Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/20/23
Area Forecast Discussion
National Weather Service La Crosse WI
1052 PM CDT Tue Sep 19 2023
.DISCUSSION...(This evening through Tuesday)
Issued at 210 PM CDT Tue Sep 19 2023
Key Messages:
- Rain chances through Wednesday (Spotty-10-30% due to low confidence
in location/coverage)
- Still some uncertainties in how the upper level pattern will
evolve for the weekend. Even so, there is continued signal for
increasing shower and storm chances.
*Overview:
By mid-morning, the shortwave trough was pushing across southern
Wisconsin with the general rain area south of the forecast area.
Rainfall amounts from the evening and overnight rains were generally
from 0.20" to 1.00" and covered parts of southeast MN, northeast IA,
and southwest WI. The Rochester airport reported thunder but no
rain, KLSE had 0.19", however Onalaska only had 0.01" and at the NWS
La Crosse, we measured 0.13". Lancaster WI had 0.72"
and the Platteville, WI area reported .5 to 1".
GOES water vapor satellite imagery, heights and lightning showed
several embedded shortwave troughs over parts of WI/IA/ern Neb. with
additional trough energy over CO/KS/OK in the zonal flow. Additional
longwave troughing was noted over western Canada/Pacific Northwest
and a closed low off the California Coast. The latest surface map
has surface high pressure over Michigan with an elongated area of
low pressure from Manitoba southward through the Plains States. A
warm front stretched from southwest Iowa into northern Missouri.
There is the hint in the surface pressure of a front from southeast
MN into central WI in the area of the 850mb front.
Storms were re-developing with the shortwave trough over parts of
western and central Iowa by late morning.
*Through Wednesday- Showers and storms still spotty, but will try
to increase Wednesday for some:
As the weak 500mb shortwave drifts east and we maintain deep low
level moisture and some mid-level moisture, we will continue to see
some shower and storm activity. The CAMs/HREF have a spattering of
precipitation along the southern fringes of the forecast area with
an increase after 08z and some northward lifting across parts of the
forecast area. The HiRes-ARW is more west, while the HRRR is more
east, while the RAP is west to east Wednesday. The storms over Iowa
have not been moving much off the outflow boundary. Recent radar
shows a southward push off the eastern portion of the line and more
of an eastward drift and weakening of the western part of the line.
Additional development may have trouble developing farther north.
Due to lower than usual confidence, will include small pops to
account for the uncertainty and location of showers storms with the
shortwave, continued theta-e advection, moisture transport and some
increase in instability (MLCAPE 200-1200 J/kg) overnight to 1000-
2500J/kg Wednesday.
*Wednesday night through early next week- Increasing weekend
shower and storm chances:
Lower confidence shower and storm chances continue to spot the
forecast as guidance shows multiple impulses move across the
region. As the shortwave continues to lift north/northeast across
the forecast area late Wednesday through Thursday, there remains
some variability in guidance on the continued development and
progression of showers. As mentioned earlier, will maintain small
precipitation chances to account for this uncertainty. Through
this time, a deep closed upper level low is still forecast to drop
down through the northwestern U.S., eventually progressing
eastward and slowing down towards the north- central states. Low
shower and storm chances /15-35%/ continue heading into the
overnight Thursday and through Friday as impulses eject out ahead
of the incoming trough. From there uncertainty still remains in
the evolution and progression of this upper level pattern through
the weekend, though, as the upper level low moves eastward
ensemble guidance suggests increasing shower and thunderstorm
chances should expand into the region. The main question just
becomes how much. There looks to be plenty of moisture as NAEFS
and ECMWF both show PWATs in the 90th percentile of climatology,
so heavier rainfall potential will be something to monitor. Though
hard to pinpoint exact details now, will also be worth watching
the risk of severe weather as SPC has highlighted a small portion
of northeastern IA and southeastern MN in the Saturday outlook.
As expected with the uncertainties in the pattern, there is lower
confidence in how long shower and storm chances will linger.
Otherwise, a general decreasing trend in high temperatures looks to
end the weekend and start the new week (upper 60s to low 70s).
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1051 PM CDT Tue Sep 19 2023
VFR conditions are expected through the TAF period. The biggest
forecast concern remains the possibility of showers and storms (20-
30% chance) across parts of southeast Minnesota, northeast Iowa, and
western Wisconsin Wednesday afternoon and evening. Confidence is too
low to add impacts to the TAFs at this time, but visibility
restrictions are possible if showers/storms develop.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
DISCUSSION...EMS/Zapotocny
AVIATION...KAA
Area Forecast Discussion
National Weather Service Des Moines IA
641 PM CDT Tue Sep 19 2023
...Updated for the 00z Aviation Discussion...
.DISCUSSION.../Tonight through Tuesday/
Issued at 253 PM CDT Tue Sep 19 2023
Key Messages:
-Showers and sub-severe thunderstorms continue to fester through
the afternoon and evening; heavy rain, small hail, and gusty
winds possible
-Sporadic showers and thunderstorm chances through the rest of the
week
-More robust system moving in this weekend
As was somewhat alluded to by short-range guidance yesterday,
scattered showers and thunderstorms have festered through the
morning hours and into the early afternoon, although storms have
been further north and far more robust than was anticipated
yesterday. This convection has been anchored to a region of warm air
advection aloft and embedded within a region of marginal
instability. Most-Unable CAPE values as analyzed by the SPC meso-
analysis page are only ~1000 J/kg aloft and wind profiles have
diminished through the morning, leading to sub-severe shear values
and pulse thunderstorms that are producing primarily dime to nickel
sized hail. Rainfall with these storms today have also been more
efficient than previously anticipated, primarily due to slow moving
storms training over the same areas. Those that have been under the
precipitation today have seen anywhere from 1 to 3 inches of
rainfall. Fortunately, dry conditions have allowed for this to be
mostly absorbed by the dry soils. Despite CAMs such as the HRRR
trying to dissipate the storms today, they don`t actually show any
signs of stopping, so anticipating that these will fester along
the Hwy 30 corridor and south through the rest of the afternoon.
