Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/27/20
Area Forecast Discussion
National Weather Service Denver/Boulder CO
912 PM MDT Fri Jun 26 2020
.UPDATE...
Issued at 908 PM MDT Fri Jun 26 2020
Updated the forecast to expire the watch and adjust current
temperatures. Severe convection has died out for the most part,
and what`s left has exited the forecast area. A few lingering
thunderstorms quickly diminishing as the atmosphere stabilizes.
&&
.SHORT TERM...(This evening through Saturday)
Issued at 130 PM MDT Fri Jun 26 2020
Main concern is still severe weather potential through this evening
across much of Eastern Colorado. Severe thunderstorm watch has
already been issued for all of Eastern Colorado until 03z. Primary
threats still will be damaging winds up to 70 mph, large hail and
heavy rain. Still a few tornadoes are possible especially over the
Palmer Divide with southeasterly convergent flow expected there
this afternoon.
As for stability on the plains, latest ACARS soundings still
showing a weak inversion given a 81/50 temperature/dewpoint with
still some CIN over the plains. Current cloud cover from anvils
also limiting additional heating and Denver metro area may be
spared the worst of the severe weather. On the other hand the
Palmer Divide again looks to be the focus with still good heating
and CAPE values now approaching 2000j/kg based on latest LAPS
analysis. As storms shift east over the plains later this afternoon
and evening, looks like linear, cluster of storms will become
more outflow dominated with strong winds the main impact. HRRR
peak wind gusts showing these strong winds over Lincoln and
Washington counties up to 60kt. Storms will be diminishing from
west to east by later this evening.
On Saturday, the upper trof across northern Utah will gradually
shift across Colorado Saturday afternoon and evening. This feature
will help to spark another round of convection. Temperatures will
be warmer with readings back into the mid and upper 80s. The
atmosphere will be a bit drier with precipitable water values
down between a half and 3/4 of an inch while dewpoints will be a
bit lower in the 40s at least over the Front Range. Forecast
soundings showing more inverted v type profile over the Front
Range with more return to our "new normal" outflow winds being the
main threat. Appears the focus for the stronger storms will be
east and south of Denver along some convergence with strong
southeasterly flow across the Palmer Divide and stretching
northeast through Washington counties. SPC has the area under a
marginal risk and this looks good for main impact of strong winds
and possibly large hail.
.LONG TERM...(Saturday night through Friday)
Issued at 215 PM MDT Fri Jun 26 2020
Upper trough will be directly over the area Saturday evening, to
help sustain ongoing storm activity out over the eastern plains,
while areas further west will be quickly drying out. Could still
be some strong storms ongoing as they head further east out of the
state by midnight. Cooler minimum temperatures are expected
overnight, and clearing skies will allow mountain locations to see
readings dipping into the 30s.
An upper low dropping southeast over the Pacific Northwest Sunday
will dig its trough south into the Great Basin and down over
Southern California through Monday. This will increase
southwesterly flow across the state, ushering in warmer and drier
air over the state each day. Readings in the mid 90s to near 100
will be across the plains, with 60s to near 80 in the mountains
and high valleys. Scattered to numerous high terrain thunderstorms
Sunday afternoon will decrease to only isolated by Monday. Winds
will be increasing over the high terrain and eastern plains,
especially Monday in advance of an expected cold front. Will keep
an eye on speeds as humidity will be in the 10 to 15 percent
range over the plains.
The main energy of the trough will end up lifting northeast across
the Northern Rockies back into Canada Monday night into Tuesday,
dragging the trough across the area. A cold front is expected to
push down around the same time to bring upslope flow, cooler
temperatures and higher moisture, resulting in higher CAPE. Wind
shear looks to increase as the upper jet over the area combines
with the upslope flow for better chance for stronger
thunderstorms Tuesday afternoon. Wednesday will remain cooler,
with more stable and dry conditions.
An upper high will be building up from Old Mexico and West Texas
for Thursday and Friday to bring warmer temperatures. Just enough
subtropical moisture caught up under the ridge looks to keep in
diurnally driven afternoon and evening thunderstorms.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 534 PM MDT Fri Jun 26 2020
Showers and thunderstorms in the TAF site vicinity and will
continue until 02z. Wind gusts to 30 mph, small hail, and very
heavy rainfall possible with storms. After storms clear, wind will
settle down to southwest through the night with VFR. Another
round of high based thunderstorms with gusty wind potential
Saturday afternoon after 20-21z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Hanson
SHORT TERM...Entrekin
LONG TERM...Kriederman
AVIATION...Hanson
Area Forecast Discussion
National Weather Service Burlington VT
1006 PM EDT Fri Jun 26 2020
.SYNOPSIS...
