Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/22/22
Area Forecast Discussion
National Weather Service Cleveland OH
926 PM EDT Tue Jun 21 2022
.SYNOPSIS...
A ridge of high pressure will weaken tonight allowing a cold
front to sink across the region Wednesday. High pressure will
build in behind this front Wednesday night and remain in control
through the start of the weekend.
&&
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
Update...
Forecast remains on track. No changes appeared necessary late this
evening. Latest hi-res model guidance continues to suggest minimal
potential for showers and thunderstorms to accompany the cold front
as it approaches from the northwest and nears the major axis of Lake
Erie and our far-northwestern OH counties around daybreak tomorrow
morning. It appears a lack of stronger low-level convergence along
the front and moderate to excessive boundary layer CIN, including
surface-based CIN, should prevent convection initiation despite the
expectation for MUCAPE to build to moderate to strong magnitudes
overnight tonight as low-level WAA and moisture advection occur in
the warm sector.
Previous Discussion...
The main story late this afternoon through tonight is the heat
and increasing humidity as an expansive mid/upper ridge remains
anchored over the TN Valley. H5 heights in the center are
595-597 DM over the TN Valley, with H5 heights of 591-594 DM
extending north across the lower Great Lakes. These heights,
along with 850 mb temps averaging 20-21 C across the region and
full sunshine due to the strong subsidence beneath the ridge,
have allowed temps to warm into the upper 90s in NW Ohio, mid
90s in north central and NE Ohio, and upper 80s in NW PA.
Visible satellite loops do not show any cumulus development, and
this is due to both a strong mid-level cap analyzed in the
latest RAP forecast soundings and CAPE values limited by dew
points only in the 55-60 range. A mid/upper shortwave trough,
currently located over North Dakota, will progress into the
Upper Great Lakes tonight and begin to flatten the ridge. This
trough will be weakening as it runs into the strong ridging, and
the associated surface low will pass well north into Hudson
Bay. This will lead to a weak cold front settling south through
the Midwest and central Great Lakes tonight. Increasing
warm/moist advection ahead of the boundary will finally bring
dew points up into the 65-70 range tonight, and this along with
the hot antecedent conditions will hold lows in the low/mid 70s
leading to a warm, muggy night.
The aforementioned cold front looks to cross Wednesday morning into
early afternoon. This early timing, along with limited shear and
upper forcing displaced so far north, will keep any isolated severe
convection confined to far southern areas Wednesday afternoon from
about Mt Vernon to Marion. A few showers and isolated thunder will
develop along the frontal boundary over the lakeshore counties
Wednesday morning, before pushing inland during the early afternoon,
but the limited forcing will lead to isolated to only widely
scattered coverage. HREF CAMS have caught onto this thought process
and now generally show new convective development south and
southeast of our CWA Wednesday afternoon, so it`s possible that we
don`t see any severe weather at all. However, MLCAPE is progged to
exceed 3000 J/Kg by early afternoon with over 4500 J/Kg of SBCAPE,
and steep low-level lapse rates of 8.5 to 9 C/Km, dry mid-levels
characterized by RH below 60%, and DCAPE of 1050-1200 J/Kg all could
lead to isolated severe downburst/wet microburst pulse type
convection. For this reason, the latest SWODY2 keeps a marginal risk
from a line just north of Meadville to north of Mansfield. Any
thunderstorm will also contain locally heavy rain since mean winds
in the mid-levels will only be around 17 knots leading to slow storm
motions of 10 knots or less, and this combined with seasonably high
PWATs of 1.7 to 2.0 inches, deep warm cloud depths, and relatively
skinny CAPE profiles all support localized torrential rainfall. The
best chance for this will again be in far southern areas. Highs
Wednesday will warm into the upper 80s to mid 90s (highest in NW
Ohio), but greater cloud cover will keep heat indices below criteria.
Any showers/storms will exit quickly Wednesday evening leading to
dry conditions Wednesday night as mid/upper troughing skirts across
the Great Lakes and surface high pressure builds in from the Upper
Midwest/western Great Lakes. This will allow cooler, drier air to
filter into the region, so lows will drop into the upper 50s to mid
60s.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
An upper level ridge building east over the area during this
forecast period should continue to bring fair weather to the
forecast area. The upper level ridge will result in surface high
pressure that is expected to remain nearly stationary Thursday
through Friday night over the forecast area. Although, a weak
surface trough is expected to move southeast across the region
Wednesday night. The cold air advection in advance of the surface
high pressure should keep temperatures in the middle to upper 70s
across the east and lower to middle 80s in the west Thursday. Light
winds by Thursday night will allow for radiational cooling to take
place and drop lows into the 50s east and around 60 west. Subsidence
takes place Friday allowing temperatures to jump back into the
middle and upper 80s for highs by Friday and lows Friday night into
the upper 50s east to middle 60s west.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
An upper level ridge shifts east of the area during this period
forcing the surface high to move east off the New England Coast
by the weekend. A return southerly flow develops and with it
warm air advection heading into the weekend. Models suggest an
upper level trough should move east across central Ontario,
Canada by Sunday forcing a weak area of low pressure to move
east as well. The low will force a cold front east across the
forecast area Sunday along with a swath of moisture. Instability
and warming ahead of the cold front should support a threat for
showers/thunderstorms across the area with the frontal passage.
Cold air advection follows the cold front Sunday night into
Monday. Another weak upper level ridge is progged to move east
into the area Monday night into Tuesday forcing a surface high
to build east across the area. QPF amounts look to be rather
light with the cold frontal passage at this time. Otherwise,
expect warming to take place Saturday through Sunday followed by
cooler temperatures into early next week.