Heavy rain, small hail and gusty winds will all remain possible.
Flash flooding likely wont be a concern in most places, but urban
areas could see some ponding if this line stalls out over top of
them.
This pattern of poorly resolved, scattered showers and thunderstorms
continues through much of the week, as we reside in a weakly forced
but highly perturbed upper level pattern. This is resulting in a
large amount of variation between CAMs and global models alike,
which has translated to a smattering of precipitation chances in the
forecast. As was mentioned in previous discussions, rain likely wont
fall for all those who have rain in their forecast, nor will it fall
for the entire period chances are present, but with the sporadic
nature of storms there will be a chance of rain/storms in these
areas through much of the week. Fortunately, the severe chances with
any precipitation looks minimal. There will be periods of relatively
higher instability (1000 to 2000 J/kg), but due to the weak flow
aloft it will be difficult for much of anything to organize. That
being said, pulsey pop up storms would still be capable of producing
small hail and gusty winds, much like we`ve seen today.
Looking later into the week and towards the weekend, we`ll see an
intensifying trough develop over the western CONUS which will bring
us a couple different rain and thunderstorm chances starting late
Thursday and lasting periodically through the weekend. Global models
are indicating at multiple lobes of energy rotating around the
digging trough through the weekend, with the first coming Thursday
night into Friday morning, the second being Friday night into
Saturday morning, then the third being Saturday into Sunday. The low
then stalls out overhead into early next week, bringing even more
precipitation chances as it slowly departs through the area Monday
into Tuesday. Needless to say, this would result in quite a wet
weekend with storm chances possible on multiple days. Severe weather
will also be possible, especially Friday night and Saturday night
when instability is highest and wind fields are most prominent
around the low, supporting more deep layer shear. This is echoed in
both the SPC Day 5 outlook (15% chance of severe weather over our
area) as well as the CSU machine learning algorithm`s day 4 and 5
severe weather outlook. This is still multiple days out there, so
its too early to get too locked into the details, as things will
likely still change. However, models are coming into decent
agreement and the trend has been fairly consistent for at least a
rainy weekend, so this is definitely a system to keep on your radar
if you have any weekend plans!
&&
.AVIATION.../For the 00Z TAFS through 00Z Wednesday evening/
Issued at 641 PM CDT Tue Sep 19 2023
Thunderstorms will continue to impacts sites KDSM/KOTM this
evening, expected to taper off towards 06z. VFR overcast skies
persist through much of the remaining TAF period across most
sites, beginning to diminish north at KFOD/KMCW towards the end
of the TAF period.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...Dodson
AVIATION...Hagenhoff
AREA FORECAST DISCUSSION
National Weather Service Hastings NE
636 PM CDT Tue Sep 19 2023
...Aviation Update...
.DISCUSSION...(This evening through Tuesday)
Issued at 457 PM CDT Tue Sep 19 2023
-- KEY MESSAGES FOR THE ENTIRE 7-DAY FORECAST:
(generally chronological order)
* MOST areas dry/storm-free through Wed night:
Although there could be some very isolated/spotty (and likely non-
severe) thunderstorm activity late this afternoon-evening and
again Wed afternoon-evening, the vast majority of our coverage
area (CWA) will likely remain dry through at least sunrise Thurs.
* Various rounds of showers/storms (some likely severe) between
Thursday-Saturday:
Although still plenty of "finer details" to work out (especially
given a somewhat complex upper air pattern with various lower-
amplitude waves preceding the eventual primary upper low), at
least a few rounds of showers/storms are still looking likely
between Thurs daytime and Saturday. Most of the CWA is already
under an SPC Marginal Risk (level 1 of 5) for severe storms mainly
for late Thurs afternoon-evening and most of the CWA is also
already highlighted in a Day 4 Slight Risk (equivalent) for
Friday, and if the latest ECMWF is onto anything then especially
eastern zones could be under the gun for Saturday afternoon
before the main upper system/surface front sweep away appreciable
instability. Main threats would be the usual large hail/damaging
winds, but early glances at a decent combo of instability/shear
would also suggest a non-zero tornado threat in that Fri-Sat time
frame, so this bears watching.
* Temperature overview: A modest cool-down beyond today (and
especially beyond tomorrow):
Following a couple of days that got legitimately hot by mid-late
September standards (yesterday and today), we have one more day of
solidly above-normal warmth on Wednesday (highs mainly mid-upper
80s) before a more noticeable downward trend with highs mainly in
the mid 70s-low 80s range commences Thursday onward. Despite this
cool-down, there are currently no appreciable signs of any kind of
"truly chilly" fall air anytime soon, with both the latest ECMWF
ensemble data and official CPC Day 8-14 outlook (valid Sep.
27-Oct. 3) leaning pretty solidly toward above-normal highs into
the mid-70s to low 80s range.
* Some uncertainty regarding how dry it will be Sun-Tues:
Looking toward the very end of the 7-day, there are probably more
questions (compared to 24 hours ago) regarding how quickly (or
slowly) any "wrap-around" rain shower potential departs behind
this weekend`s system. Per the typically faster/more progressive
GFS, all three of these days could be dry CWA-wide. However, the
ECMWF (and particularly this latest run) has thrown a wrinkle by
greatly slowing the departure of the main low this weekend, and
keeping at least light/spotty rain potential going (especially in
northern/eastern zones) right on through Tuesday. Obviously plenty
of uncertainty this far out, but our latest forecast maintains
some low rain chances/PoPs for this time frame mainly north/east
to account for the ECMWF scenario.
-- MORE DETAILS/INFO BUILDING UPON KEY MESSAGES ABOVE (including
all further discussion of Days 2-7 Thurs-Tues):
- Biggest changes (if any) versus previous (overnight) forecast
package:
Honestly, no major changes to speak of, as the general theme of
Thurs-Sat being by far the most active portion of the 7-day
forecast remain firmly intact. The main changes involved minor
temperature nudges, mainly a very slight downward nudge for
Thursday (due to expectation of quite a few clouds/some precip
around), and slight upward nudges mainly for Saturday (likely
trending toward a slightly-slower cold front arrival).
