Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/03/21
AREA FORECAST DISCUSSION
National Weather Service Albany NY
955 PM EDT Wed Jun 2 2021
.SYNOPSIS...
A warm and moist pattern will be setting up across the area for
the next several days. Increasing amounts of moisture will
result in a few showers across the area late this afternoon into
this evening, then a good chance of showers and thunderstorms
on Thursday into Thursday evening. Scattered showers and
thunderstorms will be possible again Friday afternoon, then dry,
warm weather is expected over the weekend.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Rain and showers tracking through our region along and north of
I-90. Back edge of the rain is in the central Mohawk Valley
with only isolated to scattered showers well west in central and
western NY that may reach our region well after midnight. Area
soundings show very little instability, so just showers and
any forcing is weak seen in upper air data across the region.
So, once rain exits by midnight, keeping isolated to scattered
showers through the night but again, much less coverage than
this evening. Just some minor adjustments to temperatures, rain
chances and sky cover through the night. Previous AFD has a few
more details and is below...
PREVIOUS DISCUSSION:
Showers are being supported by an axis of isentropic lift and
moisture advection in deep southerly flow east of an approaching
long wave mid-level trough and within the right entrance of an
upper jet over southern Quebec.
Showers will diminish overnight with the best chance persisting
north and west of the Capital District. Increasing amounts of
low-level moisture will lead to areas of low cloud and patchy
fog development toward morning. Lows in the upper 50s to lower
60s.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
Unsettled weather will continue Thursday into Thursday evening
as the region remains downstream of slowly moving upper trough
over the Great Lakes and also within the right entrance region
of an upper jet associated with confluent flow over northern NY
and Quebec downstream from the trough. Models show a good
consensus that the largest coverage of showers Thursday morning
will be north and west of the Capital District, with showers and
thunderstorms developing eastward toward the Hudson Valley and
western New England during the afternoon and into the evening.
Any severe potential associated with these showers and storms
will depend on the amount of heating and destabilization that
occurs during the first half of the day. The models are showing
their usual differences in the amount of CAPE during the
afternoon with the NAM showing values well over 1000 J/kg while
the HRRR / GFS shows much less instability. Even a compromise
with MLCAPE values near 1000 J/kg would result in at least some
severe potential during the late afternoon Thursday as deep
layer shear will be adequate for storm organization with values
near 40 kts. The CAMs are showing some organized structures in
their reflectivity forecasts late Thursday and SPC has expanded
the marginal risk across our entire area with a slight risk over
the Catskills. There will also be the potential for localized
heavy rain with some of these storms as there will be some
training potential in the deep south- southwesterly flow and
pwat values will exceed 1.5 inches.
After a lull in the precipitation chances later Thursday night
and Friday morning, another round of showers and thunderstorms
will be possible Friday afternoon as another short wave moves
southeast across the area and at least modest instability once
again develops. Wind fields / shear look a bit less impressive
on Friday compared to Thursday so storms will likely be less
organized with less severe potential.
After Friday, a quieter pattern develops as upper level ridging
begins to build east from the Ohio Valley. Temperatures will
likely rise above normal by Saturday afternoon with highs in the
80s, setting the stage for a period warmer but dryer weather.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Upper level ridging will continue to build over the region for
the end of the weekend into early next week. 500 hpa heights
rise close to 588 dm by early next week, according to both the
12z GFS and ECMWF. The center of the upper level ridge will
likely be located just southwest of the area over the northern
mid- Atlantic by Monday or Tuesday.
With the high heights and warm temps aloft (850 hpa temps near 18
C), it should be dry with a mostly sunny sky for Sunday and Monday.
Can`t totally rule out a brief high-terrain shower or t-storm on
Tuesday afternoon, but it should be another mainly dry and hot day.
Eventually, a frontal boundary dropping from the north, combined
with an upper level disturbance passing across southern Canada, may
allow for more organized and widespread convection by Wednesday.
Temps will be very warm for the entire extended period and it may
wind up being the first heat wave of the season. Valley areas will
be reaching around 90 on Sunday, with lows 90s for Monday through
Wednesday. Combined with dewpoints well into the 60s, this could
allow heat index values to be close to advisory criteria in some
areas. Even the high terrain will be rather warm, with low to mid
80s in the hills and mountains. Overnight lows will be muggy and
mild, with overnight temps only falling into the mid to upper
60s.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Area of rain and showers with brief reductions in visibility to
MVFR tracking through the region through about 03Z. Ceilings
remaining above 3000 feet during showers and rain. Once this
main area of rain exits this evening, just isolated showers the
rest of the night and into Thursday morning, mainly around
KALB, KGFL and KPSF. Not enough coverage to include KPOU through
Thursday morning. There could be some intervals of MVFR
ceilings at KALB, KGFL and KPSF as low level moisture increases
but mainly at KPSF and KGFL due to inversions more easily
developing in those areas. VFR once again at all TAF sites after
about 12Z.
By Thursday afternoon, showers and isolated thunderstorms
associated with an upper disturbance will develop mainly in the
southern Adirondacks and western Mohawk Valley with more
isolated to scattered activity at KALB, KGFL, KPSF and KPOU.
Including VCSH for the afternoon with PROB30 for showers and
MVFR conditions between 19Z-24Z. Not including thunderstorms
until near term trends show development and timing of
thunderstorms.
Generally south south to southwest winds tonight at less that
10 Kt, with light and variable at times. Winds south to
southwest at 10 Kt or less Thursday morning and afternoon.
Outlook...
Thursday Night: High Operational Impact. Definite SHRA...TSRA.
Friday: Moderate Operational Impact. Chance of SHRA...TSRA.
Friday Night: Low Operational Impact. Slight Chance of SHRA.
Saturday: Low Operational Impact. Slight Chance of SHRA...TSRA.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: Low Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: Low Operational Impact. Slight Chance of SHRA...TSRA.
&&
.FIRE WEATHER...
The chance for showers will increase late this afternoon and
this evening, then there will be good chances for mainly
afternoon showers and thunderstorms Thursday and again on
Friday.
A more humid weather pattern is expected for the next few days.
Relative humidity values will rise to 90-100 percent tonight,
then fall to around 60 to 80 percent on Thursday.
Winds will be light from the south tonight through Thursday with
speeds of 10 kts or less. Thursday night, southwest winds will
once again become light with speeds up to 5 kts.
&&
.HYDROLOGY...
Chances for showers and thunderstorms will then increase from
late this afternoon through Friday as a warm front slowly
approaches from the southwest. Best chance for showers and
thunderstorms looks to be THursday afternoon and evening.
Thunderstorms could produce locally heavy rainfall Thursday and
Friday during the afternoon and evening hours. However,
widespread hydrologic issues are not expected at this time.
For details on specific area rivers and lakes, including observed
and forecast river stages and lake elevations, please visit the
Advanced Hydrologic Prediction Service /AHPS/ graphs on our
website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...MSE
NEAR TERM...MSE/NAS
SHORT TERM...MSE
LONG TERM...Frugis
AVIATION...NAS
FIRE WEATHER...MSE
HYDROLOGY...Evbuoma/Main
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
658 PM CDT Wed Jun 2 2021
.DISCUSSION...Updated for latest aviation discussion below.