Seasonably warm today with isolated showers this evening. An
area of low pressure will pass to our south bringing increased
rain chances, mainly along the Adirondacks and across Rutland
and Windsor Counties of Vermont during the afternoon hours on
Saturday. Periodic chances of showers and thunderstorms will
continue next week with a trend towards above normal
temperatures in the second half of the week.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
As of 1000 PM EDT Friday...The light showers and sprinkles that
impacted our cwa earlier this evening have weakened with partly
to mostly cloudy skies. Watching upstream MCS over southern MI,
which given the westerly 700 to 500mb flow per RAP analysis
looks to pass to our south on Saturday. Expecting the axis of
heaviest rainfall to be acrs central NY into southern New
England. However, weak embedded vort will interact with some
instability to produce a threat for showers and storms on
Saturday aft/evening, especially western cwa. Crnt fcst of
chc to likely pops on Sat looks reasonable, not expecting a wash
out acrs our cwa attm. Temps tonight mainly lower 50s to l/m 60s
and highs on Sat 70s to near 80 most locations.
Previous discussion below:
The base of an upper trough is swinging into the North Country.
Temperatures have climbed into upper 70s to mid 80s, with
efficient warming likely aided by dry boundary layer conditions.
Several light showers have developed along and ahead of the
boundary which is currently near St. Lawrence County, New York.
This will gradually continue eastwards this evening into
tonight. Mostly dry conditions are expected overnight. Light
southerly winds and relatively clear skies should result in lows
a degree or two warmer than this morning.
A compact shortwave, influenced by convection taking place now over
Wisconsin and Illinois, will head towards the Mohawk Valley. Zonal
flow aloft will keep moisture struggling to lift northwards into our
area as it crosses the Northeastern US. Portions of Essex County, NY
and Rutland/Windsor Counties in Vermont should be clipped by some of
the favorable dynamics and moisture associated with the feature, and
thus have the greatest chance to see around 0.25"-0.33" of
precipitation as the feature slides south across the region. While
most of the instability will be elevated, cannot rule out a rumble
of thunder. A sharp gradient to the north will mean the rest of our
region sees a few hundredths. Exact placement is still somewhat
changeable given how quickly errors can develop from convective
processes, so some adjustments north or south are still possible.
Analogs suggest the Mohawk Valley should be the favored low track,
though.
Temperatures likely warmer along the International Border with fewer
clouds, generally in the mid to upper 70s. Later Saturday evening,
another surface low will begin to dig southeastwards, which could
spark additional scattered showers and thunderstorms along the
International Border that will begin to dissipate into the overnight
hours. Higher dewpoints across the region will likely keep overnight
lows in the upper 50s to mid 60s.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
As of 350 PM EDT Friday...On Sunday there looks to be enough moisture
(1.50"PW), instability 500-1000 J/kg & 50 TT), and lift(weak sfc
convergence) for a little bit higher chance of thunderstorms as the
upper low slowly sags southward toward our region. However wind
profiles indicate weakening winds through the day as the upper low
nears such that below 6Kft it`s 10kts or less and only 20-25kt up at
20-39K ft, so shear is very weak. Expecting a wider coverage of
precipitation due in the instability resulting in 60-70% PoP
but chance of any organized severe thunder is low with the lack
of shear. Looking for highs in the mid 70s to lower 80s.
Sunday night things will settle down as we lose daytime heating so
precipitation threat wanes after sunset. The upper low keeps sliding
south overnight centered atop the area by Monday morning. Expecting
partly cloudy skies overnight with lows in the mid 50s to mid 60s.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 350 PM EDT Friday...We will be dealing with the upper low in
the vicinity for much of the long term with some chance for
showers/tstms and temps near normal at least through Wed before the
low drifts south or east by Thu/Fri depending on the model.
Mon-Wed with the center of the upper low and its associated cold
pool aloft lingering in the vicinity there will be daily chance of
showers/slight chance of thunder mainly in the afternoon and evening
hours. Wed-Fri trend a bit warmer and drier as the upper low drifts
away. Temperatures will be near seasonal norms, with highs in the
upper 70s/mid 80s warming into the 80s later in the week and
overnight lows in the upper 50s/mid 60s.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
Through 00Z Sunday...VFR conditions at all TAF sites through
the period. Overcast skies this evening will trend scattered by
tomorrow afternoon. Light and variable winds overnight will turn
out of the south/southwest tomorrow morning ahead of an
approaching weather system. Bulk of precipitation will remain
south of the region, but have included mention of VCSH at KMPV &
KRUT towards 16z tomorrow. Northern terminals should remain
mostly dry.
Outlook...
Saturday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.
Sunday: Mainly VFR, with local IFR possible. Chance SHRA, Chance
TSRA.
Sunday Night: Mainly VFR, with local MVFR possible. Slight chance
SHRA, Slight chance TSRA.
Monday: Mainly VFR, with local IFR possible. Chance SHRA, Slight
chance TSRA.
Monday Night: Mainly VFR, with areas MVFR possible. Slight chance
SHRA.