- General overview of the large-scale upper air/surface weather
pattern (chronological):
1) Tonight-Wed night:
The vast majority of our CWA likely remains dry as our flow aloft
gradually transitions from its current west-northwesterly to more
southwesterly as a large-scale trough/closed low eventually takes
form over the northwestern CONUS.
2) Thurs-Sat night:
As mentioned, we still have some work to do on the "finer details"
of rain/thunderstorm/severe storm chances during this time, as the
"exact" timing of various low-amplitude waves will be key, along
with of course exactly how/when the MAIN upper low kicks out
across the Plains. As it currently stands per latest ECMWF/GFS, we
get one weak upper wave passing through Thurs afternoon-evening,
another lead-wave centered on Fri afternoon-evening, and then
finally the main/parent upper low slow enters/drifts across mainly
parts of SD/NE Sat-Sat night, while also driving through a
dryline/cold front in the process (which could be a severe weather
maker as it does so).
3) Sun-Tues:
As also hit on above, probably one of the bigger changes in the
model world (versus 24 hours ago) is that both the ECMWF/GFS (but
especially ECMWF) have trended slower with the departure of the
gradually-weakening main upper low (and subsequent building-in of
riding from the west). Taking the latest deterministic ECMWF at
face-value (of course its far too early to do this), PoPs for
"wrap around" rain showers may need increased during this time,
and our going temp forecast could actually be a bit too warm.
-- SHORTER TERM DETAILS FOCUSED SOLELY ON THE NEXT 36 HOURS
(through late Wed night/early Thurs AM):
- CURRENT/RECENT WEATHER SCENE AS OF 415 PM:
Most notably, for the second-straight day, temperatures have
exceeded forecast expectations by at least a few degrees most
areas, with most of the CWA on track to top out in the 90-94 range
(Grand Island actually got within 4 degrees of its Sep. 19 record
of 98 that was just set last year). Turning to the mid-upper
levels, water vapor satellite and short term model data confirm
broad west-northwest flow over the Central Plains, with a low
amplitude disturbance centered just to our east (generally over
the NE/IA) border helping to drive more widespread/persistent-
than-expected thunderstorm activity over parts of IA today. With
our CWA just behind this wave, it`s been a dry day for at least ht
vast majority of the CWA, under a mix of sun and high clouds.
Wind-wise, as expected they have been lighter than yesterday, with
speeds in most areas this afternoon no more than 5-10 MPH and
generally from a southerly/easterly direction owing to a very weak
pressure gradient (except for some higher gusts 0f 15+ MPH in
mainly far southeast zones (around Hebron/Beloit).
- LATE THIS AFTERNOON-TONIGHT:
Odds strongly favor the vast majority of the CWA remaining dry, as
we remain "in between" subtle disturbances aloft, and largely
absent of any lower-level jet convergence. That being said, opted
to go with a basic "slight chance" (20 percent) of
showers/thunderstorms for mainly parts of our KS and far western
Neb CWA through 11 PM or so, just in case some fairly weak/high-
based activity is able to "pop" during and slightly after peak
heating. A few models (including latest NAMNest) suggest that
evening shift will also have to keep an eye on our far northeast
CWA (mainly Polk/York area) to make sure something isolated also
doesn`t flare up there before nightfall, but at least for now kept
a dry forecast going in that area as the last several HRRR runs
keep that area at least weakly-capped. In other departments, while
the night will start out no worse than partly cloudy most areas,
various models (especially NAM) suggest that much of especially
the southeast half of the CWA could see a "slug" of low clouds
advect in from the south-southeast between midnight-sunrise.
Should this occur, suppose a ribbon of at least light fog could
develop along the west-northwest edge of these clouds, but kept
any official fog mention out of the forecast for now given low
confidence. Breezes overnight will be light and mainly southerly
(especially east), which will result in a moisture/dewpoint
boundary of sorts. This moisture discontinuity, along with
invading lower clouds southeast, will likely promote at least a
10-degree gradient in low temps tonight, and have them aimed form
low 50s far north and west-central, to low 60s southeast.
- WEDNESDAY DAYTIME-EVENING:
Starting with higher-confidence items, confidence is high that at
least the vast majority of the CWA remains dry through late
afternoon/early evening, as we continue to remain in a zone of
minimal forcing aloft. That being said, a wave approaching from
the west late in the afternoon looks to spark off some
isolated/scattered (and mainly weak) thunderstorm activity MAINLY
just to our west over western NE. However, with higher-res models
suggesting that some of this activity could at least clip of our
far western zones, introduced slight chance of storms to areas
mainly west of an Elm Creek-Alma line 4 PM-Midnight. In lower-
confidence aspects of the forecast, are questions about how
quickly (or slowly) any low cloud deck present in the morning
clears out. For now, our forecast leans toward a fairly aggressive
clearing (especially for the afternoon), but this is not a sure
thing. Obviously this could easily have at least a 5-degree impact
on high temps, but for now made little change to previous forecast
with most areas aimed into the 83-87 range. Breezes will be a bit
steadier than today (mainly in the afternoon), generally 10-15 MPH
from the south-southeast.
- WEDNESDAY LATER NIGHT:
Although it`s not "guaranteed" dry, opted to follow the lead of
higher res-models and keep the midnight-sunrise time frame void of
mentionable PoPs at this time. That being said, the usually low-
level moisture-aggressive NAM tries to saturate the low-level
enough to generate at least patchy drizzle. Not ready to buy into
this just yet, but something to watch going forward. At the very
least, expect increasing lower cloud as the night wears on, in the
presence of generally 5-10 MPH southeasterly breezes. Low temps
should be a bit more uniform across the CWA than tonight, and have
most areas aimed 58-61. Also like tonight, there is probably a
chance for at least some light fog, but just wasn`t enough of a
solid signal in higher-res models to formally introduce to the
forecast.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Thursday)
Issued at 634 PM CDT Tue Sep 19 2023
VFR conditions persist this evening at both terminals. Expect
light and variable winds at KEAR, with winds out of the south at
KGRI through the evening and overnight hours. A few low clouds are
expected to move into the region overnight, moving out tomorrow
afternoon. Wind remain generally around 5-10kts from the south-
southeast tomorrow.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
DISCUSSION...Pfannkuch
AVIATION...Wekesser
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
749 PM CDT Tue Sep 19 2023
.UPDATE...