&&
.AVIATION...The afternoon conv that was driven by low level
boundaries over the region has moved well north of the RGV leaving
behind VFR conditions. The latest HRRR run indicates that the
conv potential will remain concentrated well west of the region
since the atms over the RGV has been worked over by the conv from
earlier this afternoon and is relatively more stable at this time.
So expect VFR conditons to prevail throughout the short term
period this evening and tonight. Some periods of MVFR ceilings
may be possible after sunset tonight, but the overall confidence
in this is not very high at this time. Then the conv potential
over the RGV airports will start increasing Thurs/Thurs Night as
the 500 mb closed Baja Cali low opens up and starts moving towards
southern TX. As this occurs, expect the probability of MVFR to
occasional IFR conditions to increase due to the better conv chcs.
&&
.PREV DISCUSSION... /issued 245 PM CDT Wed Jun 2 2021/
SHORT TERM (Now through Thursday Night): Continued wet and
slightly cooler temperatures are expected through the short term.
A 500 mb cut off low over Baja California and a 500 mb trough over
the Mississippi Valley will continue to push eastward through the
period. Ahead of this, upper level disturbances will move over
the region over the next few days, keeping the chance of showers
and thunderstorms in the forecast. For the remainder of today, we
could continue see a few showers and thunderstorms across the
area. Some of this activity could produce brief heavy rainfall.
Thursday, showers and thunderstorms chances increase and linger
into Thursday night. With PW values over 2 inches across the
region and saturated soils from previous rainfall, this will
increase the risk for flash flooding in the area and WPC has
placed Deep South Texas in the Marginal Risk for Excessive
Rainfall for Thursday.
Tonight temperatures will fall into the low to mid 70s across the CWA
with increasing cloud cover. Thursday, thanks to cloudy conditions
and rainfall, temperatures will remain just below normal with highs
in the mid to upper 80s, with a few 90s out west. Thursday night,
temperatures will be in the low to mid 70s once again.
LONG TERM (Friday through Wednesday): 500mb low/trough across
west Texas/northern Mexico Friday will continue to provide
unsettled weather across south Texas Friday. Low to mid level
moisture across northeast Mexico into deep south Texas will
continue to provide a threat of heavy rainfall with showers and
thunderstorms Friday. WPC has a marginal threat of excessive
rainfall for the CWA Friday as a result. The upper level low is
progged to move little Saturday and this will continue to provide
a chance of showers and thunderstorms across the Rio Grande Valley
and northern ranchlands Saturday. Rain chances should diminish on
Sunday as the 500mb low moves slowly eastward and subsidence
increases across southwest Texas with a northwest flow aloft. Will
continue to mention a slight chance of showers and thunderstorms
across the area through the rest of the weekend into early next
week as the 500mb low/trough across east Texas Monday will allow
some MCS features to develop across portions of central and south
Texas Monday into Tuesday. There are some differences in the
global models for the rest of the forecast period and the GFS
progs drier air finally moving into the western portions of the
CWA Wednesday while the ECMWF keeps low to mid level moisture high
with a shear axis developing between a 500mb ridge across west
Texas and a 500mb ridge across the southeast United States. Will
continue to mention a slight chance of showers and thunderstorms
through the rest of the forecast period as the NBM continues to
advertise POPs across deep south Texas through Wednesday.
MARINE (Now through Thursday Night): Favorable marine conditions
will prevail through the short term with light to moderate
southeasterly winds and low to moderate seas. However, more
adverse marine conditions are possible with any shower or
thunderstorms that develop on the Gulf waters and Laguna Madre.
Friday through Monday...Light to moderate east to southeast winds
will prevail across the coastal waters Friday with surface high
pressure across the southeast United States extending into the
northern Gulf of Mexico. The pressure gradient should remain weak
across the lower Texas coast Saturday. Light to moderate south to
southeast should prevail across the western Gulf of Mexico
Saturday through Sunday. The pressure gradient is expected to
increase Monday and moderate to strong southeast winds will
prevail across the coastal waters providing SCEC conditions. In
addition...seas will gradually build to SCEC levels for the far
offshore waters Sun night into Monday.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 76 85 74 84 / 20 50 40 50
BROWNSVILLE 76 86 75 86 / 20 50 40 50
HARLINGEN 75 86 74 85 / 20 60 40 50
MCALLEN 75 86 73 85 / 30 60 40 60
RIO GRANDE CITY 74 88 71 87 / 50 60 50 60
SOUTH PADRE ISLAND 78 82 76 80 / 20 50 40 50
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
This product is also available on the web at:
HTTP://WEATHER.GOV/RGV
Short Term/Aviation...60-Speece
Long Term/Upper Air...55-Adams
Area Forecast Discussion
National Weather Service Charleston SC
935 PM EDT Wed Jun 2 2021
.SYNOPSIS...
Abundant moisture and a few disturbances will bring unsettled
weather through late week with some improvement possible early
next week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
As of 930 PM: KCLX indicated a few showers drifting north across
Charleston and Berkeley Counties, another cluster of showers
was centered over Screven and Allendale Counties. Latest run of
the HRRR indicate that rounds of isolated showers will remain
for most of the night. The 0Z CHS sounding observed a low
LCL/LFC, lingering instability, and PW around 1.6 inches. Based
on the observed environment and latest HRRR, I will update the
forecast to spread SCHC PoPs across the CWA and will continue
through the rest of tonight.
Previous Discussion:
This evening: Isolated to scattered showers and a few
thunderstorms will continue near and west of the sea breeze
boundary that merged with the earlier inverted trough. This will
generally impact places near and west of I-95, with a
diminishing trend by sunset. The temperature curve has been
somewhat altered, as we show temperatures in the mid-upper 70s
where the higher rain chances are expected. While isolated
heavy rain amounts will occur, and put down a quick 1/2 to 3/4
inches in less than an hour, the average QPF will be generally
less than 1/4 inch.
Tonight: The upper low between Cuba and the northwest Bahamas
will move south, while an elongated mid and upper level sub-
tropical ridge stretches from the central Atlantic, across
Florida and into the Gulf of Mexico. Where within a southwest
flow aloft in advance of a broad trough that extends from the
Upper Great Lakes to Texas. Meanwhile at the surface, a
humongous ridge that covers most of the Atlantic will cover the
local area. With the loss of heating and diminishing
instability, the majority of convection over land will fade,
while our attention shifts to the coastal waters, where
instability will remain. Scattered showers and isolated
thunderstorms that are initially out near the Gulf Stream will
shift westward overnight. A moisture axis atop the local region
with PWat as high as 1.6 to 1.8 inches will allow for some of
that convection to move onshore during the post-midnight period.
We have 20/30% chances during then, and mainly over the eastern
two-thirds of the forecast zones.
There could be some low stratus that forms late tonight,
especially far inland. But there is likely too much mixing to
allow for any serious fog concern.