&&
.AVIATION /00Z Wednesday THROUGH Sunday/...
A surface cold front should sweep southeastward across our
region between ~12Z and ~18Z/Wed and will be flanked by surface
high pressure. Southwesterly regional surface winds around 5 to
15 knots veer to northwesterly following the front`s passage.
Primarily VFR are expected through the period. However, isolated
showers and thunderstorms are possible along and in vicinity of
the front, especially south of the latitude of KMFD and between
~15Z and ~21Z/Wed. This convection may be accompanied by brief
MVFR to LIFR in heavy rainfall and brief/erratic surface gusts
up to 50 knots.
Outlook...Non-VFR possible in isolated showers and thunderstorms
Wednesday evening and again on Sunday.
&&
.MARINE...
Westerly flow should become more northerly by Wednesday afternoon as
a cold front moves across the area Wednesday. Northerly flow will
persist into Thursday and then become light and variable by Friday
as high pressure builds east across the area. The high pushes east
of the area over the weekend and a return southerly flow, albeit
light, develops by Saturday. Winds should increase Saturday night
into Sunday as a cold front sweeps east across the lake.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.
&&
$$
SYNOPSIS...Garuckas
NEAR TERM...Garuckas/Jaszka
SHORT TERM...Lombardy
LONG TERM...Lombardy
AVIATION...Jaszka
MARINE...Lombardy
Area Forecast Discussion
National Weather Service State College PA
1055 PM EDT Tue Jun 21 2022
.SYNOPSIS...
Summertime heat and humidity arriving on schedule will increase
into midweek, fueling a risk of severe thunderstorms and
flooding downpours on Wednesday. Showers could linger over
eastern Pennsylvania early Thursday, but the overall
precipitation trend will be drying out with lower humidity for
late week. The last weekend of June 2022 should start off dry
before showers and thunderstorms likely return on Sunday.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Satellite imagery this evening is showing mainly clear skies
across central Pa in region of upper level ridging and low
pwats. Some model guidance indicates the chance of late night
showers associated with a weak shortwave cresting the ridge and
the return of higher pwats. However, a lack of upstream
convection over southern Ontario, as well as the latest HRRR and
12Z HREF, suggest dry weather is likely overnight.
Low temperatures should range from the mid to upper 60s over
much of the forecast area. However, min temps closer to 60F
appear likely over the eastern edge of the forecast area on the
cool side of a stalled warm front.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Wednesday continues to shape up to be a potentially active wx
day across CPA with both WPC and SPC upgrading the ERO and SWO
categorical risk levels from MRGL to SLGT.
Falling heights ahead of a shortwave diving through the Grt Lks,
combined with heating of moist/unstable air mass over western
and central Pa, should result in developing convection during
the afternoon. In general, model soundings are pointing toward a
high cape/low shear environment, supportive of isolated severe
weather during the PM hours. However, increased shear in
vicinity of a stalled warm front should support more sustained
updrafts and a correspondingly greater threat of severe weather
in that area. There is some model spread/forecast uncertainty
where this north/south boundary will be, but ensemble mean
suggests it will run from Potter or Tioga Co in the north, to
Fulton or Franklin in the south. A cooler, more stable air mass
east of the front should result in a diminished threat of severe
weather in that part of the state.
An environment of high CAPE in excess of 2000 J/kg, combined
with high pwats of around +2SD above climo, could also result
in locally excessive rainfall and flooding. Latest FFG is fairly
high, but convection-allowing models indicate spot amounts of
3-4 inches are possible in the vicinity of the stalled front,
so flash flooding is possible in this area.
MaxTs Wednesday should range from around 80F over the eastern
edge of the forecast area on the cool side of the front, to near
90F in the deeper valleys across the western half of the state.
Expect dwindling convection Wednesday night, as backdoor cold
front pushes through the western counties. However, passage of
mid level shortwave will keep the chance of showers going,
especially over the eastern counties, where the deepest moisture
will lie. In between any showers model soundings support patchy
drizzle due to an upsloping southeast flow and a nearly
saturated 0-1km layer.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Model soundings still support morning stratus and patchy drizzle
over much of the forecast area Thursday. Hoever, large scale
subsidence behind exiting shortwave should bring brightening
skies by afternoon.
All guidance supports fair weather Friday and Saturday, as
surface high builds east into the region. Model 850mb temps
support seasonable temperatures Friday, then a warmer return
southwest flow is likely Saturday, as surface high slips off the
east coast.
Heat and humidity notch up Sunday ahead of an approaching cold
front, which should be accompanied by a good chance of
convection Sunday PM based on latest ensemble plumes. Lingering
convection is possible Monday (mainly southeast Pa), depending
on timing of the front. Medium range guidance then supports a
fairly high confidence of fair and cool conditions Monday night
into Tuesday associated with the arrival of high pressure.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
A north/south oriented front remains nearly stationary across
central PA tonight. Low level moisture is limited on the west
side of the front, and slightly higher to the east. Most
locations will be VFR tonight, but some vsby restrictions in
BR/FG can`t be ruled out in the lower Susq late tonight.
For Wednesday, numerous showers and some thunderstorms look
likely for at least a portion of central PA. Rain looks most
likely at UNV, closest to the N-S oriented boundary. Some low
clouds and vsby restrictions will be possible Wed evening on the
east side of the front.
Outlook...
Thu...Mainly VFR. Isolated SHRA SE.
Fri-Sat...Mainly VFR.
