Valley through the Great Lakes region.
This puts our area in a northwesterly upper level flow, with
temperatures at or just below normal for Wednesday through Friday.
Rainfall chances look low through the period, with ECMWF and GEFS
ensembles indicating a less than 10 percent chance of rainfall
greater than half an inch during the period.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1044 PM CDT Sat Jul 23 2022
Showers and thunderstorms have exited the area off to our east,
ending the concern for severe weather. However with the recent
rainfall, light winds and clearing skies will lead to chances for
fog formation primarily across portions of NW Iowa, possibly
impacting the SUX terminal during the late overnight into morning
hours. Morning winds pick up slightly
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JM
LONG TERM...JM
AVIATION...APT
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
636 PM CDT Sat Jul 23 2022
.UPDATE...
Issued at 542 PM CDT Sat Jul 23 2022
Updated the forecast this evening to hone in on the line of storms
moving east across the CWA as we get a better idea of coverage and
timing. Leaned even more with latest runs of HRRR and tightened up
the gradients with this line. Severe parameters suggest that after
10 PM, the chance for severe weather declines significantly. The
primary threat will become mostly severe wind gusts, but
marginally severe hail will also be possible.
&&
.DISCUSSION...(This evening through Saturday)
Issued at 224 PM CDT Sat Jul 23 2022
The main story for this forecast is the threat for severe
thunderstorms late this afternoon and this evening. A cold front
is currently pushing across the Sandhills, stretching from near
Imperial to North Platte to O`Neill as of 2pm. This will continue
into the local forecast area late this afternoon. There has been
relatively limited cumulus development in its vicinity so far due
to fairly strong capping aloft, but there is good agreement in
models that the frontal forcing will result in fairly rapid
development by 4-5pm at the latest. These storms will then
generally push eastward through the evening hours.
The hot, moist airmass ahead of the front, along with increasing
deep layer shear will result in ample instability for intense
sustained updrafts. This may result in isolated large hail, but
the main threat appears to be from downburst winds with high cloud
bases resulting in large DCAPE values. Additionally, an isolated
landspout tornado or two cannot be ruled out as well. Parameters
are not favorable for classic supercellular tornadoes, but
combination of favorable low-level lapse rates and strong sfc
vorticity along the front leads to a heightened landspout threat,
especially for southwest parts of the area.
Slight chances for showers and thunderstorms linger into Sunday
morning. Behind the cold front, Sunday will be significantly
cooler, and highs are only expected to reach the 80s. Chances for
showers and storms then increase again Sunday night as a shortwave
arrives from the southwest, bringing in fairly deep moisture.
Instability is fairly limited, though, so severe weather is
unlikely. Rain amounts will not be overly heavy, but the totals do
favor the southern half of the area. This would be a welcome
sight to portions of KS that have been pretty dry as of late.
The pattern remains on the cooler side through the week as an
upper low pushes southeastward out of Canada and into the upper
midwest. We will also have daily chances for rain and storms. At
this point, it appears the the highest chance for rain (and
perhaps some severe storms) will be Tuesday night. As expected,
convective details are murky, at best, through the upcoming week,
but convective parameters do not look particularly concerning for
any of the days.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Monday)
Issued at 633 PM CDT Sat Jul 23 2022
Main issue for this forecast will be in the first few hours as
thunderstorms move east along a cold front. This broken line of
storms should be east of both terminals by 03Z with winds
ultimately turning to the northwest. Wind should become northeast
to east well behind the front for Sunday.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...Heat Advisory until 8 PM CDT this evening for NEZ039>041-046>049-
060>064-072>077-082>087.
KS...Heat Advisory until 8 PM CDT this evening for KSZ005>007-017>019.
&&
$$
UPDATE...Heinlein
DISCUSSION...Mangels
AVIATION...Heinlein
Area Forecast Discussion
National Weather Service Indianapolis IN
1048 PM EDT Sat Jul 23 2022
...Updated Aviation Discussion...
.Forecast Update...
Issued at 954 PM EDT Sat Jul 23 2022
A few adjustments required to the forecast this evening. No
convective activity is in the vicinity at this time and appears
unlikely to be at least until late tonight. Complex over southern
Lake Michigan into southeast Wisconsin should weaken as it makes
slow southeastern progress, but the tail end of the complex or
showers along the boundary to the west may make it into the far
northwestern portions of the area just before daybreak, thus have
increased early day pops slightly in that area.
Temperatures are running a bit cooler than forecast and dewpoints
are well below expected values at this time, thus have lowered min
temps at least a couple degrees across the board.