Issued at 749 PM CDT Tue Sep 19 2023
The forecast appears to be on track this evening.
A recent hand surface analysis places a surface warm front
stretching from a weak surface low pressure system near Omaha, NE
southeastward to just east of St. Louis, MO. A second, more diffuse,
warm front is draped from near Moline, IA to Rensselaer, IN. A few
showers continue to percolate north of the secondary warm front
across the Chicago metropolitan area, apparently tied to subtle
isentropic ascent atop the frontal boundary being forced by an
intensifying 25-30kt 925-850mb low-level jet. As the low-level jet
continues lifting northeastward, any remaining showers should become
confined to far eastern Wisconsin and Lake Michigan over the next
few hours.
Meanwhile, a somewhat disorganized cluster of showers and
thunderstorms that originally developed earlier this afternoon
continues to fester across central Iowa. Recent radar imagery shows
signs that a broad mesoscale convective vortex is developing,
currently centered just to the east of Des Moines. With about 15-
20kt of westerly steering flow, the developing MCV appears on track
to drift eastward this evening and cross the Mississippi River after
midnight near the intersection of the aforementioned synoptic and
secondary warm fronts. With the increase in mesoscale forcing and
southerly enhancement to the low-level jet ahead of the circulation
atop the broad combined warm frontal zones, a gradual increase in
shower coverage remains on track for our area overnight seemingly
centered near the I-88 and I-80 corridors. Coverage of showers may
continue after sunrise before fading by mid-Wednesday morning as the
low-level jet wanes.
While PWATs are not overly high (00Z DVN/ILX RAOBs sampled around
1"), slow shower motions, MUCAPE between 250-500 J/kg, and augmented
dynamic lift near the center of the MCV may nevertheless promote
surprisingly efficient rain rates especially if convective elements
can develop within an otherwise meagerly unstable regime. If showers
and embedded thunderstorms were to focus along a narrow axis,
isolated rain totals above an inch would certainly be in play
overnight. For what it is worth, the NAM3 seems to provide a
"worst case scenario" with narrow pockets of 2-3" within an
otherwise broad brushed 0.25" or so, which on top of wet soil may
lead to localized ponding in ditches and low-lying areas as well
as rises in creek and river levels. Confidence in where such an
axis of heavier rain may materialize, if at all, is fairly low
(less than 10 percent chance?). At any rate, you can never leave
your guard down when mesoscale circulations ride along frontal
zones.
That is all to say that, again, the forecast appears on track.
Limited updates were made to the gridded forecast database, and
updated products will be sent soon.
Borchardt
&&
.SHORT TERM...
Issued at 300 PM CDT Tue Sep 19 2023
Through Wednesday night...
* Showers decreasing in coverage this afternoon from west to east.
* Additional scattered showers and storms possible late tonight
into early WED AM.
* Warmer on Wednesday with highs in the upper 70s to lower 80s.
High-based showers continue early this afternoon across much of
the area but have decreased in coverage. Small droplet sizes has
aided in fairly decent albeit brief visibility drops to as low as
1-2 miles. These showers will continue to decrease in coverage as
the back edge shifts from west to east. There are a few convective
looking elements that could try to throw out a stray lightning
strike or two, but overall the lightning threat continues to look
low. Areas where rain and overcast skies have persisted for much
of the day have been slow to warm up, with temperatures still in
the upper 60s to lower 60s, generally along and north of I-80.
Locales well south of I-80 toward central Illinois have seen less
cloud cover and reside on the warm side of the warm front, having
warmed into the lower 80s.
Confidence in the precipitation forecast is on the lower side for
late tonight into early Wednesday morning. This will ultimately
be determined by the placement of a narrow 800-700mb moisture
layer coincident with better lapse rates. If this layer can
saturate sufficiently, the steeper mid-level lapse rates would
result in sufficient instability for lightning. Initial thoughts
are that the better potential exists west of the Chicago metro and
then extending into the northern suburbs. Hi-res guidance has not
had the best track record on some of these more subtle warm
advective-type storms of late and continue to bounce around in
location quite a bit from run to run. For now opted to lean on
the 15Z RAP and have 20-30% chances for showers and thunderstorms
generally along and north of I-80 after midnight through daybreak
Wednesday, but in reality it could end up anywhere in the local
area.
Heading into the daytime hours on Wednesday, any lingering
showers and storms should decrease in coverage and/or lift into
Wisconsin during the morning hours with the afternoon expected to
be dry. Temperatures will be notably warmer than seen for much of
the area today with highs in the upper 70s to lower 80s.
Petr
&&
.LONG TERM...
Issued at 315 PM CDT Tue Sep 19 2023
Thursday through Tuesday...
Key Forecast Message:
* Periodic shower and thunderstorm chances through the long term,
with low confidence in the day to day specifics
A rather messy and complex synoptic-scale weather pattern
featuring many moving parts and pieces awaits us in the long term
forecast period, which reduces confidence in the details.
Big picture-wise, an active southern stream jet will remain in place
over the southwestern CONUS and into the southern/central Plains
through Saturday and will be responsible for multiple consecutive
days of convection and potential severe weather across the
central/southern Plains states. Thursday into Friday, a deep
northern stream trough will be carved out over the Intermountain
West and will interact with the active southern stream jet, while
a Rex block sets up over the eastern half of the CONUS, placing
our region under modest ridging. The western trough should then
eject into the northern/central Plains over the weekend, where it
could then potentially meander around for at least a couple of
days as a closed-off upper-level low.