Sun...Mainly VFR. Chance of a shower or storm, mainly late.
&&
.CLIMATE...
Astronomical summer (solstice) begins at 5:14 A.M. EDT today.
The summer season duration is 93 days, 15 hours, and 50 minutes
before the Fall Equinox on September 22, 2022 at 9:04 P.M.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...DeVoir/Steinbugl
NEAR TERM...Fitzgerald
SHORT TERM...Fitzgerald/Steinbugl
LONG TERM...Fitzgerald/Dangelo
AVIATION...Martin/Colbert
CLIMATE...
Area Forecast Discussion
National Weather Service Dodge City KS
1045 PM CDT Tue Jun 21 2022
...Updated Aviation...
.SHORT TERM...(This evening through Wednesday)
Issued at 400 PM CDT Tue Jun 21 2022
This afternoon`s water vapor loop and RAP analysis showed that the
North American Monsoon circulation was well-established, extending
from northern Mexico through southeastern Arizona and much of New
Mexico...up northeast through eastern Colorado and adjacent western
Kansas. At the surface, a weak front pushed and became stationary
between Dodge City and Garden City. Thunderstorms developed mid
afternoon in vicinity of the frontal zone once convective
temperature was reached. Thunderstorms will be sub-severe for the
most part, although we will need to watch the eastern counties where
SBCAPE is a bit higher, although even across the eastern counties
the CAPE isn`t all that high. Much better low level moisture was
across central and south central KS. We will maintain some 40-50
POPs across much of the southwest Kansas region, with Likely POPs up
around Hays, closer to the better low level moisture later tonight.
The front will make another push south tonight and eventually stall
out again on Wednesday farther south than this afternoon`s position.
Post-frontal easterly upslope flow will draw in better low level
moisture across southwest Kansas, setting the stage for a better
thunderstorm opportunity across our region.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 400 PM CDT Tue Jun 21 2022
Thursday and Friday will be the hottest days of the Long Term period
ahead of the next strong cold front due in later Saturday. Friday
may very well be the hottest day of the young summer season so far
for much of southwest Kansas with widespread high temperatures of
103 to 106 likely. As mentioned by the previous shift, it would not
be too surprising if Dodge City topped 105F if the best downslope
momentum plume noses northeast right across Dodge. Timing of the
cold front on Saturday will present a temperature forecasting
challenge, as frontal passage will most likely occur earlier in the
day than previous forecast. The official high temperature for
Saturday at DDC is 93, but this may need to be lowered if the
forecast front timing continues to be earlier in the morning. An
anomalously cool airmass by late June standards will drive south
across the Central Plains, supporting much cooler surface
temperatures Sunday. The latest NBM guidance came in this afternoon
with a high of only 78F at Dodge City for Sunday. Much like today
and tomorrow, the monsoon circulation will become infused with the
weekend frontal system, leading to another good chance for rain
across our region. The NBM POPs have been increased to 40-50 percent
across much of southwestern Kansas given the greater agreement among
global spectral models and their ensemble members. The cool airmass
will continue through early next week before slowly modifying by
around Tuesday of next week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1045 PM CDT Tue Jun 21 2022
Midlevel cloud decks will persist for most of this TAF cycle, with
a plume of monsoonal subtropical moisture spreading over SW KS.
Ceilings will average in the 9-12k ft AGL range. Scattered rain
showers may redevelop as early as Wednesday morning, but have
higher confidence of another round of scattered thunderstorms
after 18z Wed. Much like yesterday, confidence of direct
convective impacts at any terminal is low, so again only included
a VCTS/CB mention for now. Winds will be light this TAF cycle,
with light north winds currently, gradually trending SEly
Wednesday afternoon. Winds are expected to remain generally less
than 10 kts.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 88 66 98 / 70 40 30 10
GCK 65 87 65 98 / 30 40 30 10
EHA 62 88 64 96 / 30 40 30 10
LBL 66 90 65 98 / 30 30 30 0
HYS 67 85 67 95 / 30 30 30 30
P28 70 91 70 98 / 30 30 20 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Umscheid
AVIATION...Turner
Area Forecast Discussion
National Weather Service Goodland KS
506 PM MDT Tue Jun 21 2022
.SHORT TERM...(This evening through Thursday)
Issued at 327 PM MDT Tue Jun 21 2022
At the beginning of the short term period, the latest RAP analysis
shows the CWA with a southwesterly flow aloft being between a
positively tilted trough in the west and a positively tilted ridge
in the east. Current satellite imagery shows a good amount of cloud
cover over the entire CWA with radar data showing hit or miss light
rain showers going across the CWA from Cheyenne Wells up northeast
through McCook and beyond. Forecast guidance continues to depict the
southwesterly flow over the CWA throughout the day with an upper air
high starting to move over OK/TX. At the surface, spotty light rain
showers look to be possible particularly in the along and east of
the area line mentioned previously. Convective parameters for the
remainder of the day do not support any severe weather with very
little CAPE and shear. The overcast skies look to continue through
the night hours as well. Daytime highs look to range between the
upper 70s and the upper 80s followed by overnight lows in the middle
50s to middle 60s.
On Wednesday, forecast models show the CWA`s upper air flow turning
west-southwesterly in the morning as an upper air ridge builds in
the central CONUS throughout the day due to the OK/TX upper air
high. A shortwave disturbance is seen passing over the CWA during
the evening hours. At the surface, there looks to some chances for
showers and thunderstorms during the day. CAPE values look to be a
bit better than those on Tuesday around 1000 J/kg in the afternoon
and evening in spots though 0-6m shear values still appear to be low
around 10-20 kts. As mentioned in the previous discussion: cloud
cover through might hinder even these prospective convective
parameters, so this will be monitored going forward in case the
trend starts favoring severe weather. Wednesday`s daytime highs
expect to be in the lower to middle 80 with overnight lows in the
middle 50s to middle 60s.