&&
.Short Term...(This evening through Sunday night)
Issued at 303 PM EDT Sat Jul 23 2022
- Rain ending this afternoon and evening north
- Chances for more showers and thunderstorms Sunday
Surface analysis early this afternoon shows strong high pressure in
place over the southeastern states. This was resulting in a warm and
humid southerly flow of air into Central Indiana. A boundary left
from earlier and ongoing convection was front across northern
Illinois, Northern Indiana and stretched southeast into Western
Ohio. This boundary continues to be the focus for convection early
this afternoon. Outflow from the ongoing convection has led to NE
winds across Central Indiana. However as convection wanes, southerly
surface flow is expected to resume.
Tonight...
Models show the weak short wave that has been aiding convective
development today exiting to Ohio this evening. Furthermore, the
lingering boundary that has been a focus for convection is expected
to drift east, remaining mainly north of Central Indiana this
evening. HRRR continues to indicate convection waning this afternoon
as the upper shortwave departs. Thus may need to keep some low
chances late this afternoon across the far north, but overall will
be leaning toward a dry forecast.
For the rest of the evening and overnight, models show NW flow
remaining in place aloft with little in the way of forcing available
aloft. The next shortwave appears to be found over the mid-
Mississippi Valley, poised for a Sunday arrival. Forecast soundings
and Time heights show a dry column. Thus will trend to a dry, warm
and humid night as southerly flow is expected to return. Will trend
lows to the low to mid 70s.
Sunday...
Models continue to suggest little change within the lower level flow
as southerly flow looks to remain dominant due to strong high
pressure to the southeast. Models do show the arrival of a cold
front over the Central Plains, becoming elongated and slowly pushing
east across Central Indiana through the day. Aloft, some forcing
appears to be in place accompanying the cold front. Forecast
soundings on Sunday show a favorable column for convection ahead of
the front with ample CAPE over 2500 J/KG, attainable convective
temperatures in the lower 90s and high pwats over 2 inches.
Furthermore SPC HREF updrafts show plentiful updrafts across central
Indiana during the afternoon. Thus after a dry morning, will trend
toward high chance pops on Sunday afternoon as these favorable
ingredients for precip come into play. With ample heating and time
in the warm sector on Sunday morning and early afternoon, highs in
the lower 90s appear quite reasonable.
Sunday Night...
The previously mentioned cold front and associated dynamics are
shown to drift south to the Ohio River On Sunday Night. This will
allow a cooler and drier NW surface flow to build across Indiana.
Forecast soundings show subsidence arriving overnight as the
forecast column dries out. High pressure over the upper midwest is
then expected to build southeast into the Ohio Valley overnight as
the earlier trough axis pushes far east and subsidence builds across
the area. Thus will trend overall toward a decreasing cloudiness
type forecast. We may need to include some pops across the far south
during the evening for possible departing showers/storms shortly
after 00Z, but overall the trend will be toward a dry forecast
overnight.
&&
.Long Term...(Monday through Saturday)
Issued at 303 PM EDT Sat Jul 23 2022
Upper flow over the Great Lakes and Ohio Valley regions will largely
be quasi-zonal which will be supportive of an unsettled pattern
through much of the week. Expect relatively cooler temperatures with
highs in the 80s and daily precipitation chances due to multiple
short waves moving through for next week.
The work week will start out with a surface boundary slowly shifting
southward during the day Monday before stalling near the Ohio River
due to a persistent high to the south. At this time, rain and storm
chances are expected to decrease through the day but the boundary
looks to push back north Tuesday, returning the chances for
precipitation.
The main system will come mid week as a more potent wave off of a
low over central Canada brings a frontal boundary through the
region. Ahead of this front, SW flow at the surface will set up and
bring the warmest day for the week on Wednesday with highs in the
mid to upper 80s. The best chances for showers and thunderstorms in
the long term will come with this system, so keeping with the likely
PoPs. Could also see non-thunderstorm gusty winds on Wednesday along
the front. Models seem to agree that this boundary will become
sluggish and stall over the region towards the end of the week. This
will prompt a mention of PoPs until the end of the long term. Behind
the frontal boundary, a surface high will allow for a more stable
atmosphere and an end to the rain, but a lack of clear upper
steering will bring uncertainty as to when the front will be able to
progress off to the south. It does appear that the upper level
pattern will finally become more of a trough at some point for the
latter half of the week once the stagnant high across the SE U.S.
progresses eastward over the Atlantic finally allowing the frontal
boundary to exit. Behind the front, relatively cooler temperatures
will again return with highs in the low 80s expected for the end of
the period.