Tuesday: Mainly MVFR, with local IFR possible. Chance SHRA,
Slight chance TSRA.
Tuesday Night: Mainly MVFR, with local IFR possible. Slight
chance SHRA.
Wednesday: Mainly MVFR, with areas VFR possible. Chance SHRA,
Slight chance TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Haynes
NEAR TERM...Haynes/Taber
SHORT TERM...Sisson
LONG TERM...Sisson
AVIATION...LaRocca
Area Forecast Discussion
National Weather Service Caribou ME
1143 PM EDT Fri Jun 26 2020
.SYNOPSIS...
An upper low will move slowly south across the region with a
series of disturbances this weekend into early next week. High
pressure approaches the region late next week.
&&
.NEAR TERM /THROUGH SATURDAY/...
1130 pm update: Quick update to keep some showers around across
central and interior Downeast locations early tonight. A weak
shortwave is now crossing the region, tapping into remaining
elevated instability across the eastern half of the CWA. One or
two rumbles of thunder will be possible, but remains unlikely
through the predawn hours.
Previous discussion:
Activity will weaken and wind down after 9 PM w/the best
forcing pushing e. The RAP keeps some precip along eastern
Washington Co a bit longer into late evening(near midnight).
Will need to expand the precip chances a while loner to cover
this potential. Temps will cool down into the 50s w/some fog
expected overnight, especially along the coast and in areas that
received rainfall. A Beach Hazard Statement remains in effect
for the coast until 9 PM. Another item to note is that Caribou
reached 80F. This sets a record for the 11th consecutive day
with a high temperature of 80 degrees or warmer in Caribou.
Another upper level disturbance w/a sfc trof is forecast to
slide across the region on Saturday, while a weak sfc low is
shown by the 12Z NAM and GFS to move out of NYS and across
southern New England. Both set of guidance show two areas of
rainfall w/one area moving across northern areas. The
instability looks to be highest across northern and northwest
Maine during the afternoon. CAPE values of no more than 600
joules. Shear appears to be weak and lapse rates are marginal.
Decided to leave the mention of tstms in the forecast, but
expectation for anything strong is low. The system to the s
gracing the coast w/the best convergence and forcing remain to
the s. Decided to add slight chance for showers along the coast.
Daytime temps will be a tad cooler than they have been, but
comfortable.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
Saturday night the forecast area will remain south of the 500
MB low centered across Eastern Quebec province. This keeps the
forecast area in a west flow aloft. A pair of short waves, one
across the crown of Maine, and another to our south, cross the
region overnight. Much of the region remains dry Saturday night,
but there will be the chance of showers, mainly across the
north Saturday evening.
Sunday through Monday, the 500 MB low across eastern Quebec
drops southwestward across northern New England and then remains
through Sunday night. This pattern keeps the weather unsettled
through the period. Expect the chance for showers and
thunderstorms Sunday and the chance for showers Sunday night.
The upper low continues to meander across or just to our west on
Monday. This keeps the continued chance for showers across the
region.
Temperatures this period will actually average a bit below
normal for a change, after our string of above normal
temperatures.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
The 500 MB low will be the dominant weather feature through mid
week. Unsettled weather is expected right through mid week. For now,
have kept chances for showers and mainly isolated afternoon
thunderstorms through the mid week period, although it certainly
will not be raining all the time. Drier weather will return
toward the end of the week as temperatures start to once again
rise to above normal levels by the end of the week.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: Generally VFR into Saturday w/a period of MVFR and
perhaps IFR in patchy low clouds/fog at BHB and BGR late
tonight. VFR Saturday, but with brief MVFR possible in any
afternoon showers.
SHORT TERM: VFR expected most of the period, although periods
of MVFR are possible in any showers through the period.
&&
.MARINE...
NEAR TERM: The wind and seas will remain well below small craft
advisory levels into Saturday. Fog will be nuisance to mariners
once again overnight into Sat morning.
SHORT TERM: Winds/seas will be below SCA levels through the
period.
&&
.CLIMATE...
Today, June 26, 2020, marked the 11th consecutive day with a high
of 80 degrees (F) or warmer in Caribou, Maine. This breaks the
record for the most consecutive days with a high of 80 degrees or
warmer in Caribou. The old record of 10 days was from August
14-23, 2015. Weather records in Caribou date back to 1939.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...Beach Hazards Statement from 7 AM EDT Saturday through
Saturday evening for MEZ029-030.
MARINE...None.
&&
$$
Near Term...Cornwell/Hewitt
Short Term...Duda
Long Term...Duda
Aviation...Cornwell/Hewitt/Duda
Marine...Cornwell/Hewitt/Duda
Climate...CB
Area Forecast Discussion
National Weather Service Cheyenne WY
848 PM MDT Fri Jun 26 2020
.UPDATE...
Issued at 840 PM MDT Fri Jun 26 2020
It was another busy afternoon for strong to severe thunderstorms.