For Thursday, the west-southwesterly flow looks to continue over the
CWA being underneath ridge throughout the day with shortwave
disturbances traveling through during the evening. A closed upper
air low over CA begins to open up into a trough during the day and
progress eastward with another low well north of it moving over
southern BC. At the surface, there looks to be a warm front passing
through during the day that will warm temperatures. There looks to
be chances for showers and thunderstorms for areas east of the CO
border with the potential for some possible severe weather though
the specifics still look to be a little uncertain at this time.
Forecast model soundings continue to show some possible up to SBCAPE
of 2000 J/kg with 0-6 km shear values around 30 kts. Daytime highs
for Thursday look to be in the lower to upper 90s followed by
overnight lows in the upper 50s to lower 70s.
.LONG TERM...(Friday through Tuesday)
Issued at 207 PM MDT Tue Jun 21 2022
A brief break from the heat expected over the weekend as strong cold
front remains on track to sweep across the region Friday night and
early Saturday morning with strong overall model consensus on this
pattern change. Net result will be temperatures nearly 20 degrees
cooler on Saturday, with even cooler conditions on Sunday.
Temperatures will gradually climb back into the 90s by the middle of
next week.
While confidence is high in frontal passage and resulting impact on
temperatures, precipitation chances remain unclear. With strong
forcing along front, Friday night would seem to be the best chance
for organized precipitation but have a lot of concerns about
potential instability/moisture availability ahead of advancing
front, as sfc fields suggest CWA will be behind dryline as front
approaches. While think the calibrated probabilities in the 40-60
percent range are reasonable, have doubts if there will be much
meaningful precipitation during the period. Threat for afternoon and
evening storms will continue through the start of the week as
easterly sfc flow will potentially bring moist return flow to the
area, with overall synoptic pattern being favorable for ascent
due to proximity of entrance region of H3 jet. Scenario and
potential for meaningful precipitation will strongly be tied to
quality of moisture return advecting to the west around sfc high.
If airmass is drier than expected, precipitation coverage and
amounts will diminish quickly.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 459 PM MDT Tue Jun 21 2022
VFR conditions are expected throughout the duration of the period.
A SW to NE oriented band of showers is expected to slowly move
east through the evening. Broken to scattered skies will continue
overnight with light and variable winds. Winds will become SSE and
breezy mid morning Wednesday with gusts up to 25 knots at each
site.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...076
LONG TERM...JRM
AVIATION...Trigg
Area Forecast Discussion
National Weather Service Green Bay WI
918 PM CDT Tue Jun 21 2022
Updated aviation portion for 06Z TAF issuance
.SHORT TERM...Tonight and Wednesday
Issued at 232 PM CDT Tue Jun 21 2022
A cold front was moving through north central and central WI
this afternoon, accompanied by a wind shift to the west.
Temperatures were warming into the lower to middle 90s ahead of
the front, and dew points in the lower to middle 70s were pooling
near the boundary. This was resulting in heat indices in the
middle 90s to lower 100s over the Heat Advisory area. These will
likely go up a couple degrees over the next couple hours. Despite
the arrival of the cold front and MUCAPE of 2500-3500 j/kg, the
combination of capping in the 850-800 mb layer, weak/shallow
convergence, and minimal upper level support was preventing
convective initiation. Our local meso-analysis page showed CINH
decreasing to 25-50 j/kg near the front, so suspect isolated to
scattered thunderstorms will eventually develop in NE/EC WI later
this afternoon, as depicted by the HRRR and RAP. With DCAPE values
of 1100-1400 j/kg and PWATS of 1.5-1.75 inches in place, could
certainly see localized damaging winds and heavy rainfall with the
stronger storms. However, hail would not appear to be as great a
threat, given marginal deep layer shear (20-25 kts) and wet-bulb
zero heights of 12.5-13K feet. The convection is expected to push
out over Lake Michigan by around 02z/Wed.
Cooler and much less humid weather will move into the area
overnight and into Wednesday, along with moderate west to
northwest winds. Lows tonight should be in the upper 50s to middle
60s. Highs on Wednesday should reach the 70s to lower 80s.
.LONG TERM...Wednesday Night Through Tuesday
Issued at 232 PM CDT Tue Jun 21 2022
The main highlights for the extended period will be the above
normal temperatures from the end of the work week to the early
weekend, along with a couple chances for active weather.
Surface high pressure will start off the extended period
Wednesday night, keeping dry conditions in place across the
region through most of Thursday. Winds will turn to the southwest
over the course of the day Thursday, which will bring back some
very warm temperatures in the middle to upper 80s for the
afternoon highs. Unlike today however, dewpoints will remain in
the 50s, so the overall humidity will be much lower.
As we go from Thursday night to Friday morning, high pressure
will move off to the east allowing a weak shortwave to bring a few
showers to the area. This will mainly impact northwestern and
north- central Wisconsin. Not all the models have this feature at
this time, as a few keep high pressure a little further west,
which would keep most of our neck of the woods dry. The rest of
Friday will also see weak WAA aloft and fairly strong surface
heating. This could allow for a few more chances of precipitation
in the afternoon to evening as some modest instability develops.