Given the elevated dew points within a soutwest to south
synoptic flow, temperatures will struggle to get down to the
upper 60s far inland and just to the lower 70s along the coastal
corridor.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
Thursday: At the surface, high pressure over the Atlantic starts to
loosen its hold over the region by evening as a positively-tilted
upper trough over the Central US lifts northeast. South to southwest
synoptic flow will advect moisture into the area and the presence of
moderate instability will bring scattered showers and thunderstorms
to the region. PWats around 2" will bring measurable precipitation
to the region, with QPF values forecast between 1/4" - 1/2" over the
general area. Locally higher amounts are possible but will likely
not exceed 1 inch. Convection should follow the typical summertime
diurnal inland advancement of the seabreeze, with showers/t-storms
developing offshore/along the coastal regions in the morning,
expanding inland through the evening. Guidance suggests fairly
unimpressive 0-6km shear values between 20-25 kt and MLCAPE topping
out around 1500 J/kg. Mainly pulse-like, short-lived ordinary cells
are expected considering severe parameters are quite benign. Highs
temps are expected be in the 80s, with low 80s near the coast and
mid to upper 80s inland. Lows will generally be in the upper 60s to
low 70s.
Friday and Saturday: Likely much of the same through the period with
the continuation of scattered showers and thunderstorms due to
lingering deep moisture, locally weak troughing, and rippling
shortwaves providing weak upper-level forcing. Temperatures do not
look to fluctuate much, with highs in the mid to upper 80s inland
and lows generally near 70F inland both days. The severe potential
also looks to remain low both days.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Forecast confidence: Moderate with decent model agreement in the
synoptic pattern, although low to moderate regarding rain
chances/amounts/timing. The local area is expected to be sandwiched
between an upper low near TX and one over the western Atlantic much
of the period. This will lead to slightly drier and warmer
conditions with the deepest moisture likely remaining west of the
area. Temperatures should be slightly below to near-normal through
the period.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Moist SSE flow between high pressure over the Atlantic and a
cold front to the west will continue across the terminals
tonight into tomorrow. Guidance indicates that the terminals
will remain dry through late tonight. However, a band of showers
and isolated thunderstorms are expected to increase in coverage
after daybreak Thursday. The TAFs will feature either VCSH or
-SHRA after 13Z. Gusts to around 20 kts are possible at KCHS and
KJZI during the mid to late afternoon.
Extended Aviation Outlook: Periodic restrictions at the terminals
are likely due to low clouds and showers/t-storms, especially
through Saturday.
&&
.MARINE...
Tonight: The sub-tropical ridge will prevail across the maritime
community, which leads to SE and S winds of around 15 kt or less
throughout. Seas will average 2 to 4 feet all waters.
Isolated thunderstorms initially out near the Gulf Stream will
spread west through the late evening and overnight, increasing a
bit in areal coverage. Lightning strikes and heavy rains appear
to be the main hazards.
Thursday through Monday: High pressure centered to the northeast
will prevail along with weak troughing at times locally. Expect
southerly winds 10-15 kt with gusts around 20 kt Thursday into
Friday morning. Although conditions off the southeast SC and GA
coasts could near Small Craft Advisory (SCA) criteria Thursday,
especially in the offshore waters and in Charleston Harbor, we
suspect the chances for SCAs are low. Seas should range 3-4 ft over
the waters through at least Friday evening, with 4-5 ft seas in the
outer Georgia waters beyond 20 nm. Mariners should be alert for
scattered thunderstorms, potentially even a strong storm or two,
through Saturday night. Conditions will improve by late weekend,
with seas decreasing to 2-3 ft and southeast winds around 10 kt.
Rip Currents: Moderate to strong onshore winds could enhance the
risk of rip currents tomorrow. For now, a moderate risk is forecast
Thursday for all beaches along Southeast South Carolina and Georgia.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
NEAR TERM...NED
SHORT TERM...
LONG TERM...
AVIATION...NED
MARINE...
Area Forecast Discussion
National Weather Service Corpus Christi TX
610 PM CDT Wed Jun 2 2021
.AVIATION...
Showers and thunderstorms are expected tonight and Thursday, with
periods of heavy rain possible. A few storms could be strong with
gusty winds and small hail. VFR conditions are expected through
the TAF period, with only periods of MVFR ceilings and
visibilities in and around any thunderstorms.
&&
.PREV DISCUSSION... /Issued 423 PM CDT Wed Jun 2 2021/
SHORT TERM (Tonight through Thursday Night)...
A destabilizing atmosphere has led to the development of showers and
thunderstorms across the Victoria Crossroads and northern Coastal
Bend this afternoon. Should see a break in activity this evening as
storms decrease in coverage with the loss of daytime heating;
however, a disturbance bordering a closed low will continue to drift
east towards the state overnight tonight, providing the opportunity
for isolated overnight convective development.
CAPE values overnight will be around 2000-3000 J/kg and there is
plenty of moisture as PWAT values range from near to above normal
values (1.7-1.9"). Current thought is that CIN will show a general
increase overnight with heating loss, which will limit convective
development; however, with high CAPE values and ample moisture,
could see isolated showers and thunderstorms due to mesoscale
factors.
As far as Thursday is concerned, am leaning more towards the HRRR as
it has initialized fairly well with this afternoon`s convection,
though majority of the models are in agreement that the atmosphere
will be quick to destabilize as daytime temperatures increase and
the closed low moves closer to the area. Current HRRR run brings an
MCS into the area tomorrow from the NW, but timing of arrival
remains tricky. At this time thoughts are that showers and
thunderstorms will be isolated to scattered in coverage during the
morning hours, becoming numerous in coverage by the afternoon.
The focus during the short-term period is the flooding potential. A
couple more inches of rain will be possible during the short-term
period, and ponding of water over already saturated soils is likely,
especially with any training or slow moving cells. WPC has the CWA
under a Marginal Risk for excessive rainfall tomorrow. Localized
flooding will be possible through the period. Interests in low-lying
or flood prone areas should remain vigilant for any weather updates.
Temperatures tonight into Thursday night will be normal to below
normal with partly to mostly cloudy skies and light southeasterly
winds. Highs will be in the low to mid 80s on Thursday with lows in
the 70s tonight and tomorrow night.
LONG TERM (Friday through Wednesday)...
The GFS and ECMWF generally agree with the timing/position of the
upper low over the region Friday/Saturday, followed by a gradual
dissipation/northward movement of the system Sunday/Monday. The GFS
predicts PWAT values above normal over the CWA Friday/Saturday, with
even greater moisture Sunday/Monday (PWAT values around 2 inches).
Expected scattered/numerous convection Friday/Saturday. Efficient
rainfall production anticipated at least on Friday and concur with
WPC regarding a Marginal Risk of excessive rainfall. As the upper
system gradually lifts northward Sunday/Monday, at least scattered
convection expected owing to copious moisture. Tuesday/Wednesday, a
Expect lingering moisture to contribute to isolated/scattered
convection.
MARINE...
Isolated to scattered showers and thunderstorms will be possible
across the coastal waters tonight. Coverage for showers and
thunderstorms will increase to scattered to numerous tomorrow
through tomorrow night as a disturbance pushes through the area.
Scattered/numerous convection Friday/Saturday, with a gradual
decrease in areal coverage Sunday/Monday. Isolated convection
Tuesday/Wednesday. Predominately weak to moderate onshore flow.
&&
.PRELIMINARY POINT TEMPS/POPS...