The focus for severe weather shifted south along the I-80 corridor
in southeast WY. A long track supercell produced a swath of large
hail (1 to 1.75 inch diameter) from Federal across north and east
Cheyenne to Carpenter WY. Other severe storms developed over
northeast CO. Convective coverage/intensity trends that past few
hours have been decreasing. Remnants of earlier convection lingered
along the WY-CO border, with redevelopment over parts of Carbon
and Albany counties. Lowered PoPs to match radar and HRRR trends.
Updates sent.
&&
.SHORT TERM...(This evening through Sunday night)
Issued at 135 PM MDT Fri Jun 26 2020
Tonight...The Storm Prediction Center outlook for marginal to slight
risk across our southeastern counties looks good through early
evening based on instability and shear parameters as well as the
HRRR prognosis. Though, the strongest storm development will likely
be across Colorado where better shear will exist. Will maintain a
chance of thunderstorms through this evening, with the greatest
chances across the southern Nebraska Panhandle.
Saturday...Thunderstorm chances should decrease as mid level
temperatures warm, leading to a stronger cap and limiting
thunderstorm chances. Still though, will forecast isolated
thunderstorms in the afternoon south of a Laramie to Alliance line.
Warmer temperatures as the 700 mb temperatures rise to near
14 Celsius.
Saturday night...Even more mild than tonight as the airmass
continues to warm.
Sunday/Sunday night...The flow aloft turns southwest and with enough
mid level moisture and strong daytime heating along a surface
trough, expect isolated to widely scattered afternoon and evening
thunderstorms focused mainly across southeast Wyoming. Even warmer
temperatures on tap with 700 mb temperatures near 15 Celsius. Even
warmer Sunday night as the airmass continues to modify.
.LONG TERM...(Monday through Friday)
Issued at 135 PM MDT Fri Jun 26 2020
Typical early summer weather expected over the cWa next week with
almost daily chances for afternoon and evening convection.
Activity will be aided by a slowly weakening upper trough that
will be over the northwestern part of the country. Most widespread
activity looks to occur Tuesday as a decent shortwave lifts
northeast across the region and pushes a cool front across the
CWA. Models in decent agreement with this scenario. Warming again
to close out the week with convection becoming more isolated.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday afternoon)
Issued at 535 PM MDT Fri Jun 26 2020
VFR. Wdly sctd SHRA/TSRA will continue through 03Z. Gusty/erratic
surface winds and MVFR VIS will accompany the stronger convection.
&&
.FIRE WEATHER...
Issued at 135 PM MDT Fri Jun 26 2020
Lower afternoon humidities Saturday through Monday will increase
concerns somewhat, then concerns will lessen Tuesday through
Wednesday as temperatures cool and humidities increase slightly.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
UPDATE...MAJ
SHORT TERM...RUBIN
LONG TERM...RE
AVIATION...MAJ
FIRE WEATHER...RUBIN
Area Forecast Discussion
National Weather Service Lincoln IL
807 PM CDT Fri Jun 26 2020
.SYNOPSIS...
Issued at 330 PM CDT Fri Jun 26 2020
Showers and thunderstorms, some possibly severe this evening, can
be expected in northern Illinois. This activity is expected to
weaken as it sinks southward into central Illinois tonight. A cold
front will become nearly stationary across north central Illinois
this weekend. This will result in periods of showers and
thunderstorms with warm and humid conditions through Sunday.
&&
.UPDATE...
Issued at 807 PM CDT Fri Jun 26 2020
Well defined MCS pushing through northeast Illinois and southern
Lake Michigan has begun to see trailing convection forming back
into southern Iowa, along a surface boundary. Evening sounding
from our office shows the cap largely eroded and surface based
CAPE`s around 2600 J/kg, with SPC mesoanalysis showing downdraft
CAPE`s just south of this line around 800-1000 J/kg. 18Z NAM-Nest
remains the model that seems to have the best handle on the
situation, though the HRRR is starting to jump on board. In this
scenario, the line of storms will continue to drop southward into
the northern CWA through late evening, before pushing to around
I-72 toward 3 am. No changes noted in the just-issued Day1
convective outlook, with the slight risk continuing from about
Macomb to Bloomington to Hoopeston northward.
Recent forecast updates were mainly to adjust the rain trends for
tonight and early Saturday.
&&
.SHORT TERM...(This evening through Saturday)
ISSUED AT 330 PM CDT Fri Jun 26 2020
Plenty of convective activity, mainly north of I-80 at 3 pm, will
eventually sink southward into north central and then central IL
later this evening. Many of the CAMs are much weaker with the
convection than what is actually occurring. However, the NAM nest
3km model seems to have a good handle on things so far. The main
forcing for the storms is an impressive Mesoscale Convective
Vortex (MCV)very close to LaCrosse, WI. The ESE movement of this
toward southern lower MI will be the main reason for the
weakening trend in the storms across our area. A strong storm or
two is still possible north of I-74 from GBG-PIA-BMI around 9-10
pm. The rest of central and east central IL can expect a period of
t-storms after midnight, with no precipitation expected in
southeast IL tonight.