Of initial interest to our area locally will be how tonight`s
central/southern Plains severe weather episode evolves as guidance
has slowly started to show more support for a solution that involves
an MCV coming out of the Plains convection and slowly lifting
northeastward across Missouri on Wednesday before potentially
reaching our area at some point on Thursday. The 12z model
guidance all in all better resolved this feature, with a slower
northward progression roughly along the mid-Mississippi Valley.
This entails a primarily if not completely dry Thursday morning
for the area, with possible exception of the far west/southwest
CWA.
During Thursday afternoon, our PoPs officially creep up to
chance in the southwest third of the CWA and slight chance for the
remainder of our Illinois zones. Note, however, that some of the
12z guidance, the operational ECMWF in particular, slowed the
progression of the MCV enough to keep the afternoon mainly dry as
well. It appears there will be enough cloud cover, especially with
westward extent, to keep high temps a bit cooler than had been
expected, though away from the lake in far northern and northeast
Illinois, and northwest Indiana upper 70s to low 80s still are
plausible, with mid-upper 70s farther west, unless thicker clouds
and showers overspread that area more quickly than currently expected.
Confidence is relatively higher in at least scattered slow moving
showers and isolated to widely scattered thunderstorms spreading
northeastward across the western or northwestern half or so of the
CWA Thursday evening into Friday morning. The overall highest PoPs
in the latest official forecast are in the mid to high chance
range Thursday evening and overnight. If the favored corridor from
the 12z guidance does come to fruition, we`ll need to bump up
these PoPs for the west or northwest half of the CWA. With sub-
marginal deep layer shear, but above to well above normal PWATs
for late September, the main concern will be instances of
localized heavy downpours and road ponding.
How quickly the shower activity dissipates on Friday will
undoubtedly play a role in how warm the temperatures get, and
currently inland portions of Chicago and near and southeast of
I-55 elsewhere have the highest chance to reach the lower 80s.
The latest signs are pointing toward a possible lull later Friday
and into or through Saturday, when PoPs are at a relative minima.
Should this come to pass, then the main story Saturday will be the
warm and fairly humid conditions for this time of year.
While there is still unsurprisingly a considerable amount of
spread in guidance regarding the exact evolution of the western
CONUS trough into next week, there is at least a reasonable
amount of agreement that it will progress eastward into the
central/northern Plains this weekend and potentially stumble into
the Upper Midwest at some point thereafter. The cyclonic flow
around it will serve to advect moisture northward into the Midwest
and maintain an active weather pattern in the region for multiple
days at some point over the second half of this weekend and into
next week.
The latest NBM actually has slight chance to chance PoPs in our
forecast area every day through Tuesday, though whether those
daily precipitation chances will actually materialize will depend
upon finer scale details pertaining to the evolution of the upper-
level trough/low that just can`t be resolved this far out with
much confidence. Given the propensity of closed off upper lows to
move more slowly in reality than modeled at this lead time (and a
bit of a slower trend in the most recent model suite), it wouldn`t
be surprising if higher precip. coverage holds off until early to
mid next week.
Ogorek/Castro
&&
.AVIATION...
For the 00Z TAFs...
Main Concerns:
* Scattered VFR -SHRA lingering into mid evening
* Chance of SHRA and TS across northern Illinois late tonight into
early Wednesday, mainly expected east of RFD
Showers this evening have persisted far longer than expected, but
still are expected to dissipate within the hour, so we elected to
keep them out of the initial TAF group. Once they do eventually
exit, another round of VFR showers and isolated thunderstorms is
possible overnight into the early morning period. These would be
supported by a developing low level jet but may persist even after
the jet begins to dissipate.
At all but the RFD area, light southeast winds are expected to
turn SSW around the time that the overnight showers would be
developing, and then remain from this direction for most of
Wednesday.
Lenning
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.
&&
$$
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Area Forecast Discussion
National Weather Service Marquette MI
826 PM EDT Tue Sep 19 2023
.SHORT TERM...(Through Tonight)
Issued at 334 PM EDT TUE SEP 19 2023
Water vapor imagery and RAP analysis show troffing over western
Canada and eastern Canada with ridging from northern Ontario nnw
into the Arctic. The mid-level ridge does extend across the
International Border, but flow transitions to wnw thru the central
U.S. A shortwave moving ese thru southern WI is aiding shra and a
few tsra in far se WI into northern IL/IN. To the w, very steep mid-
level rates of 8-9C/km are resulting in a little cape for parcels
lifted from above 10kft. Result has been sct sprinkles from high
based ac clouds across portions of northern MN. Closer to home,
marine layer moisture advecting off of Lake MI combined with daytime
heating has led to considerable cu/stratocu development across
central Upper MI today. Temps currently in the mid 60s to lwr 70s F
across the fcst area are not likely to rise much more, if any, for
the rest of the aftn.
The steep mid-level lapse rates to the w do spread e over the fcst
area during the night, but are fcst to be not quite as steep in the
7.5-8C/km range. Nonetheless, this may continue to support some sct
sprinkles spreading into Upper MI, but likely nothing more given the
dry subcloud deck down to around 4-5kft. Meanwhile, continued se
upslope flow of higher dwpt air off of Lake MI into a cooling
central Upper MI should result in a transition of cu/stratocu into
developing low stratus and some fog. At this point, don`t expect
dense fog since there won`t be good radiational cooling to make the
difference btwn land temps and the higher dwpt marine layer air much
more substantial. Although not included in fcst, it`s possible the
moisture depth may become sufficient for some patchy drizzle where
upsloping is maximized. Expect min temps in the mid 40s to mid 50s
F, coolest interior e.