Corpus Christi 74 85 71 81 71 / 50 60 60 60 60
Victoria 72 83 71 81 70 / 40 60 60 60 60
Laredo 73 88 71 85 70 / 50 60 50 60 50
Alice 73 85 70 83 69 / 40 70 60 60 60
Rockport 75 85 73 84 72 / 40 60 60 60 60
Cotulla 72 87 71 85 70 / 60 60 60 60 50
Kingsville 74 85 71 82 70 / 40 60 60 60 60
Navy Corpus 76 84 74 82 74 / 40 60 60 60 60
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&
$$
LS/77...AVIATION
Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
838 PM CDT Wed Jun 2 2021
.UPDATE...
Adjusted the PoPs upward in the short term along and east of the
I-10/37 corridor as the 00Z HRRR, which has initiated fairly well
compared to previous runs, shows the current convective complex
advancing across that region. An isolated severe thunderstorm
remains possible with large hail and strong winds. Given heavy
rainfall rates, concern for flooding also exists where cells are
capable of producing 1 to 3 inches quickly. Additionally, still
showing some signals on models for a possible second convective
complex approaching from west Texas late overnight into Thursday.
&&
.PREV DISCUSSION... /ISSUED 650 PM CDT Wed Jun 2 2021/
AVIATION...00Z TAF Package
VFR conditions begin the period at the TAF sites and that trend
should continue throughout much of tonight. However, that depends
largely on the evolution of ongoing convection. Latest guidance
paints low confidence, but some activity may move into the region
from the Hill Country later this evening into tonight. The late
overnight hours through Thursday seems to feature the better
opportunity for possible impacts from rain and/or convection with
the possible approach of a complex of activity from the north-
northwest. However, placement and timing of any activity with the
complex is difficult to pinpoint and resulting in a overall low
confidence forecast. MVFR ceilings likely develop during Thursday
morning and will last through the remainder of the TAF period.
PREV DISCUSSION... /ISSUED 448 PM CDT Wed Jun 2 2021/
UPDATE...
Elected to make adjustments to the PoPs through the rest of today
and into tomorrow given the latest observational trends and hi-res
model guidance. Have generally lowered the PoP values through 12Z
Thursday. Highest concentration of scattered activity this evening
should continue to primarily focus across the Hill country into the
Travis/Williamson County area and across the coastal plains. Once
daytime heating is lost, models indicate that some kind of lull may
develop later tonight and into the overnight hours. The latest 18Z
HRRR and 3km NAMNEST then show the formation and/or the advancement
of a MCS across the region from early Thursday morning through the
day. Despite low confidence on exact timing and placement regarding
this complex, this will be when PoPs will be highest across South-
Central Texas over the next 36 to 48 hours.
PREV DISCUSSION... /ISSUED 224 PM CDT Wed Jun 2 2021/
SHORT TERM (Tonight through Thursday Night)...
A deep upper level trough extends from the Central Plains to the
northern Baja Peninsula this afternoon with southwesterly flow over
Texas. At the surface warm, moist air remains in place with
temperatures in the 80s and dewpoints in the middle 60s to the lower
70s. Isolated convection has begun over the eastern half of South
Central Texas. The forecast has changed very little today. The
southern part of the upper trough will close off during the next 12
to 24 hours and drift across northern Mexico. As shortwaves rotate
through this pattern they will initiate convection over the region.
This afternoon and evening conditions are conducive for strong to
severe thunderstorms across the northern part of our CWA where SPC
has issued a slight risk for large hail and damaging winds. South of
the slight risk is a marginal risk for most of the rest of South
Central Texas. PW values across the area are above 1.5" and this will
make locally heavy rain possible as well. Short term models a bit
scattered in their solutions for this evening. It`s hard to say
where convection will develop and move. But storms that do form will
be capable of producing a quick 1-2 inches of rain. Convection will
continue overnight and into Thursday. Timing and location are hard
to determine at this time. The airmass will remain essentially
unchanged, so locally heavy rain will be possible again Thursday and
Thursday night.
LONG TERM (Friday through Wednesday)...
The long term forecast shows some, but only little improvement to the
upper pattern. Friday, an upper low, currently over Baja, gets
absorbed into the trough before cutting back off over Texas. This
upper low hangs out though the weekend causing multiple rounds of
showers and storms at various locations spread throughout the CWA. So
with little time to recover from the saturated soils from previous
rain, areas will need to be monitored for flash flooding and/or river
flooding.
By early to mid-week next week, the upper low over Texas moves
northeast while the upper ridge peeks in from the west. For the rest
of the long term forecast, POPs will be split west to east, with rain
chances east and dry out west.
Temperatures through the long-term stay below normal with highs in
the 80s through the period.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 68 81 68 80 68 / 70 60 40 60 50
Austin Bergstrom Intl Airport 68 81 68 80 67 / 70 60 40 60 50
New Braunfels Muni Airport 70 82 68 82 68 / 50 60 40 60 50
Burnet Muni Airport 66 80 66 79 66 / 70 60 30 60 40
Del Rio Intl Airport 72 86 69 84 69 / 30 50 40 60 40
Georgetown Muni Airport 67 81 67 80 67 / 70 60 30 60 40
Hondo Muni Airport 68 82 67 80 66 / 40 60 40 60 50
San Marcos Muni Airport 69 82 67 81 67 / 60 60 40 60 50
La Grange - Fayette Regional 70 84 70 82 70 / 40 60 40 60 50
San Antonio Intl Airport 70 81 68 80 68 / 50 60 50 60 60
Stinson Muni Airport 71 83 70 82 69 / 40 60 40 60 50
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Short-Term/Aviation...Brady
Long-Term...Platt
Area Forecast Discussion
National Weather Service Green Bay WI
1056 PM CDT Wed Jun 2 2021
Updated aviation portion for 06Z TAF issuance
.SHORT TERM...Tonight and Thursday
Issued at 234 PM CDT Wed Jun 2 2021
The latest RAP analysis and satellite/radar imagery show a
shortwave trough tracking across the northern Mississippi Valley
early this afternoon. Ahead of the trough, 800 j/kg of surface
based cape has developed ahead of an alto-stratus cloud deck,
which contributed to convective clouds and isolated showers and
storms. With further destabilization, additional showers and
storms are possible to develop through the afternoon, but weak
forcing should limit coverage to isolated or scattered in nature.
Small hail and brief gusty winds will be possible in the strongest
storms. The greatest coverage should occur north of HWY 29 from
Green Bay to Wausau. With another shortwave due to track into the
region tomorrow, coverage and timing of the showers and storms are
the main forecast concerns over the next 24 hours.
Tonight...The shortwave over Minnesota will continue to move east
and across the region. Though a diminishing trend of the storm
activity should occur with the loss of daytime heating, think will
see isolated storms persist through the evening as a result of the
shortwave. Unsure how long the precip will extend through the
night so didn`t stray to far from the previous forecast. But will
show isolated activity ending after midnight. Temperatures will
fall into the 50s at most locations.