On Saturday, various boundaries will provide the focusing
mechanism and a weak shortwave moving toward west central IL from
the west will provide the forcing to produce the likelihood of
showers and t-storms, particularly by late afternoon and into the
evening. A few of the storms could be strong just ahead of the
path of the shortwave.
.LONG TERM...(Saturday night through Friday)
ISSUED AT 330 PM CDT Fri Jun 26 2020
A very warm and humid pattern looks to be in store for the
forecast area much of next week. This will also result in periods
of showers and t-storms each day, mainly diurnally driven.
The main synoptic boundary is expected to take on a NW to SE
orientation across IL as upper ridging builds to the west on
Sunday. This will result in the higher rainfall chances from
central to SE IL, and into central KY.
With this boundary remaining nearly stationary across central and
SE IL much of the week, daily chances of showers and t-storms will
be present. However, many of the medium range models appear to be
overdone with the precipitation - especially since the upper flow
is expected to be quite weak with a ridge axis near us, resulting
in little in the way of forcing. Thus, trended more toward
diurnally driven, chance PoPs for Monday through Friday. High
temperatures will hover around 90, so with dew points in the upper
60s to lower 70s the daily heat index will be in the lower-mid
90s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 620 PM CDT Fri Jun 26 2020
All will be quiet the first couple hours of the TAF period, with
main concern being the development of thunderstorms that could
impact KPIA/KBMI initially. 23Z radar showing an increase in
storms over southeast Iowa, which will be on track for reaching
these two sites between 03-06Z. Evolution further south is more
uncertain, though a VCTS mention is warranted the rest of the
night. Have kept the mention of MVFR ceilings across eastern
Illinois early Saturday morning, with improvement in the early
afternoon. While scattered storms are still possible in the
morning, think the better chances will be in the afternoon and
will limit the additional VCTS mention to after 18Z.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SYNOPSIS...Miller
SHORT TERM...Miller
LONG TERM...Miller
AVIATION...Geelhart
Area Forecast Discussion
National Weather Service Marquette MI
740 PM EDT Fri Jun 26 2020
.SHORT TERM...(This evening through Saturday)
Issued at 157 PM EDT FRI JUN 26 2020
Low pressure moving east through Ontario with a cold front extending
south has inched closer this morning. Morning warm front lifting
through the region resulted in some light shower activity, mainly in
the west, parts of the Keweenaw and over central Lake Superior.
Behind this feature, skies have cleared some, although some high
clouds from last nights MCV in SE MN filtered into the area.
Additionally, dewpoints have climbed into the 60s across the area;
this coupled with temps in the 70s in most locations have resulted
in a muggier day.
This afternoon, daytime instability is still progged to increase
ahead of the approaching cold front in the west and central UP. CAPE
values among the guidance top out around 2500 j/kg. This instability
coupled with 0-6km shear of ~35kts should be enough to support
thunderstorm development this afternoon. Much of this will likely
depend on cloud cover and being able to realize this instability.
Guidance suggests activity to begin around 20z with a line of
scattered storms developing over the west and moving into the
central. Recent RAP and NAMNEST soundings show some curvature in the
lower levels of the hodographs, which alludes to some potential for
some rotating thunderstorms, but overall the flow is linear through
the column. SRH values are also considerably lower than yesterday`s
guidance, which now points to a much lower concern for tornadic
activity. The bigger hazard does still include damaging wind though,
particulary because of DCAPE values approaching 1000 coupled with
some strong low level lapse rates and drying at the mid levels.
Recent RAP soundings point to weak lapse rates above 700mb and
within the hail growth so the hail potential, while still there in
any organized updraft given the CAPE profile, is looking less
impressive than previous guidance runs. High PWATS still allude to
the potential for pockets of moderate to heavy rain being possible,
but given the speed at which these systems are progged to move
through the region and the lack of training on the back end, flash
flood threat is low. Overall the storms will move toward the ESE
toward Lake Michigan through the late afternoon and tonight as the
cold front advances east. As the sun sinks lower toward the horizon
and instability wanes, expect the convection to weaken.
Following this afternoon`s convective event, expect winds to shift W-
NW as high pressure builds in from the west. Skies will become clear
to partly cloudy and lows will drop into the mid to upper 50s.
Tomorrow, high pressure will continue building across the area,
resulting in some diurnal CU in the afternoon as daytime lapse
rates peak. Overall though, expecting `chamber of commerce
weather` with highs topping out near 80 in the interior and the
70s by the lakeshore.