.LONG TERM...(Wednesday through Tuesday)
Issued at 332 PM EDT TUE SEP 19 2023
Key Messages:
-Warming trend continues through work week
-Trajectory of western US trough will determine rain chances late
this week and into the weekend
-Warmer and more dry than normal weather expected next week
Quasi-zonal mid/upper level flow across the northern tier of the
CONUS will become considerably more amplified by mid to late week as
a ridge building into the Gulf of Alaska will force troughing into
the Pacific coastal mountain region, which in turn will force
ridging to build into the Upper Midwest/Upper Great Lakes by the
middle/end of the week. The western US low will eventually shift
eastward by the end of the week into next weekend, possibly
interacting with or becoming captured by troughing over the southern
Canadian Prairies. It is this latter interaction that will have the
biggest implications for sensible weather locally, as considerable
poleward moisture transport is likely to occur in a narrow corridor
to the east of the low center. Whether the forcing and moisture
overlap over the UP to bring bouts of rainfall or whether it stays
to the west remains to be seen.
Significant warm advection with southerly flow at 850mb should lead
to a substantial warming trend beginning Wednesday and continuing
through late week. 850mb temps rising into the upper teens (C) late
Wednesday into the weekend represent values in the 90th to 97.5th
percentile of the NAEFS climatology. Some CAMs bring some weak rain
solutions to portions of the UP for Wednesday, but agreement is
minimal and the forcing is a tug of war between the positive
vorticity advection impulse shortwaves riding the longwave ridging
and the negative vorticity advection from the aforementioned ridging
aloft. Electing to go with a dry solution, but CAMs will bear
continued monitoring for any increasing agreement in precipitation,
perhaps remnant precipitation from a more prominent ridge-riding
shortwave going through the Upper Plains.
Precip chances rise Thursday as a more prominent shortwave not
associated with the main longwave trough over the western US rides
southwesterly flow towards the Great Lakes basin. The shortwave will
be weakening as it arrives in the region, though global
deterministic solutions disagree to what extent the
deamplification occurs. Will keep PoPs somewhat lower at this
time, but some slight chance (15-25%) PoPs are not unreasonable if
the shortwave can maintain enough strength as it arrives in the
area.
Slight chance/chance PoPs (20-40%) return to the forecast Friday
night through the weekend as the longer-wave trough interacts with
troughing over the Canadian Prairie and allows deeper Gulf moisture
to be drawn north toward the Upper Great Lakes. Relatively better
chances (30-40 pct) will be the further west one goes. With lowering
surface pressures to the west, flow will become southeasterly to
easterly and could get fairly breezy by the weekend, with 25 mph
gusts possible. The decreasing southerly component to the low-level
winds and likely increased cloud cover will lead to a downward trend
in the temps by the weekend, although highs will still likely be a
bit above normal, and lows will also probably be above normal due to
the clouds and winds. Expect chance PoPs to linger into early next
week as the Plains trough looks like it finally pushes east into the
Upper Great Lakes. Ultimately, large spread exists in both the
ensembles and deterministic output regarding the progression of
surface features, so not much chance from the NBM is made in the
extended and confidence remains low in the finer details of the
forecast.
Looking into the extended forecast period, by early next week,
the GEFS shows anomalous 500mb heights in excess of 30 dam over
the Hudson Bay with +20 dam height anomaly expected to persist
through the week. This will help contribute to higher than
seasonal temperatures for the remainder of the month and the ridge
will likely act to to suppress precipitation to below normal.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 824 PM EDT TUE SEP 19 2023
VFR conditions will hold at IWD and CMX through the entire TAF
period. Expect low stratus to develop this evening with upsloping
southeasterly winds bringing in cooler dewpoint temps off Lake
Michigan into the cooler interior areas of Upper Michigan. This low
status will bring cigs at SAW down to LIFR tonight, gradually
burning off through the late morning with VFR returning by
tomorrow afternoon.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 332 PM EDT TUE SEP 19 2023
Except for some southeasterly gusts near 25 kt between the Keweenaw
and Isle Royale tonight, winds will remain below 20 kt through this
week. Looking ahead to the weekend, southeast-east gusts of 25-30 kt
may be possible depending on the track of a low pressure tracking
out of the Plains, but it looks like winds should stay sub-gale.
Some slight chances of thunder (15-25%) is possible Friday and over
the weekend, but uncertainty is high.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Rolfson
LONG TERM...GS
AVIATION...Jablonski
MARINE...GS
Area Forecast Discussion
National Weather Service New York NY
1100 PM EDT Tue Sep 19 2023
.SYNOPSIS...
High pressure builds into the region and remains in place through
Friday before shifting offshore. As the high exits, low pressure
developing over the Southeast may produce rain over the weekend.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
No changes for this update as the fcst is on track. A closed
low H5 trough axis shifts east of the region with rising heights
as ridging develops.
As the the high builds closer to the area, clear skies and
lighter winds have begun to allow for efficient radiative
cooling conditions to take place as temps for outlying areas
have fallen. Coastal and urban areas bottom out into the 50s,
and the usual cooler spots well north and west of NYC and the
Long Island Pine Barrens can expect temperatures in the 40s.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
A tranquil and pleasant pattern persists mid to late week with
surface high pressure gradually building in from the west. Aloft,
an upper ridge amplifies over the Upper Great Lakes, with gradual
height increases through the period.
Abundant sunshine prevails both Wednesday and Thursday with
temperatures topping out in the low to mid 70s once again. A
light northwest flow on Wednesday veers northerly into Thursday
as the surface high tracks closer. Largely followed a blend of
NBM and HRRR data for this update.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A mid to upr 1020s high over the area Thu ngt translates
offshore on Fri. Continued dry and cool Thu ngt, then ely
component flow increases on Fri as low pres attempts to develop
off the Carolina coast. Still dry on Fri but increasing clouds
and winds increasing to around 10-20 mph by the end of the day,
particularly at the coasts. Stayed close to the NBM for temps
Thu ngt-Fri.
The models are not in complete agreement with the exact track and
timing of the Southeast low for the weekend, although the data
suggests there will be a sys to track. Due to the model uncertainty,
the blended approach per the NBM was followed over the weekend. If
the low is far enough north per the GFS, Sat could be brisk and
rainy. The ECMWF on the other hand suggests the area will be mainly
dry with the sys too far south. It is possible that a stacked low
remains behind the leading sys, only slowly passing thru the area on
Sun providing another focus for rain, albeit less intense due to a
lack of strong advection. Temps over the weekend will be tied to the
rain. Drier solns should pan out warmer, and wetter solns colder.