Thursday...Another shortwave trough will track towards the region
during the afternoon. Convective temps will remain in the upper
70s to around 80 degrees across northern WI, which will promote
mixed layer instability growing to upwards of 1000 j/kg in the
afternoon. Therefore, will see another chance for showers and
thunderstorms across the region. Deep layer shear will be a little
stronger than today and upwards of 25 kts. So while severe
weather is not anticipated, some of the stronger storms could
produce small hail and wind gusts around 45 mph. Forecast moisture
convergence points towards areas north of HWY 29 from Green Bay
to Wausau should see the highest coverage of thunderstorms. High
temperatures will be warmer than today and range from the upper
70s to middle 80s.
.LONG TERM...Thursday Night Through Wednesday
Issued at 234 PM CDT Wed Jun 2 2021
The most notable weather during this period will be the well above
normal temperatures with daytime highs well into the 80s and some
lower 90s over the weekend. The weekend looks free of rain and
thunderstorm.
Thursday night through the weekend...The upper trough will
depart the area Thursday night and instability will wane with the
loss of daytime heating. Therefore, continued a chance of showers
and thunderstorms into the evening with only a slight chance
after midnight. After this activity fades dry weather is expected
through most if not all of the weekend. Upper ridge will build
across the northern Plains and into the Great Lakes, while a
surface high in the southeast CONUS will allow for southwesterly
flow into WI. This will lead to mostly sunny conditions along with
a warmer and more humid airmass. High temps will be in the mid
80s to low 90s on Friday, and in the upper 80s and low 90s
Saturday and Sunday. Dew points will generally be in the 60 to 65
degree range, which will feel humid, but not quite as tropical as
upper 60s low 70s Tds. Winds will also be somewhat breezy from the
southwest over the weekend. This could lead to some high waves
along the Lake Michigan shoreline for any beach-goers hoping to
find relief from the warm weather.
Early next week...Model differences arise on timing and location
for any showers or thunderstorms. There will likely be scattered
activity, but low confidence in pinpointing when and where at
this time. Used a blended model solution which features chance
PoPs each day, especially during the afternoons and evenings.
Meanwhile, slightly cooler 850mb temps and more clouds will cause
temperatures to fall back a few degrees, but will still remain
above normal with highs in the 80s.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 1056 PM CDT Wed Jun 2 2021
Scattered to broken CU will drift slowly east through the rest of
the night as an upper-level trough axis is slow to exit northeast
Wisconsin. Ceilings and visibilities are expected to remain VFR;
however, RHI could see some ground fog develop overnight. A few
stray showers are possible, but are not likely to impact any of
the TAF sites. Yet another system will pass through the area
Thursday, bringing another chance of showers and thunderstorms,
especially at at AUW/CWA/RHI. This would be late toward the end of
the TAF period. Confidence is low enough to leave out of the TAF
with this issuance, but may be needed with later updates as
confidence increases.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......KLJ
AVIATION.......Cooley
Area Forecast Discussion
National Weather Service Houston/Galveston TX
853 PM CDT Wed Jun 2 2021
.AVIATION [00Z TAF Issuance]...
A couple spots of active weather did (and still continuing to) have
impacts on our airports this evening. Fortunately, the cells around
CLL have dissipated, but are persisting near IAH. Will expect most/
all of these storms to dissipate in the next hour (or so) given the
loss of heating. A few locations with MVFR CIGS possible once again
overnight/early tomorrow morning. Otherwise, no real change for to-
morrow afternoon with the approach of another shortwave and chances
for thunderstorms. 41
&&
.PREV DISCUSSION... /ISSUED 338 PM CDT Wed Jun 2 2021/
SHORT TERM [Through Thursday Night]
Convective temperatures have been met and showers and thunderstorms
have begun to develop across SE TX. Some training of storms has also
developed and some locally heavy rainfall totals will be possible
through this evening. The HRR continues to insist that shra/tsra
will will focus along a weak boundary/wind shift that is anchored
over the central zones while the HiRes NSSL focus precip over the
southern zones. The 18z HRRR initialized well bu the NSSL has
verified better as of late. Will compromise between the two models as
both could be correct as there is some low level convergence along
the central CWA boundary as suggested by the HRRR and and also along
the developing sea breeze as suggested by the NSSL. SE TX also will
lie in a weak RRQ this evening and this feature will also help to
enhance lift. Colliding boundaries between the weak front and the
sea breeze could allow for a burst of heavier convection this
evening and have added locally heavy rain to the wx grids through
03z in case that situation unfolds. Colliding boundaries can also
lead to storm intensification and a brief pulse strong to severe
storm can not be ruled out. Damaging winds, brief funnel clouds and
small hail are the most likely severe weather hazard and SPC has
placed much of SE TX in a Marginal Risk for strong storms tonight.
With sfc dew points above 70, MinT values will remain on the warm
side and will probably stay in the lower 70s except in some rain
cooled locations.
On Thursday, a short wave will approach SE TX by late morning. There
should be an expanding area of showers and storms Thursday morning
as this feature approaches. Jet dynamics still look somewhat
favorable on Thursday as 300 mb winds gently split over SE TX.
Moisture levels will remain robust with PW values near 2.00 inches.
Storm motion looks a tad slower on Thursday as well so once again
there will be some potential for locally heavy rain. There will be
more cloud cover on Thursday and precip should be a bit more
widespread so will trim MaxT values by a few degrees from today`s
values. Despite the risk for locally heavy rain tonight and again
Thursday, will once again forgo a Flash Flood Watch until there is a
better signal for more widespread rainfall and an organized flash
flood threat.
Rain chances should decrease but not completely end on Thursday night
in the wake of the initial short wave. However a second short wave
will be approaching late Thursday night and showers and
thunderstorms will likely be on the increase prior to sunrise
Friday. 43
LONG TERM [Friday Through Wednesday]...
Environmental conditions look to become more favorable for a
multi-day active weather pattern Friday through the upcoming
weekend, possibly extending into early next week. This will
ultimately increase the risk for potential flooding across
portions of SE Texas.
To start, an upper level low will be located over Northern Mexico
and Western TX Friday with the elongated associated trough
extending northeastward well into the Great Lakes region. As high
pressure builds over Western CONUS, the top region of the trough
over the Great Lakes will continue eastward, while the upper low
and the base of the trough remains almost stationary over Northern
Mexico and Western TX. The upper low closes by late Friday and
remains meandering over most of Texas during the weekend...which
brings an upper level jet close or over the CWA (possible
diffluence to occur) favoring storm development. In addition, a
few mid to upper level disturbances will be swinging along the
base of the trough and move across SE Texas. On top of all of
this, we are looking at very good low level moisture transport
with the southerly flow increasing PWs between 1.8 to 2.1 inches
areawide, possibly resulting in long periods of heavy rainfall,
particularly on Saturday. Now moisture does ebb a bit on Sunday
with PWs down to 1.5 to 1.7 inches, however, it may still be
sufficient for a few more rounds of showers and thunderstorms to
occur given that we`ll have the upper low/trough moving closer
into Southeast TX. Global models weaken the trough early next week
but PWs bounce back to around 1.8 to 2.1 inches Monday and
Tuesday, enough to maintain additional periods of rain. Thus, we
are looking at good chances for rain to fall over our area Friday
through early next week.