Soundings at this time look tall and skinny with minimal shear,
which could support isolated thunder but doesn`t look like the
strongest setup for severe at this time, especially with the
discrepancy on the shortwave still present. Still, kept some
minimal pops in for Friday.
While one eye will be kept on Friday, the other eye will be
watching Saturday, which may be the better day for storm
development. Again we get a strong push of warm air aloft, this
time accompanied with some better PWATs, pushing 2+ inches of
precipitable water across much of the region by the afternoon. As
instability increases during the afternoon, a more definitive cold
front will cross the region as a focal point for any developing
convection. Shear profiles are also a touch more favorable. All
that said, the better parameters will still be to our southwest.
There will also be a big question on how many showers are still in
the region early in the day from anything that happens Friday. So
overall, the best chance for more widespread weather is still
Saturday afternoon, but the overall severe potential remains in
question at this time.
High pressure then moves back in behind the cold front, bringing
in quiet weather for the remainder of the extended.
Temperature wise, a steady increase in temperatures is expected
Thursday and Friday, with highs bordering the 90s. Temperatures
will still be in the high 80s Saturday due to rain potential, but
then make their way back into the 70s at the end of the weekend
into early next week.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 918 PM CDT Tue Jun 21 2022
A cold front drifting through the area early in the TAF period may
lead to an isolated thunderstorm at the ATW/GRB/MTW TAF sites,
while much of the rest of the area will remain dry. Winds will
shift to the west-northwest as the front passes. Some LLWS will
be possible across the central WI TAF sites overnight; otherwise,
good flying conditions expected through the rest of this TAF
issuance.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....Kieckbusch
LONG TERM......Uhlmann
AVIATION.......Cooley
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
1040 PM CDT Tue Jun 21 2022
.SHORT TERM... (Through Late Wednesday Afternoon)
Issued at 234 PM CDT Tue Jun 21 2022
A cold front is moving southeast through Iowa into northern Missouri
this afternoon. The front is expected to progress through eastern
and east central Missouri as well as much of southwest Illinois
tonight and be moving through the eastern Ozarks Wednesday morning.
Nearly all short range guidance shows convection developing on the
front late this afternoon or early this evening over southwest Iowa
and northwest Missouri back into eastern Kansas. This forecast
corresponds well to an area of cumulus that`s developed over Iowa
and northwest Missouri. There doesn`t appear to be much vertical
development at this time due to a strong capping inversion, but it
looks like the cap will be wiped away by an approaching short wave
trough.
The strength and coverage of the convection this evening varies from
model to model, but the consensus forecast is that any storms which
do form this evening will weaken and/or dissipate as they move into
northeast and central Missouri tonight with the cold front. This
scenario is borne out in every piece of deterministic guidance, the
CAMs, and the HREF. In fact, 4hr max updraft strength drops off so
sharply during the late evening/overnight that I`m questioning
whether we`ll see any thunderstorms in our forecast area at all. In
the favor of storms, there should still be plenty of instability
with 1000-1500 J/Kg of MUCAPE ahead of the front according to the
GFS. The RAP shows similar values, if not a bit higher, so will
keep low chance to slight chance for showers and storms in the
forecast, but most evidence points to a mostly dry FROPA. With the
front sagging south on Wednesday, forcing for additional storms will
linger over the eastern Ozarks Wednesday afternoon, but most of the
forecast area should be dry, and somewhat cooler than today.
Carney
.LONG TERM... (Wednesday Night through Next Tuesday)
Issued at 234 PM CDT Tue Jun 21 2022
Any potential for precip should be out of the area by 00Z Thursday,
with the front well south into the Lower Mississippi Valley.
Somewhat a cooler and noticeably drier airmass will filter into the
Mid Mississippi Valley overnight Wednesday night into Thursday, with
surface dew points dipping into the low and mid 60s and highs likely
topping out in the mid 80s to around 90. The respite from heat and
humidity looks brief, as the upper level ridge maintains its grip on
the center of the U.S. at least through Saturday. A vigorous short
wave moves across the northwestern U.S. along the Canada border
Friday, and into the northern Plains Saturday, forcing low level
cyclogenesis as it translates east. This will bring low level
southerly flow back to the Mid Mississippi Valley for Friday and
Saturday ahead of the short wave. Deterministic guidance shows
highs rising back into the low to mid 90s on Friday, and the mid and
upper 90s on Saturday. This looks reasonable as the models show the
thermal ridge at 850mb building smack over Missouri and southwest
Illinois, with temperatures around 22C on Friday and 24-26C on
Saturday. GEFS and NAEFS show 90-97th climatological percentile on
850mb temps on Friday and 97-99th percentile on Saturday. While
ECENS is similar on Friday, it`s warmer on Saturday, approaching
climatological max Saturday afternoon. I therefore still feel pretty
confident in forecasting near-record high temperatures on Saturday
while we`re in the teeth of the thermal ridge.
The short wave moves across the Upper Midwest into the Great Lakes
by Sunday afternoon. Its attendant surface cold front should move
through the Mid Mississippi Valley Saturday night into early Sunday
morning. While the GFS does kick out some precip, the ECMWF shows
very little. The timing of the FROPA is certainly not favorable for
widespread, surface-based convection, so my confidence in getting
much rain with this front is fairly low. However, the upper level
pattern shifts with the short wave trough amplifying over the
eastern 1/3 of the CONUS and the ridge retreating back over the
Rocky Mountains. This puts the Mississippi Valley into northwest
flow and a large cool/dry surface high builds across the Midwest and
Ohio Valley. 850mb temperatures in the ensembles drop to near the
10th climatological percentile 12-14C by Monday, and stay in the 14-
16C range for Tuesday. NBM temperatures for Sunday through next
Tuesday continue to be the warmest, or nearly the warmest of the
guidance suite; however WPC cluster analysis shows a monopole signal
in EOF1 associated with the trough, indicating some variance in
amplitude. This lends more uncertainty to the temperature forecast
out that far, so will stick with the NBM for now.