.LONG TERM...(Saturday night through Friday)
Issued at 422 PM EDT FRI JUN 26 2020
The extended fcst will feature another blocking pattern developing
across the CONUS as upper-level ridging returns to the central U.S.
with two cutoff lows developing, one over the NE U.S and the other
over the western CONUS, later this weekend/early next week.
Operational models and ensembles suggest the prominent ridge
developing over the central CONUS and western Great Lakes could
persist through much of next week with a definite return of well
above normal temperatures and generally drier conditions. Inland
high temperatures by early next week will likely be well into the
80s, perhaps even lower 90s at a few locations, with min temps
generally in the upper 50s to lower 60s. If any locations across the
Upper Peninsula were to see showers/possible storms return, it would
most likely be over the far western Upper Mi late Sun night into
Tue, before the mid-upper level ridge reaches full strength, a few
shortwaves may lift up its backside through the Upper Mississippi
Valley/Northern Plains triggering convection.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 739 PM EDT FRI JUN 26 2020
VFR conditions are expected through the forecast period.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 157 PM EDT FRI JUN 26 2020
Cold front will move west to east across the lake this afternoon and
evening. Before the frontal passage, expect SW winds in the west to
SE in the east at around 10-15kts at the surface with some higher
sustained winds above 20kts being possible at the some of the higher
platforms. As the front moves through, expect scattered showers and
thunderstorm development, mainly in the central portions of the lake
late this afternoon and into the east by evening. Some storms could
be strong with high winds, frequent lightning and some hail being
possible. Following the frontal passage tonight, expect winds to
shift northwest as high pressure builds into the area. Some fog may
be possible, especially if moderate to heavy rain does occur this
afternoon/evening. This high will linger into next week, keeping
winds calm through the remainder of the forecast period.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JP
LONG TERM...Voss
AVIATION...TAP
MARINE...JP
Area Forecast Discussion
National Weather Service Nashville TN
709 PM CDT Fri Jun 26 2020
.UPDATE...
FOR EVENING DISCUSSION.
&&
.DISCUSSION...
A surface high is centered over Alabama this evening with a weak
upper ridge covering Middle Tennessee. However, a shortwave
developing to our west will provide the impetus for increased
precipitation coverage this weekend. At this time, isolated
showers are still showing up on radar, but they should be gone by
maybe 02Z. So we`ve extended slight chance POP`s into the early
evening to account for the lingering activity. There are plenty of
clouds covering the mid state this evening, so it is difficult to
discern just how much of the dust has filtered into Middle
Tennessee. There maybe some dust mixed in with the clouds, but
everything we`re seeing on satellite is mainly just clouds. Will
likely make some adjustments to the hourly grids to account for
the increased cloud cover this evening. No other changes are
planned for now.
&&
.AVIATION...
00Z TAF DISCUSSION.
BNA/MQY/CKV/CSV...Isolated showers are still showing up on radar
as we head into the evening. The latest HRRR suggests that these
will entirely dissipate by about 03Z, but then regenerate starting
around 10Z. Will leave the terminals dry for now but will keep an
eye out should one of these cells get close. Will handle
tomorrow`s rain chances with VCSH remarks for now, except VCTS for
CSV during the afternoon. Likelihood of fog appears low as winds
should stay up a few knots overnight.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION......08
AVIATION........08
Area Forecast Discussion
National Weather Service Spokane WA
623 PM PDT Fri Jun 26 2020
.SYNOPSIS...
A strong cold front will track through the Inland Northwest
tonight into early Friday and will bring much cooler temperatures,
windy conditions and a chance of showers and afternoon
thunderstorms on Saturday. Much cooler and wetter weather will
persist into early next week. Subtle drying and warming is
expected by mid-week.
&&
.DISCUSSION...
Evening update: A strong cold front is moving into Central WA this
evening and will reach Eastern WA and N Idaho during the late
evening and overnight hours. Made an update mainly to the evening
POP`s where latest model data is keeping the main shower threat
near the Canadian border. Also adjusted sky cover based on current
satellite trends. The latest HRRR runs indicate some sprinkles
possibly reaching the ground with the front in Central WA but with
current temperature- dew point spreads of 35-45F even this is
doubtful. And with current satellite trends showing a stable
orographic cirrus in the lee of the Cascades in combination with
downslope flow off the Cascades this further supports a dry
forecast for Central WA. As the front moves east tonight models
are generating little in the way of precipitation, with the
Central Panhandle Mountains having the highest threat where the
strength of the front combined with upslope flow may be just
enough for light precipitation. JW
&&
.AVIATION...