WPC is forecasting QPF amounts of 4 to 7 inches of total rainfall
amounts during the next 7 days, with the heavier totals to occur
Saturday through Monday. Considering the spectrum of expected
rainfall amounts, along with the fact that we still have fairly
wet soils lurking across portions of the CWA and water levels
running high in a few of our rivers, this next episode of active
weather could result in some flooding issues. Flash Flood Watches
may be issued later this week, stay alert and prepared in case one
is issued for your area. High pressure trying to start building
sometime mid to late next week, means lower rainfall chances -
hopefully it builds giving us a break from the stormy weather.
High temperatures each day will be in the low to mid 80s through
early next week, increasing a few degrees by midweek, and low
temperatures will generally be in the upper 60s to low 70s inland,
mid 70s along the coasts.
-- Given it`s the long term period, changes to the forecast could
occur, although at this time, most models are in fairly good
agreement with the long term synoptic pattern.
24
MARINE...
Light winds will continue through the end of the work week across
the bays and waters along with seas of 1-3 feet. Winds increase
Friday into the upcoming weekend possibly reaching the Caution
threshold. Seas build to 4-6 feet by late Sunday into Tuesday.
Chance of showers and thunderstorms can be expected each day
Thursday through early next week, with the heaviest activity
expected to occur Friday through Sunday. Tides levels may also
increase Sunday into early next week.
For those planning to visit the beaches this weekend, strong rip
currents could occur across the Gulf facing beaches. Make sure to
monitor the local beach advisories.
24
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 69 83 70 82 69 / 40 70 30 60 40
Houston (IAH) 70 85 71 82 70 / 50 70 20 70 50
Galveston (GLS) 76 83 75 82 75 / 20 40 40 70 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1045 PM EDT Wed Jun 2 2021
.UPDATE...
Issued at 1045 PM EDT WED JUN 2 2021
Much of the forecast is on track. Have loaded in the latest obs
and blended into the forecast for t, td, and winds. Have added in
the latest sky trends, as there is some clearer skies along the
southwest and into Louisville`s CWA. PoPs were dialed down in
some locations given the lack of activity, but have continued to
keep slight chance in to account for the light returns seen on
radar. Grids have been sent to NDFD and webfarms.
UPDATE Issued at 814 PM EDT WED JUN 2 2021
Changes with the update were minimal with the biggest tweaks in
the temperature grids. Some locations were falling a bit quicker
than forecast given the cloud cover and rain-cooled air. The
latest obs were data load and blended for temps, dews, and winds.
The remainder of the forecast remains on track.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 510 PM EDT WED JUN 2 2021
Model are in good agreement. Aloft, trough stretching from the
Great Lakes southward into the lower Mississippi Valley and
Southern Plains will shift into the eastern CONUS by late Thursday
night. At the surface, a wave of low pressure over southern IL
will continue to track northeast, first lifting a warm front
north of eastern Kentucky tonight and then pull a cold front
through the area Thursday night.
Sensible weather features a stormy short term. The potential for
thunderstorms will transition from an elevated to a surface based
by tomorrow. MLCAPEs will climb to between 1000-1500 J/kg with
30-40 kts effective shear, enough for some organized convection.
Lapse rates aloft are not impressive, but boundary layer lapse
rates are moderately steep. Interestingly, a sampling of CAM
soundings do show some mid level drying and ample effective shear
that some marginally large hail will be possible. In addition, the
hrrr indicates some 0-3 km CAPE in excess of 150 J/kg matched up
with some areas of surface based vorticity. If boundary layer
lapse rates were a bit stronger, one really could not rule out an
isolated tornado. Overall the greatest, main threat is still
damaging wind gusts. This is currently addressed in the HWO.
Threats will continue to be monitored for any potential changes.
.LONG TERM...(Friday through Wednesday)
Issued at 300 PM EDT WED JUN 2 2021
Fairly active weather is anticipated in the extended portion of
the forecast. A trough of low pressure aloft that will be exiting
the area on Friday, should allow scattered showers and a few
storms to linger across eastern Kentucky through early Friday
evening. Once this trough exits to our east, we can expect a
mostly dry weekend around our area. Drier air will filter in
behind the departed weather system Friday night and Saturday, and
will allow things to dry out quite nicely through early Sunday
afternoon. The drier air, combined with light and variable winds
and mostly clear skies, will allow temperatures to warm well into
the 80s by late Saturday afternoon. In fact, this warming trend
should continue through the middle of the upcoming work week.
Daily temperatures will average out in the mid to upper 80s each
day next week, with nightly lows in the 60s on tap as well, as
winds will be primarily out of the south or southwest along the
back edge of a large ridge of high pressure.
We should see precipitation chances each day during the extended
from late Sunday onward, as warm, moist and unstable off the Gulf
of Mexico flows into the region along the western edge of what we
call a "dirty ridge" of high pressure. Daytime heating, combined
with the low level moisture, should produce enough instability and
lift to spark showers and storms each day, with any storms
occurring primarily during the afternoon and early evening hours.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
ISSUED AT 814 PM EDT WED JUN 2 2021
VFR conditions are expected through the beginning of the period
before ceilings deteriorate after dawn. A warm front will be
lifting across the area to the north tonight. That will leave the
area in the warm sector of this storm system along with more
boundary layer moisture and surface based instability. Thus CIGS
will eventually drop on average into solid MVFR territory. With
diurnal heating, the threat of thunder will be greater during the
day Thursday as well, with best chances during the
afternoon/evening time frame, toward the end of the forecast.
Winds will be generally light, around 5 kts or less and variable,
but will become southerly Thursday behind the passing warm front.
Some non-convective LLWS will be possible for our more northern
terminals for a few hours in the predawn Thursday courtesy of a
moderate 40-45 kt H850 jet.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BB
SHORT TERM...RAY
LONG TERM...AR
AVIATION...BB/RAY/KAS
Area Forecast Discussion
National Weather Service New Orleans LA
1000 PM CDT Wed Jun 2 2021
.EVENING UPDATE...
Still a band of scattered showers and storms about 30 miles wide
from Tylertown southwest toward Baton Rouge and Lafayette. Locally
very heavy rain with one or two cells producing 2-3 inches in an
hour in a couple of spots. HRRR would indicate a diminishing trend
in the near-term, but a refiring of isolated to scattered
convection prior to sunrise across portions of the area.
00z LIX sounding remained unstable with a precipitable water value
of 1.77 inches. That was launched about 40 minutes after a storm
dropped 0.26 inch of rain in 5 minutes at the ASOS. Considering
the 00z sounding, the 00z HRRR solution and a similar scenario
last night, will hold precipitation chances in the forecast for
the remainder of the night, per earlier package. 35
&&
.PREV DISCUSSION... /issued 410 PM CDT Wed Jun 2 2021/
SHORT TERM (Tonight through Friday Night)...
Active pattern will persist as upper level troughing stretching
from New England southwestward through Texas keeps the local area
in southwest flow aloft with a series of embedded disturbances
passing through the area firing off scattered to numerous showers
and storms as they transit the area. Greatest coverage should
generally be during the afternoon to early evening hours aided by
daytime heating. Not anticipating any stalling storms, but could
see locally heavy rainfall become a problem if any specific area
sees multiple rounds of storms in a relatively short time. Area
average rainfall over the next couple days is generally around an
inch, but expect that a few places will likely see higher amounts.