Only exception would be if parts of the are warm sector for a period
of time. Based on all of this, a middle of the road approach was
used, and the NBM was followed with local adjustments.
The Mon-Tue evolution of the atmosphere remains highly uncertain
with an upr lvl trof exiting the area. The models have trended dry,
but based on the blended approach, have kept in low pops per the NBM
with the upr lvls uncertain. With an upstream dry airmass to tap
into, it is possible that fair early autumn wx sets up for the
period.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
VFR through the period as high pressure builds over the terminals.
The winds tonight will be out of the NW and mainly at 5 to 10 kt,
with outlying terminals getting under 5 kt. The winds then back
slightly to the WNW Wednesday and mainly settle in at 7-10kt.
Coastal terminals may back a bit more to the WSW Wed afternoon.
....NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No amendments expected.
OUTLOOK FOR 0Z THURSDAY THROUGH SUNDAY...
Wednesday Night - Friday: VFR.
Saturday and Sunday: MVFR or lower likely in rain. E gusts 15-25 kt,
possibly higher at the coastal terminals. Strongest winds at this
time look to be on Saturday.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Southeast swells from distant Hurricane Nigel will begin to have
less and less of an impact as time goes on. Therefore going
forward, sub small craft conditions take place Wednesday
through Thursday night.
Winds and seas gradually increase thru the day on Fri, with a sca
possible on the ocean by the end of the day. A sca appears likely
for most if not all of the waters on Sat. There is a chance for
gales, particularly ern waters and the ocean. A sca is possible
again on Sun, then gradual improvement on Mon.
&&
.HYDROLOGY...
No hydrologic impacts are anticipated through Friday.
Locally heavy rain will be possible over the weekend depending on
the exact track, timing, and intensity of low pres off the coast.
Hydrologic impacts will be possible if the hvy rain scenario
develops.
&&
.TIDES/COASTAL FLOODING...
There is a moderate rip current risk Wed and Thu.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JMC/DR
NEAR TERM...
SHORT TERM...DR
LONG TERM...JMC
AVIATION...JE
MARINE...JMC/DR
HYDROLOGY...JMC/DR
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Shreveport LA
1013 PM CDT Tue Sep 19 2023
...New UPDATE, SHORT TERM...
.UPDATE...
Issued at 954 PM CDT Tue Sep 19 2023
Expanded pops for I-30 counties this evening and down toward I-20
after midnight to include more NE TX, SW AR and LA overnight/Wed.
&&
.SHORT TERM...
(Tonight through Wednesday Night)
Issued at 954 PM CDT Tue Sep 19 2023
Convective push in progress across NE TX and SE OK is about to
edge into our NE TX counties with small elements of mostly middeck
precip. There are some low clouds forming as well of SE OK. The
HRRR is initializing fairly well and does now include more of our
cwa`s real estate and we have updated with the latest in the NBM
giving pops and weather to new areas overnight. Overall, we are
more stable and dense air-wise with a continued decline in
strength for now, but it does look as thought coverage will be
increasing for us. Our sounding only had a PWAT of 0.84in and a
modest little cap at about 7.5kft where winds veer from SW to W.
Lots of mid level dry air to work through should any storms edge
in overhead as well with DCAPE over 1300J/kg, so it is possible we
could see a stout storm as moisture in the midlevels encroaches
from the NW. Aloft we do continue with light W/NW flow up to 30kft
then brisk winds are striping away the anvils. This is why the
radar looks imposing quickly with anvil blow off wetting the mid
levels. No other changes for now, and we will monitor overnight
for additional changes in coverage and perhaps intensity. SPC has
no meso discussion for this activity, but continue a Marginal Risk
for our I-30 and General Risk from Cherokee to Caddo and Columbia
through 7am. /24/
&&
.LONG TERM...
(Thursday through next Monday)
Issued at 246 PM CDT Tue Sep 19 2023
As we begin the long term on Thu, upper ridging will be anchored
across S TX into Central TX as a deep longwave trough will be
positioned from near the Great Lakes, south and east through the
Ohio/Tenn Valleys into the Southeast U.S. Flow across our region
will be mostly westerly to northwesterly as the downstream trough
continues to move eastward into the Appalachians and the upper ridge
to our southwest retrogrades westward into Old Mexico. South
southwesterly low level flow will allow for the return of low level
moisture into our region and disturbances in this upper flow will
provide the necessary forcing for scattered convection across our
northern third on Thu and more areawide by Friday.
Our region appears to be in between disturbances aloft for Saturday
and progs have been hinting at that the last few model runs. For
this reason, have removed rain chances for the day Saturday but
reintroduce pops in earnest Sat Night across our NW half and
areawide on Sunday as the upper flow across the Southern
Plains/Lower Miss Valley becomes difluent in advance of a deep
closed low across the Central Plains. If we can continue to see some
consistency in the medium range progs with this kind of upper level
pattern, it would promise descent rain chances Sunday through at
least Monday of next week before our next frontal boundary arrives
sometime late Monday into Tuesday of next week.
Too early to determine if these periods of thunderstorm chances
either by late weekend or early next week will support a threat for
severe weather but dewpoints and daytime heating would support at
least a marginal wind and/or hail threat across our region during
this timeframe. /13/
&&
.AVIATION...