00z TAFS: VFR conditions expected at all TAF sites through 00z
Sunday. A cold front passage will deliver breezy winds this
evening into the overnight with gusty winds persisting behind the
front into Saturday. The front will also bring a period of
increasing cloud cover as well as a small chance of showers after
06z. Not confident any of these will impact any of the TAF sites,
however if any did COE would be the closest to them. JW
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 61 77 49 67 53 70 / 20 0 20 60 60 60
Coeur d`Alene 60 75 48 67 53 67 / 30 10 20 60 70 70
Pullman 60 74 47 62 49 64 / 20 10 10 40 70 80
Lewiston 68 83 55 68 55 69 / 10 10 10 50 80 80
Colville 56 80 48 72 51 78 / 20 20 40 80 50 40
Sandpoint 59 76 49 68 54 69 / 30 10 40 80 80 70
Kellogg 61 73 49 64 52 62 / 30 20 20 70 90 80
Moses Lake 61 84 52 74 56 83 / 10 0 10 50 40 40
Wenatchee 62 79 54 73 57 82 / 10 0 10 50 30 20
Omak 58 81 52 73 57 82 / 10 10 10 70 40 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Paducah KY
932 PM CDT Fri Jun 26 2020
.UPDATE...
Issued at 932 PM CDT Fri Jun 26 2020
The Lake Wind Advisory has been allowed to expire as scheduled at
9 PM. Winds will hover around 10 mph for most of the night, so
increased lows just a bit in a few places. What little convective
activity there was over southeast Missouri went away by sunset,
so have removed that mention from the HWO along with the Lake Wind
Advisory. The HRRR and 00Z NAM support the increasing PoPs after
09Z tonight from the Bootheel into the Purchase Area, so left that
alone.
&&
.SHORT TERM...(Tonight through Sunday night)
Issued at 245 PM CDT Fri Jun 26 2020
We will continue with a slight chance of showers/storm moving
across the TN/AR borders into SEMO and west KY through the end of
the day. Most of tonight should be dry. Late in the night we may
see some activity redevelop over the southern part of the area.
Chances will continue Saturday. After that, best chance PoPs and
slightly better QPF will shift to the east 1/2 of the area and
peak Saturday night into Sunday as a s/wv ridge tries to push over
the region from the west. Very warm and humid conditions now in
place as we have advected in 70 dew point air upon moist return
flow. Cannot rule out a strong storm and locally heavy rain.
Overall, not that concerned.
.LONG TERM...(Monday through Friday)
Issued at 245 PM CDT Fri Jun 26 2020
A blocking pattern in the middle of the country, flanked on both
sides by closed lows, will be the primary synoptic feature in the
long term. The Quad State region will be right of center of the
blocking ridge axis. A trailing cold front from the eastern closed
low will stretch across to the north of the forecast area at the
start of the long term. The front will provide a focal point for
smaller scale vorticity elements and convection. As such, the
highest chances of showers and storms Monday will be towards the
Evansville Tri-State while Southeast Missouri will have lower
chances. Storm activity during the long term will be primarily
diurnally driven, so afternoon hours are the most likely for
thunderstorms.
Through the rest of the long term forecast, the closed low to the
east will slowly drift southward. This will bring the cold front in
the midwest very slowly southward as well, turning nearly stationary
at times. Complicating matters is the development of a surface low
in the lee of the Colorado Rockies Tuesday. There seems to be a bit
more alignment this cycle of the GFS with the ECMWF in terms of
slowly drifting this low eastward. With this surface low, southerly
flow from the Gulf, and the nearly stationary front across the
midwest near the ridge/trough boundary, showers and storms will be
possible through the rest of the long term. As the front slowly
drifts southward across the forecast area, the higher precipitation
chances will similarly shift towards Western Kentucky and Southeast
Missouri while the Evansville Tri-State will see decreasing
probabilities.
In the latter portion of the forecast period, the closed low in the
west will lift northward around the ridge towards Canada. The ridge
will then build back into the west. This could allow for the eastern
trough to also build back into the Quad State, though this
possibility is comparatively less certain.
Highs near 90 at the start of the long term will shift downward as
the front drifts southward. Timing of the front is uncertain; it is
likely that when it is across the Quad State, the north-south
temperature gradient will be larger than what is forecast. Southerly
flow will keep dew points near 70 and lows in the lower 70s
throughout the long term though some amount of dropoff is
anticipated on the north side of the front.
&&
.AVIATION...
Issued at 550 PM CDT Fri Jun 26 2020
Moist southwest winds will increase the potential for low clouds and
showers/thunderstorms by early Saturday morning. Winds will remain
on the gusty side through the night, gusting around 15 kt. Areas of
mvfr cigs are likely to arrive toward sunrise, accompanied by some
shower or thunderstorm activity. The activity is forecast mainly
east of the Mississippi River. It appears any storms will become
more isolated in the afternoon, so no mention of storms is included
after 19z. Cloud bases will rise to vfr levels. Winds will remain
gusty.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...DRS
Area Forecast Discussion
National Weather Service Tallahassee FL
1047 PM EDT Fri Jun 26 2020
.UPDATE...
Rain chances are winding down for the night. Skies will remain
mostly cloudy overnight. Low temperatures will fall into the low
70s.