Carney
&&
.AVIATION... (For the 06z TAFs through 06z Wednesday Night)
Issued at 1031 PM CDT Tue Jun 21 2022
Showers and thunderstorms have formed along the cold front
stretched across western Missouri into central Illinois. Showers
and thunderstorms will continue along the front as it drops
southeast through the region, though coverage is expected to
diminish as it does. MVFR flight conditions are expected briefly
if a shower or thunderstorm moves across the terminal space. This
is most likely to occur at KUIN during the first hours of the TAF
period. Confidence is significantly lower that showers and
thunderstorms will impact the mid-Missouri and St. Louis metro
terminals. VFR flight conditions will prevail in the wake of the
front and associated precipitation. Winds will shift from
southwesterly to the northwest as the front moves through the
region.
MRM
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 77 92 71 91 / 10 30 5 0
Quincy 71 87 66 87 / 30 10 0 5
Columbia 72 89 68 88 / 30 30 5 5
Jefferson City 73 90 68 89 / 20 30 5 5
Salem 74 94 68 90 / 5 30 0 0
Farmington 72 92 66 89 / 5 30 5 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Paducah KY
625 PM CDT Tue Jun 21 2022
.UPDATE...
Issued at 621 PM CDT Tue Jun 21 2022
Updated aviation discussion for 00z TAFs.
&&
.SHORT TERM...(Tonight through Thursday night)
Issued at 300 PM CDT Tue Jun 21 2022
The main concerns in the short term portion of the forecast will
be return of triple digit heat index values and the potential of
isolated to scattered thunderstorms Wednesday afternoon. The
latest RAP analysis shows a 595 dm ridge centered over the Mid-
South. Temperatures have responded accordingly, with values in the
middle to upper 90s at most locations. Dew point values have also
crept back into the lower to middle 60s. Tonight will be warm
with clear skies as we remain under the influence of surface high
pressure over the southeast CONUS. Low temperatures will generally
fall into the lower 70s.
On Wednesday, a weak surface boundary will begin to move from NW
to SE across the forecast area. Dew points will pool ahead of this
boundary, increasing into the lower 70s Wednesday afternoon. It
will be another very hot day, with high temperatures again in the
middle to upper 90s. This will result in widespread heat index
values of 100 to 105 degrees during the heat of the day. Since 105
is the threshold for a Heat Advisory, decided to issue a Special
Weather Statement highlighting the heat risk and let the midnight
shift decide on the need for a formal heat headline. Isolated to
scattered thunderstorm development is expected (PoPs of 15-30%)
from late morning through the afternoon ahead of the cold front.
The environment will be typical for summertime pulse convection in
our region, with plentiful instability (MLCAPE values around 2000
J/kg) but very little shear. Forecast model soundings show quite
a bit of mid- level dry air, so the potential for a few severe-
level downbursts is there in the afternoon. SPC has a marginal
risk for the northeast part of the forecast area, and that looks
OK for now.
Behind the frontal passage on Thursday, (slightly) cooler and less
humidity conditions will arrive on the heels of a northerly wind
shift. High temperatures will range from the upper 80s to lower
90s. Dew point temperatures will be firmly in the comfortable
range, in the upper 50s to lower 60s.
.LONG TERM...(Friday through Tuesday)
Issued at 300 PM CDT Tue Jun 21 2022
Mid level heights are forecast by the medium range models to begin
rising again by the beginning of the extended forecast period. A
minor disturbance might generate a bit of measurable rainfall north
of I-64 Sat morning, but otherwise, the main story will be the heat
on that day as a ridge aloft strengthens ahead of a northern stream
mid level shortwave. The NBM temps provided by Forecast Builder
appeared to be somewhere near the 50 percentile, and this signal has
been around for a while, so it seemed reasonably reliable. Surface
dewpoints in the 50s Fri are forecast to rise into the 60s by Sat,
but no more, due to lack of robust moist return flow. Upper 90s
temps are forecast Sat afternoon, with 100 possible in a few spots.
Heat indices of mid/upper 90s are expected in the eastern half of
the PAH forecast area, with 100+ expected in the western half. In
fact, the westernmost parts of southeastern MO may reach 105+. This
will be followed by tepid lows Sat night in the middle 70s.
The models appeared to be in reasonable agreement depicting a
vigorous mid level shortwave, moving rapidly eastward near the
U.S./Canadian border during the weekend. This will be the impetus
for a surface cold front sweeping through our region on Sun. This
feature will be rather moisture-starved with deeper moisture to our
south and east, so QPF will be also limited for us. Isolated to
scattered showers/tstms will probably pop up mainly during the
daylight hours. At this time, wind shear appeared limited in the
models, in addition to lapse rates. All pcpn should be out of
eastern parts of the region by the wee hours of Sun night.
The new airmass will provide northerly to northeasterly winds and a
moderation of temps. Starting Sun night, lows will be back in the
60s across the region, with highs in the 80s.
&&
.AVIATION...