LONG TERM (Saturday through Tuesday Night)...
Active pattern continues through the weekend and into the first
part of the week, though Saturday may be slightly less active.
Am carrying likely to categorical POPs Sunday through Tuesday. PW
values approaching 2 inches look to be likely, which would easily
lead to some efficient showers and storms. Generally carrying 1-3
inches of rain during the Sunday through Wednesday time frame and
undoubtedly some places will see substantially higher totals than
that. Still looks like area least at risk of heavy rainfall is the
MS coastal counties, though it can`t be ruled out entirely if a
few storms align just right.
AVIATION...
Outside of showers and storms, VFR conditions should prevail
through most of the period. Patchy fog/low stratus could result
in MVFR or IFR conditions for a few hours near daybreak.
Otherwise, attempted to time any showers/storms that might affect
the terminals by inserting TEMPO groups, but short term amendments
may be needed at times to account for showers/storms outside of
those windows.
MARINE...
High pressure to the east will continue to promote onshore winds
through the remainder of the week, with relatively light winds
and low waves/seas. Winds averaging around 10-15kts can be
expected during the afternoon hours each day, with occasionally
higher gusts to gentle/moderate breeze. Scattered showers and
thunderstorms will be possible at any point through the upcoming
weekend and into early next week, with better coverage across
protected and near shore waters. The main threats in any one
stronger storm will be locally gusty winds, increased waves/seas
and dangerous lightning.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 70 85 69 84 / 50 60 30 50
BTR 72 85 71 84 / 40 70 20 60
ASD 72 86 71 85 / 40 60 20 50
MSY 75 87 75 85 / 30 60 20 50
GPT 74 85 73 85 / 40 50 20 50
PQL 72 85 71 86 / 30 40 20 50
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&
$$
Area Forecast Discussion
National Weather Service Louisville KY
1006 PM EDT Wed Jun 2 2021
.Forecast Update...
Issued at 1006 PM EDT Wed Jun 2 2021
Watching storms near Clarksville, Tennessee as they push to the
east. As they developed they showed a fair amount of organization
and were on the axis of a very narrow corridor of 2000-2500 J/kg
SBCAPE. Current mesoanalysis suggests that if they can maintain
their current level of organization they may edge into Logan County
before encountering more significant convective inhibition to the
east towards the I-65 corridor.
A small area of storms trained over the northwest corner of Dubois
County just enough to warrant the issuance of a Flood Advisory for
areas mainly west of Portersville where 1-2" of rain may have fallen
right along the East Fork of the White River. Convection in that
region continues but is weaker and more widely scattered. The main
threat for heavy rain should be east of there after 11pm EDT.
Showers and thunderstorms will become more widespread as we go
through the night, with locally heavy downpours as the primary
threat after midnight. Gusty winds with the strongest cells will
also be possible, but should be sub-severe given weak DCAPE and low
level lapse rates.
Issued at 630 PM EDT Wed Jun 2 2021
Low pressure is just southwest of Paducah with a narrow warm sector
poking northward into the Jackson Purchase and Pennyrile. Ahead of a
surface boundary lined up along the Mississippi River, skies
partially cleared this afternoon and thunderstorms blossomed from
Land Between the Lakes to the central Gulf Coast. These storms are
mostly in an area of weak/marginal mid-level lapse rates and
marginal deep shear. They have stayed largely sub-severe with only a
handful of warnings issued and just a couple reports of severe
weather so far (including a 75mph gust at the Jackson, MS airport).
Closer to home, robust convection that initially developed over
southwest Kentucky has recently begun to struggle with
reflectivities decreasing and storm tops warming.
Better wind energy aloft is located well to the east, with the
storms depending largely on diurnal instability. As we head into the
evening hours and CIN increases, the chances of severe weather will
diminish further. Through sunset WoFS keeps severe weather out of
central KY and central southern Indiana, though isolated
thunderstorms will still be possible west of I-65.
Shower and elevated thunderstorm activity should increase after
midnight as the low level jet strengthens from the Tennessee Valley
into the eastern half of Kentucky and a 5H trough over the
Mississippi Valley approaches. Given precipitable water values
around 1.5", any training storms would be capable of dropping
locally significant rainfall amounts late tonight.
&&
.Short Term...(This evening through Thursday)
Issued at 255 PM EDT Wed Jun 2 2021
15z sfc analysis shows the sfc low is located over southern MO and
tracking to the northeast. As it continues its northeastward track
this afternoon and evening, it will lift the eastward extending warm
front currently located over the TN Valley northward along the Ohio
River. This will place our CWA within the warm sector of the low
pressure system, with sfc temps in the low to mid 70s expected along
with dewpoints in the low to mid 60s. Further west, the Kentucky
Mesonet currently reveals temps reaching the 70F mark under some
clearing skies. Sky cover guidance for this afternoon and evening
continue to suggest our area will remain under mostly cloudy skies
through the afternoon.
LLJ is evident on the KLVX VAD wind profile, with south winds of
35kts around 3k ft helping to advect rich Gulf air into the region
and increased PWATs to 1.6". SPC mesoanalysis shows decent
destabilization to our west with SBCAPE of 1500-2000 J/kg, but
rather stable air over our CWA. Additionally, RAP forecast soundings
and RAP/SfcOA fcsts suggest some instability this evening in the
neighborhood of 1000 J/kg in a region west of I-65. However, with
the LLJ departing to the ENE, best wind energy (shear and SRH) will
be located ahead (east) of the best instability environment through
this evening. Cant rule out some strong or gusty thunderstorms over
southern IN or areas west of I-65 in KY, but appears our overall
severe risk is low.
Overnight, a few scattered showers are possible, but the CAMs show
come consistency on showers along our eastern CWA tomorrow morning
before 14z or so. Another round of showers and some storms come
tomorrow afternoon as diurnal heating regenerates the cold front
sitting across the region. Scattered showers and storms are possible
through the afternoon and early evening hours of tomorrow as SBCAPE
possibly reached 1000-1500 J/kg. Storms look to be more pulse like
and disorganized with the lack of shear to work with. Tomorrow`s
temps should reach the mid-upper 70s.
.Long Term...(Thursday night through Wednesday)
Issued at 245 PM EDT Wed Jun 2 2021
Thursday evening could see lingering convection, mainly east of I-65
as the afternoon impulse departs. Continuing risk will be marginal
at best, and diminishing at that, but we can`t rule out some small
hail given WBZ heights around 10K feet and moist adiabatic mid-level
lapse rates.
Friday will be warm and mostly dry under a bubble of sfc high
pressure, but NW flow and lingering trofiness aloft could support at
least isolated diurnal convection. Heights will build through the
weekend, so we will have a dry Saturday with temps near normal for
early summer.
From Sunday onward, upper low gets better organized over Texas, and
ridging builds over the eastern CONUS to set up southerly flow
through a deep layer. The most efficient moisture feed will be over
the Mississippi Valley, but we`ll have isolated to scattered
convection each afternoon. Clouds and precip will modulate temps
through mid-week, with daytime temps near climo and increasingly
warm and muggy nights.