&&
.PREV DISCUSSION [637 PM EDT]...
.NEAR TERM [Through Tonight]...
Interesting forecast through this evening as temperatures are
several degrees below forecast in spots. Suspect less solar
radiation is making to the surface based on the combination of
dust and high level clouds. This appears to be having an impact
on our chances for convection, with the relative absence of
more robust cumulus fields. Noting some of the high resolution
guidance such as the HRRR continues to trend downward in terms
of precip, while the sea-breeze circulation that would be the
primary triggering mechanism is also less robust than expected,
due to the weaker land-sea temperature differential. We also
noted a 2C mid-level cap on the 12Z TAE sounding that models
are resolving poorly. Overall, we have decreased the chance of
precipitation to slight through this evening, which includes
thunder as well. Overnight, benign weather is expected.
A similar pattern will be in place on Saturday with deep layer
ridging and a light southwest flow centered at 850 hPa. Given a
similar atmospheric profile compared to today, expect continued
high cloudiness and haze. Based on the pattern, have went a few
degrees below guidance for high temperatures, but still low to
mid 90s expected across much of the area. Heat indices could
near 105 degrees in spots. Chances for precipitation will again
be limited to ~25 percent with any showers or thunderstorms
that are able to develop in the late afternoon and evening.
This potential may be greatest in the far northwest where an
isolated strong wind gust is possible given steeper lapse rates
and a slightly stronger wind field, although instability looks
limited.
.SHORT TERM [Saturday Night Through Sunday Night]...
Mostly dry conditions are on tap for the remainder of the weekend as
ridging prevails over the eastern US with surface high pressure
settled over our area. There is a low-end chance for showers/storms
Sun afternoon from a weak seabreeze convergence boundary, but
coverage is expected to be limited. Although little to no rain is
forecast, the possible presence of lingering Saharan dust in the air
would lead to hazy/overcast skies. This factor may keep daytime high
temperatures in the low (instead of mid) 90s. Minimum temperatures
will stay quite warm (low 70s).
.LONG TERM [Monday Through Friday]...
An interesting synoptic pattern unfolds throughout the long-term
period as a large mid/upper, east Canadian low cuts off and moves
south along the mid-Atlantic states. The aforementioned ridging
breaks down as troughing takes hold of the eastern US. A backdoor
front is forecast to develop at the surface and usher in some cooler
air from the north and provide lift in conjunction with daytime
heating for scattered showers and thunderstorms. The GFS and ECMWF
appear to be in reasonable agreement on this scenario. However, the
NBM is aggressive on PoPs at Days 6-8. Although a wet pattern is
anticipated, highest rain chances on the back end of the period were
reduced to 50-55% range as it is still too early to be this
confident in precipitation. High temperatures are expected to be
mostly in the low 90s, with portions of southeast AL and southwest
GA possibly seeing upper 80s. Low temperatures will be in the low
70s.
.AVIATION...
[Through 00Z Sunday]
Brief MVFR is possible at times through the TAF period in DU/HZ,
with low confidence on timing and location. Vicinity thunder at
DHN, ECP, and VLD will dissipate by 01Z. A PROB30 for TSRA is in
effect 20-24Z for for DHN, TLH, and VLD. Light southeast winds
tonight veer to the southwest on Saturday, mainly AOB 5 knots.
.MARINE...
Outside of showers and thunderstorms, favorable boating conditions
prevail through the period with west-to-southwest winds of 10
knots or less and 1-2 ft seas.
.FIRE WEATHER...
High dispersions are likely through this weekend. Outside of the
high dispersions, hazardous fire weather conditions are not
expected.
.HYDROLOGY...
Dry conditions are forecast for much of the weekend, before a wet
pattern returns around mid-week. However, 7-Day rainfall
accumulations are expected to generally be about 1 inch, with
isolated areas possibly seeing higher amounts. All local rivers and
creek are also in good shape. There are no flood concerns at this
time.
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur (while following all local, state, and CDC guidelines) by
calling the office or tweeting us @NWSTallahassee.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 73 94 74 96 73 / 20 20 0 20 0
Panama City 76 90 77 91 77 / 10 10 0 10 0
Dothan 71 90 73 94 72 / 20 30 0 20 0
Albany 73 93 74 95 73 / 20 20 10 20 10
Valdosta 73 92 73 94 72 / 20 30 10 20 0
Cross City 74 95 73 95 73 / 10 20 0 10 0
Apalachicola 76 87 76 89 76 / 0 10 0 10 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk until 11 PM CDT this evening for South
Walton.
GA...None.
AL...None.
GM...None.
&&
$$
UPDATE...Scholl
NEAR TERM...LF
SHORT TERM...IG3
LONG TERM...IG3
AVIATION...LF
MARINE...IG3
FIRE WEATHER...LF
HYDROLOGY...IG3