&&
.Aviation...(06Z TAF Issuance)
Issued at 1048 PM EDT Sat Jul 23 2022
Impacts:
* Low level wind shear overnight at LAF.
* Gusty southwest winds Sunday.
* Showers or storms possible Sunday.
Discussion:
Expect primarily quiet weather overnight with VFR conditions.
Convection to our northwest appears likely to miss the sites to the
north overnight, with any precipitation holding off until later in
the period as a cold front approaches.
Some enhanced low level flow feeding into the convection to our
north appears likely to produce some low level wind shear at LAF
tonight, with 2kft winds around 40KT. Other sites should be more
borderline and did not merit a mention.
Winds will be gusty during the day on Sunday, up to around 20-24KT
out of the southwest. Overnight tonight, winds will be a bit more
southerly but may be light and variable at times.
Showers and a few storms appear likely late in the period as a cold
front approaches. Will carry showers with a VCTS mention near peak
timing Sunday (earlier at LAF which should be first to experience
threat).
&&
.IND WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
Update...Nield
Short Term...Puma
Long Term...KH
Aviation...Nield
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
717 PM EDT Sat Jul 23 2022
...New UPDATE, AVIATION...
.UPDATE...
Issued at 715 PM EDT Sat Jul 23 2022
Similar to yesterday evening, storms developed and moved towards the
west coast. A few storms produced strong wind gusts and small hail.
The lingering line of showers along the nature coast and the few off
Pinellas County will continue to diminish as they move further
offshore. HRRR is showing the convection being mostly out of the
area by 02Z.
The southeast flow continues tomorrow, however, there will be a
pocket of drier air aloft with lower PW values. With the drier
air, the models are showing less coverage for tomorrow. The
showers that do pop up will most likely develop inland and reach
the west coast in the evening. With drier air aloft, the main
concern with the storms that do develop tomorrow will be strong
wind gusts. No significant change to the forecast with the evening
update
&&
.AVIATION...
(00Z TAFS)
Issued at 715 PM EDT Sat Jul 23 2022
Storm continue to push offshore, leaving VFR conditions
at all sites. Models are hinting at showers and storms a little
later tomorrow. Southern sites and LAL could begin to be impacted
around 21Z, northern sites around 22Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 78 94 79 94 / 40 40 30 60
FMY 76 94 77 94 / 20 30 20 70
GIF 76 95 76 94 / 30 20 10 60
SRQ 75 93 75 92 / 30 30 20 60
BKV 72 93 72 93 / 40 30 30 60
SPG 78 92 79 92 / 40 40 20 50
&&
Sea Breeze Thunderstorm Regime For Saturday: 6
Sea Breeze Thunderstorm Regime For Sunday: 2
For Additional Information On Sea Breeze Regimes go to
https://www.weather.gov/tbw/ThunderstormClimatology
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...None.
Gulf waters...None.
&&
$$
UPDATE/AVIATION...Pearce
Area Forecast Discussion
National Weather Service Las Vegas NV
817 PM PDT Sat Jul 23 2022
.SYNOPSIS...Moisture will continue to spread over the region early
this coming week leading to increasing chances of thunderstorms for
all of Mohave County and much of Lincoln, Clark, and San Bernardino
counties Monday and Tuesday before retreating a bit eastward
beginning Wednesday. The main threats will be heavy rain and
possibly flash flooding.
&&
.UPDATE...A few thunderstorms developed over remote areas of
northeast Mohave County late this afternoon and early this evening.
Two cells east of Mount Trumbull produced heavy rainfall with 1-2
inches estimated by radar. Those estimates are likely high, but the
storms were fairly impressive. Convection has largely dissipated and
only lingering light rain showers may brush the area around Pipe
Spring National Monument and SR 389 through 9 or 10 PM. Satellite
loops clearly show some embedded disturbances aloft over southern
Nevada and northwest Arizona. Cannot rule out some nocturnal showers
or possibly thunderstorms which the latest HRRR and NBM indicate
developing over the eastern half of Lake Mead and up over northeast
Clark/northwest Mohave counties late tonight and early Sunday
morning. The forecast has been updated to account for this. The rest
of the trends detailed in the previous discussion look on track.
&&
.PREV DISCUSSION...