Issued at 621 PM CDT Tue Jun 21 2022
Clear skies and calm winds expected tonight. Winds switch around
to northwesterly 5-10 kts tomorrow behind a cold frontal passage
early. There likely will be some isolated to scattered showers
and storms around after 18z tomorrow, but confidence is low in any
one terminal being impacted at this time. Brief vsby reductions
and gusty winds would be possible with the heavier activity.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...SP
SHORT TERM...DWS
LONG TERM...DB
AVIATION...SP
Area Forecast Discussion
National Weather Service Blacksburg VA
913 PM EDT Tue Jun 21 2022
.SYNOPSIS...
High pressure increases from the west through tonight. Meanwhile
a frontal system will slide southward toward the mid-Atlantic
Wednesday, passing through by later Thursday. Ahead of the front
expect increasing heat and humidity and a chance for showers
and thunderstorms as the front crosses the Mid Atlantic region
on Wednesday night and Thursday. High pressure and a lower
probability of showers and thunderstorms are expected for Friday
and Saturday.
&&
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
As of 913 PM EDT Tuesday...
Made some minor adjustments to temperatures and dew points
for tonight. Modified weather and pops a little for Wednesday
during late afternoon. More changes to forecast after 00z models
come in.
Previous discussion:
As of 635 PM EDT Tuesday...
Dry tonight, then chance of showers and storms late Wednesday.
Made some minor adjustments in temperatures for this evening
into tonight utilizing the latest surface obs, their trends and
blended in the NBM. Low temperatures overnight will range from
the mid 50s in the mountains to the lower 60s in the piedmont.
The upper low/trough off the Northeast coast starting to head
west toward the mid-Atlantic coast by Wednesday afternoon.
A disturbance rides atop the ridge from the Great Lakes region into
the Appalachians Wednesday afternoon into Wednesday night. HiRes
Models like NAMnest and HRRR show convection dropping south
across the region after 20z. SPC highlighted the potential for
strong to severe storms with the marginal risk in Day 2
Convective Outlook. Healthy MLCAPEs with weak shear expected
with the thunderstorms. The main threats would be winds and
hail with the stronger updrafts.
High confidence in Near Term Forecast.
Previous discussion:
As of 115 PM EDT Tuesday...
Going drier through most of the period with increasing heat...
Despite the heat increasing due to the upper ridge over the
lower MS Valley into the southern Appalachians, the surface flow
has been more out of the north and as such, dewpoints have been
held in check.
Area should remain dry through most of Wednesday, with upper
low/trough off the northeast coast starting to head west toward
the mid-Atlantic coast by Wednesday afternoon. Some model
differences in potential disturbance riding atop the ridge from
the Great Lakes into the central Appalachians Wed afternoon,
with most showing main lift and forcing east/northeast over the
mid-Atlantic/Delmarva area. Will allow for low chance pops to
reach the I-64 corridor Wed afternoon, with maybe an isolated
storm as far south as the U.S. 460 corridor.
Will see if any convective blowoff occurs if more organized
activity develops upstream. For now will lean toward previous
and MAV with mid 90s east, to mid 80s/near 90 west of the Blue
Ridge.
Forecast confidence is high for all elements through midday
Wednesday then shift to average for temps/sky/pops Wed
afternoon.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
As of 230 PM EDT Tuesday...
Showers and storms through Thursday, quiet Friday...
A trough through the Great Lakes and eastern Canada will drop a
frontal boundary to the south. This front crosses our area late
Wednesday, and begins to stall as it becomes distanced from the
forcing of the trough. While the front lingers near the Carolinas
through Thursday, it will serve as an initiator of storms Wednesday
night through Thursday afternoon. By late Thursday, a closed upper
low off the Mid-Atlantic coast will pick up the boundary and become
part of the northern stream, thus pulling the stalled front out of
the area by Thursday night. With a large broad ridge centered over
the southern plains and no dynamics in play near our CWA, Friday
will be a return to quiet, summery conditions.
Daily highs will be in the 80s and 90s throughout this forecast
period, but an influx of moisture will raise dewpoints 5-10 degrees
from where they started earlier this week. So despite being a few
degrees cooler on Thursday and Friday than it will have been
Wednesday, the increased humidity will make it feel just as hot, if
not a bit warmer.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 230 PM EDT Tuesday...
Hot and humid before a front brings showers early next week...
Saturday will also see our area underneath a surface high, but given
the increased moisture and temperatures, we maintain slight chance
to chance PoPs for diurnal storms Saturday afternoon and evening.
That high will be pushed out of the area beginning Sunday as an
upper trough barrels across the northern plains and enters the Great
Lakes region by Monday. A front will come along with it, dangling to
the south and crossing our area early next week on Monday or
Tuesday, timing is not quite settled yet with this system. The
trough is well agreed upon by most guidance, so confidence in an
early week system bringing showers and storms is high. The weekend
will be summery with temperatures above normal, and then a little
cooling behind the early week system.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
As of 635 PM EDT Tuesday...
VFR conditions will prevail tonight through Wednesday morning. A few
mid/high clouds with winds staying mainly west-northwest and under
10kts. An disturbance will ride atop the ridge from the Great Lakes
into the central Appalachians Wednesday afternoon. The best lift and
forcing remains east and northeast over the mid-Atlantic/Delmarva
area. Isolated to scattered MVFR showers and thunderstorms look to
move in from the north later Wednesday afternoon, with best chance
not til after 00z.
Above average confidence for ceiling, visibility and wind.
Extended Aviation Discussion...
A cold front crosses the region Thursday, so despite the storms most
areas should stay VFR, with sub-VFR in any tstms.