&&
.Aviation...(00Z TAF Issuance)
Issued at 748 PM EDT Wed Jun 2 2021
IMPACTS: Shower/storm chances, low ceilings
DISCUSSION: Low pressure near PAH this evening will move up the Ohio
River tonight and pull a cold front through the region tomorrow. As
long as we are ahead of the cold front scattered showers and
thunderstorms will be a possibility. There may be an uptick in
convective coverage during the pre-dawn hours as the low level jet
increases...especially affecting LEX. Another period of increased
thunder possibility will be tomorrow afternoon ahead of the front,
again especially at LEX.
Mesoscale models have been consistent showing IFR/LIFR ceilings and
lowered visibilities at HNB late tonight into Thursday morning in
moist, stagnant air just on the cool side of the passing surface
low. Patchy low ceilings are already present from southeast Illinois
to southwest Ohio. So, will continue to include that in the HNB TAF.
CONFIDENCE: Low on shower/tstorm timing, medium on ceilings, high on
winds
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&
$$
Update...13
Short Term...CJP
Long Term...RAS
Aviation...13
Area Forecast Discussion
National Weather Service Marquette MI
717 PM EDT Wed Jun 2 2021
.SHORT TERM...(This evening through Thursday)
Issued at 451 PM EDT WED JUN 2 2021
Water vapor imagery and RAP analysis show a ridge over western N
America. Axis of downstream troffing extends from Hudson Bay to
eastern TX. Within this trof, a shortwave is moving into the
northern Great Lakes. MLCAPES have increased to around 500j/kg
across central Upper MI where there was morning/early aftn sun.
Shortwave and the instability have led to sct -shra/tsra developing
over the last few hrs. Small hail and gusty winds to around 40mph
have accompanied the strongest storms.
Sct -shra/isold tsra across central Upper MI will continue moving e
over the next few hrs. Expect a diminishing trend into the eastern
fcst area as air mass is more stable due to the southerly flow off
Lake MI. Fcst then gets more uncertain. Clouds are breaking over the
w, and instability may surge upward before daytime heating is lost.
High based cu are redeveloping in that area and may be harbinger of
renewed shra/tsra in the next couple of hrs. Fcst will reflect at
least schc pops across much of the fcst are thru late evening to
cover potential redevelopment. The overnight should be quiet though
shortwave dropping thru northern Ontario may support additional
convection at least over portions of Lake Superior late. If so, shra
may affect areas east of Grand Marais Thu morning.
Fri looks like a repeat of today. Mid-level trof axis will extend s
across the Great Lakes with another shortwave arriving for peak
heating. Consensus is for MLCAPE to be higher than this aftn with
values probably in the 500-1000j/kg range. There is more model
spread with the potential deep layer shear. Lower end is around 20kt
while higher end is 30-35kt. Higher end would certainly support some
storm organization and a svr risk while the lower end would offer
only the potential of isold strong storms and perhaps a pulse type
svr risk. In any event, it does appear that storms will be stronger
than today. Expect most of the convection to occur mid to late aftn
with central Upper MI seeing the greatest coverage. Expect the s
central to have the best chc of stronger storms and potentially an
isold svr.
.LONG TERM...(Thursday night through Wednesday)
Issued at 437 PM EDT WED JUN 2 2021
Above-normal temperatures with few chances for precipitation are in
store for this longterm period. West Coast ridging and troffing
across the central CONUS to begin period will begin to shift East
through the week as a cutoff system shifts into the southern Plains.
This will lead to well above-normal temperatures across Upper
Michigan, though, there shouldn`t be a deep, Gulf Moisture feed this
time around with the cutoff system keeping the upper-level flow more
westerly. This isn`t to say it will be a dry heat, though, so make
sure to drink plenty of water and keep the sunscreen handy through
the weekend. By early next week, models suggest troffing to take
over off the West Coast as broad ridging shifts a bit more east
across the Great Lakes and eastern CONUS. Models do suggest some
Gulf Moisture to lift through the Plains into the Upper Midwest, but
models show some diverging solns during the middle of next week with
some uncertainty building.
On Thursday night, Upper Michigan will be on the east side of an
approaching ridge as the longwave trof begins to shift into New
England. There could be some isolated thunderstorms across the south
central early in the evening, but then some clearing should begin.
By Friday, the warmup begins with 850mb temps warming up to around
18 to 20C by the afternoon across the west half. This should bring
some chances for 90 across the interior west, with low 80s east.
Another warm day on Saturday, with widespread 90s across the west
and central looking likely. There looks to be some breezy west to
southwest winds Saturday, which should limit temps downwind of Lake
Michigan. Attention then turns to Sunday, where drier mid-level air
works into the region with gusty SW winds. Did end up lowering RHs a
bit from the NBM given the deeper mixing potential. Winds at 925mb
look to be around 30 to 35 knots as well. If deeper mixing is able
to occur, there could be a chance at critical fire weather concerns
with min RHs into the 20s, max temps near 90 and gusts to around 25
mph. This will need to be monitored over the coming days as Upper
Michigan is still running through a bit of a dry spell.
Models diverge a bit into next week, but the overall warm and drier
trend looks to remain. A weak wave moving through on Monday could
bring some pcpn as a front passes to the north of the UP along the
upper-level ridge well into Canada. Sometime during the middle of
next week, models suggest the cutoff wave across the Southern Plains
will begin to lift north through the Plains, which could bring some
add`l pcpn chances, but any organized development seems unlikely at
this time. Humidity does look to increase as some gulf moisture
increases into the region as the upper-level ridge shifts east.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 702 PM EDT WED JUN 2 2021
As the earlier convective activity continues to wane and push
eastward, this will generally allow for less concern of impacts
direct to terminals. There is a lingering chance of a shower or
two popping up early in the TAF period near KIWD, but currently,
the radar looks quiet in N. WI. However, showers and thunderstorms
look to return to the central portions of Upper Michigan tomorrow,
and have therefore included a VCSH mention at KSAW to account for
this. Confidence remains low at this time until time approaches
for any TS mention, but will be possible for planning purposes. As
for winds, outside of any convective/shower activity, they should
continue to remain around or less than 10 knots through the
period, with generally southerlies to southwesterlies prevailing
overnight into early Thursday, becoming more westerly as the day
progresses.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 451 PM EDT WED JUN 2 2021
Expect winds across Lake Superior to be mostly under 20kt into Fri.
Stronger winds are then possible on Fri night as low pres moves e
across northern Ontario. Wind gusts of 20-25kt, even up to 30kt, at
the high obs platforms, will be possible Friday night into Sat
morning. The strongest gusts should occur btwn Isle Royale and the
Keweenaw. Another period of stronger winds is possible Sat night
into Sun as another low pres moves e to southern Hudson Bay.
Although the air mass will be very warm, resulting in very stable
conditions over the waters, sw to s winds could occasionally gust to
25kt to perhaps as high as 30kt at high obs platforms at some
point Sat night and Sun.
Fog may become an issue in the coming days as air mass over the area
becomes increasingly humid. However, will probably need to wait for
rainfall to occur into the chilly marine layer to get significant
fog to develop.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Rolfson
LONG TERM...JAW
AVIATION...lg
MARINE...Rolfson