137 PM PDT Sat Jul 23 2022
.SHORT TERM...through Sunday night. Early afternoon satellite loop
showed an area of light rain showers over southern Clark and
northeast San Bernardino counties drifting slowly north. An
impressive gravity wave was also seen propagating northward away
from the showers. Elsewhere, multi-layered clouds covered much of
Mohave County (but were beginning to erode), and scattered cumulus
dotted the skies north and west of the showers. Surface obs showed
temperatures down substantially from 24 hours ago in areas which had
showers and/or thicker clouds for much of the morning, with less
change in sunnier areas. Expecting low-impact showers with possibly
a few thunderstorms through this afternoon, with much bigger
questions for tonight through Sunday night. Thunderstorms were
firing along the Mogollon Rim in Arizona this afternoon, and how
they evolve overnight will drive a lot of what happens Sunday
afternoon. Some high resolution models show storms (or their
remnants) tracking through northern Mohave County and into Lincoln
County overnight, while others depict them as far southwest as Las
Vegas. How these storms modify the airmass, whether and in which
direction they eject outflow boundaries, and how much area is
covered for how long by the debris clouds will play sizable roles in
the mesoscale environment for Sunday. High resolution models have a
large spread in placement of afternoon convection, so confidence is
low in this regard. Many areas along and southeast of I-15 will have
precipitable water around 1.5 inches, so wherever storms develop,
heavy rain and flash flooding will be the main concerns. Several
high resolution models show storms persisting Sunday night in Mohave
County, with some showing southern Nevada and southeast California
as well.
.LONG TERM...Monday through Friday.
Monsoonal moisture will be in place through much of the week as the
main area of high pressure sets up of the Four Corners region and
southerly flow dominates our weather pattern. The chance for
thunderstorms with impacts such as heavy rain, flash flooding,
lightning, and sudden gusty winds will be possible each
day...however exact details on where impacts will set up and to what
level they might be is still lower confidence.
Ensembles show high probabilities for over 1" PWATs across much
Arizona, southern Nevada, and eastern San Bernardino County for at
least the first half of the week. Monday and Tuesday in general
might be the time period for the highest and most widespread
monsoon impacts as this is when moisture will be the highest at
1-1.5" PWAT for a large area. This is also the time period that
things such as EFI, GEFS M-Climate, and ensemble probabilities of
24hr 100-yr QPF return intervals are highlighting as higher
potential for extreme precipitation...especially in Mohave County.
EC/GEFS means also hint at an impressive vorticity lobe coming
around the anticyclonic flow Monday into Tuesday. If this does
develop, this would further increase concerns for higher
thunderstorm activity and monsoon impacts.
After Tuesday, ensembles diverge about how much moisture will
remain in place over the region. There will likely still be decent
moisture available however there is a chance that the highly
anomalous PWATs in the place the beginning of the week retreat
slightly. GEFS shows this occurring Wednesday while the ECMWF
ensemble doesn`t have moisture decrease until Friday. Long range
models also differ on the placement of the area of high pressure
and where the best southerly flow that pushes moisture northward
will set up. There will probably still be a risk for thunderstorm
impacts the second half of the week for at least portions of the
region but low confidence on anything more than that.
Temperatures will run a few degrees below normal at the beginning of
the week when moisture is the highest and then are expected to
rebound back to near normal for the second half of the week.
&&
.AVIATION...For Harry Reid...Gusty south to southwest winds are
expected to develop by late afternoon and persist into the evening.
A few isolated showers will be possible between 2030Z and 0000Z and
gusty outflow winds to 30kts from the direction of the showers are
possible as they pass. Shower activity should end by early evening
and the prevailing gustiness should end around or shortly after
sunset. While light winds are forecast overnight, an isolated
shower causing an increase in winds will be possible, with the best
chances being between 06Z-10Z. Similar prevailing wind conditions
are expected tomorrow, although the chance of gusty shower and
thunderstorm activity will be higher than today.
For the rest of southern Nevada, northwestern Arizona, and
southeastern California...Gusty southeast to southwest winds are
expected at area TAF sites into this evening. Areas of shower and
embedded thunderstorms will also continue through this evening, with
the Vegas area and Colorado River Valley TAF sites being the ones
most likely to be affected, and gusty winds to 30kts from the
direction of the precipitation will be possible as this activity
passes. Otherwise, winds are expected to decrease overnight before
winds similar to today develop on Sunday. Showers and a few
thunderstorms producing gusty winds will also be possible once again
on Sunday.
&&
.SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report
any significant weather or impacts according to standard operating
procedures.
&&
$$
UPDATE...Adair
SHORT TERM...Morgan
LONG TERM...Nickerson
AVIATION...Planz
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