Mainly VFR conditions through Saturday, with isolated storms
possible Saturday. Could also have late night fog brought on by rain
and increased RH. Sunday looks unsettled with scattered MVFR showers
and thunderstorms, mainly during the afternoon and evening
hours.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...WP
NEAR TERM...KK/WP
SHORT TERM...VFJ
LONG TERM...VFJ
AVIATION...KK/WP
Area Forecast Discussion
National Weather Service San Diego CA
225 PM PDT Tue Jun 21 2022
.SYNOPSIS...
An upper low off Point Conception will draw monsoonal moisture
northward into southern California tonight through Wednesday,
leading to the development of scattered showers and isolated
thunderstorms which will be most prevalent over the mountains and
deserts on Wednesday. Thunderstorms could produce strong gusty
winds and brief heavy rainfall. Drier southwest flow aloft will
develop on Thursday with a slight chance of thunderstorms in the
afternoon, mainly over the mountains. Then drier with warming
conditions Friday through Saturday. Monsoonal moisture could move
back in early next week.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
-Forecast Highlights-
* First monsoonal moisture surge of the season is here
* Result will be scattered showers and isolated thunderstorms
* Low risk of flash flooding mountains and deserts on Wednesday
The first monsoonal moisture surge of the season has arrived!
Looking out the window we are seeing beautiful altocumulus clouds
increasing from the south. This could lead to an amazing sunset
this evening. These clouds are indicative of mid level moisture
moving northward from Mexico on south-southeasterly mid level
steering winds. SPC mesoanalysis shows Precipitable Water (PW) at
less than 0.50 inches over Orange County with 0.80 inches near the
international border. PW near 1.5 inches resides over the
northern Gulf of California. A southeast moisture surge will send
higher PW of 1.0-1.4" into SoCal (highest near the border) with
surface dewpoints even soaring into the lower-mid 60s into at
least southern parts of the Coachella Valley by Wednesday morning.
It will be a bit more humid elsewhere as well associated with
this monsoonal push.
The moisture advection is taking place to the east of an upper
low off Point Conception. HRRR shows scattered showers developing
reaching into Southern San Diego County after midnight with
movement from south to north across the region through Wednesday
morning. Point forecast soundings show little instability with
CAPE off global and hi-res models less than 100 J/KG, but often
elevated convection can be underestimated, so we have kept a
slight chance of thunderstorms in the forecast after midnight
through Wednesday morning. There is a stronger signal for elevated
tstorms to the north of our service area late tonight- Wednesday
morning.
Rainfall amounts overnight-Wednesday morning will mostly be
trace-0.10 inches in the shower activity, perhaps up to 0.25
inches at higher elevations (less evaporation - closer to the
moisture).
By Wednesday afternoon, monsoonal moisture will be fully in place
and with surface mass convergence expected to occur over the
mountains, this looks to provide the best opportunity of
thunderstorms to develop with southwest steering flow oriented
towards the deserts. The highest thunderstorms chances will be
from the San Diego County mountains extending north to the Santa
Rosas where localized amounts of 0.50-1.00 inches will be
possible. Most cells will produce 0.25-0.50 inches. Overall lesser
rainfall amounts will impact the San Bernardino County mountains.
There is a low risk of flash flooding over the mountains and
deserts Wednesday afternoon into early evening.
Strong downburst winds are a possibility in the thunderstorms as
well. This risk is highest with any thunderstorms that move out
over the deserts in an environment favorable for microbursts
(inverted V sounding/very dry air sub-cloud level).
The aforementioned low near Point Conception will move east across
central California on Thursday with westerly steering winds
sending the monsoonal moisture off to the east. There may be just
enough moisture remaining Thursday afternoon to allow for isolated
showers or thunderstorms to develop over the mountains on Thursday
before dry weather returns Friday and into the upcoming weekend
while temperatures warm by a few degrees.
Another slight increase in monsoonal moisture may enter the
picture again early next week to allow for a returning risk of
showers/tstorms for the mountains and deserts.
Temperatures overall will run above average through the period
with the hottest conditions expected this upcoming weekend.
&&
.AVIATION...
212100Z....Mostly clear skies with unrestricted vis expected
through early this evening. Increasing mid-level clouds will occur
with bases AOA 10,000 FT MSL. Low to moderate chance of low
clouds 800-1000 ft MSL impacting coastal areas after 07Z tonight.
This would be accompanied by vis restrictions 1-3SM if these
clouds do impact the coast.
&&
.MARINE...
No hazardous marine weather is expected today. There is a slight
chance of showers and thunderstorms across the coastal waters late
tonight into Wednesday, with isolated cloud-to-water lightning being
the primary concern. Breezy northwest winds will occur each
afternoon and evening late this week into this weekend.
&&
.FIRE WEATHER...
An upper low off of Point Conception will draw monsoonal moisture
northward into southern California tonight through Wednesday, leading
to the development of scattered showers and isolated
thunderstorms which will be most prevalent over the mountains and
deserts on Wednesday. Thunderstorms could produce strong gusty
winds and brief heavy rainfall. Scattered showers are forecast to
spread northwestward across the area late tonight into Wednesday
morning. A thunderstorm cannot be ruled out. The threat of dry
lighting is low. Thunderstorms are most likely to occur over the
mountains Wednesday afternoon but they are expected to contain
wetting rainfall. In fact, a few heavy cells are possible.
Drying is expected to begin on Thursday, but there could still be
enough residual moisture for isolated thunderstorms near the
mountains Thursday afternoon.
&&
.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...Gregoria
AVIATION/MARINE...APR