(00Z TAFS)
Issued at 640 PM CDT Tue Sep 19 2023
For the ArkLaTex terminals, VFR this cycle through the overnight
and much of Wednesday. We may see some convection nudge down the
I-49 corridor of SW AR, possibly into KTXK/KELD by 21Z and may
some showers close to KSHV Wed late aftn. We will see another set
up for a nocturnal push late Thursday and early Friday as a weak
frontal boundary sinks into NE TX. SFC winds on Wed SE/S 5-10KT
w/ gusts to 15-20KT. Light N/NW flow aloft will drive any cells
from N/NW to S/SE generally so thru the wknd until fropa. /24/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 69 94 71 95 / 10 10 10 10
MLU 64 92 67 93 / 0 10 0 10
DEQ 64 86 66 88 / 50 60 30 40
TXK 67 89 68 90 / 20 40 20 20
ELD 64 86 66 88 / 10 20 10 10
TYR 72 94 74 95 / 20 20 10 10
GGG 69 93 70 93 / 20 20 10 10
LFK 68 94 71 95 / 0 10 0 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
SHORT TERM...24
LONG TERM....13
AVIATION...24
Area Forecast Discussion...UPDATED
National Weather Service San Angelo TX
657 PM CDT Tue Sep 19 2023
...New AVIATION...
.SHORT TERM...
(This evening through Wednesday)
Issued at 227 PM CDT Tue Sep 19 2023
The main concern will be the chance for strong to severe
thunderstorms late this afternoon and evening for areas north
of a San Angelo to Brownwood line. Latest CAMs continue to show
a few thunderstorms developing from the Concho Valley north into
the Big Country late this afternoon, with the HRRR the most
aggressive. The airmass across the area this afternoon will
continue to destabilize, with CAPEs near 2000 J/kg and deep layer
shear between 40 and 50 knots. While the better forcing will
remain north into Oklahoma, isolated to widely scattered
convection is possible east of the dryline from the Big Country
south into portions of the Concho Valley after 5 PM, with large
to possibly very large hail and damaging winds the main threats.
However, an isolated tornado cannot be ruled out, primarily for
storms that develop farther north into the Big Country.
Storms that do develop are expected to diminish or move east of
the area by mid to late evening, with dry conditions prevailing
overnight into Wednesday. Unfortunately Wednesday still looks to
be the hottest day of the week, with the ridge axis overhead.
Highs Wednesday afternoon will be mainly in the upper 90s,
although a few locations are expected to reach 100 degrees across
western portions of the Big Country and Concho Valley. Lows
tonight will be in the upper 60s and lower 70s.
&&
.LONG TERM...
(Wednesday night through next Tuesday)
Issued at 135 PM CDT Tue Sep 19 2023
Showers and thunderstorm chances return Thursday across the Big
Country and Concho Valley, as weak upper disturbances move across
the region. Temperatures will not be as hot, with highs in the
lower to mid 90s.
Temperatures Friday into Saturday do warm back into the mid and
upper 90s. Unfortunately the weak cold front previously indicated
Saturday night and Sunday does not appear to make it into the
region, so warmer high temperatures in the lower 90s are
expected Sunday. Isolated showers and thunderstorms still
possible, however, with weak upper disturbances continuing over
the region into next week. Confidence is not high with the
rainfall, however, as upper ridging also builds in.
&&
.AVIATION...
(00Z TAFS)
Issued at 654 PM CDT Tue Sep 19 2023
With a few thunderstorms developing east and southeast into the
Big Country this evening, continuing with a VCTS mention at KABI
from 0030Z to 0230Z. Will monitor radar trends and update if it
looks like any storms may have a direct impact. Farther to the
south and west, a few storms developed over the Permian Basin but
have dissipated. At this point, not expecting any storms to make
a close approach to San Angelo. Generally clear skies and VFR
conditions are expected overnight and during the day Wednesday.
Gusty south winds will continue at KABI through the period, with
gusts 20-25 knots. Gusts of 18-21 knots are expected at KSJT. For
our southern terminals, south winds will be 7-10 knots tonight,
followed by increased wind speeds and gusts by mid-morning
Wednesday into the afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 72 98 74 92 / 30 10 10 40
San Angelo 72 99 73 95 / 10 0 0 20
Junction 68 98 69 96 / 0 0 0 10
Brownwood 69 96 71 93 / 10 10 0 10
Sweetwater 72 99 75 91 / 10 10 10 40
Ozona 69 96 71 93 / 0 0 0 10
Brady 70 96 71 93 / 10 10 0 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...24
LONG TERM....04
AVIATION...19
Area Forecast Discussion
National Weather Service Topeka KS
555 PM CDT Tue Sep 19 2023
...AVIATION UPDATE...
.DISCUSSION...
Issued at 230 PM CDT Tue Sep 19 2023
Key Points:
- Unsettled pattern continues through the weekend with near average
temperatures.
- Potential for severe storms Thursday night through Saturday, but
details still uncertain.
Looking at the large scale pattern, broad zonal flow remains in
place across much of the CONUS. Regionally, water vapor imagery
shows a well-defined shortwave trough over southwest Kansas. WAA
ahead of this feature has resulted in scattered showers and
thunderstorms across eastern Kansas. Most of these storms have
remained weak given below 1000 J/kg of MU CAPE and 20 kts of shear,
though a few have briefly produced small hail. The cloud cover is
helping to keep temperatures in the 70s, with 80s farther west where
skies are mostly clear. As the shortwave progresses across southern
Kansas this PM, expecting scattered showers/storms to persist while
remaining weak in intensity. The shortwave will gradually lift
northeast tonight and tomorrow, with just a small chance for
additional showers across far eastern Kansas.
Flow aloft becomes more southwesterly by Thursday as a large upper
low establishes itself across the western CONUS. Ahead of the main
upper low, several weaker shortwaves will lift through the central
Plains Thursday night and Friday night. Each of these will result in
thunderstorm development, though the exact location will depend on
the position of the dryline to the west and the warm front somewhere
near or north of the area. The main upper low looks to approach
sometime Saturday, with an associated surface low and cold front
pushing eastward. The overall synoptic pattern still looks favorable
for severe weather somewhere in the central Plains, given the strong
upper trough, good moisture advection, and steep mid-level lapse
rates. However there is still a fair amount of spread in the exact
speed and track of the main upper low, partially tied to the
development of a cutoff low over the southeast coast. So we will
need to resolve this track uncertainty some before we get a more
precise idea of the what/where/when of any eventual severe weather.
The upper low will move east of the area by early next week,
resulting in more of a quiet pattern, with temperatures remaining
near or slightly below average.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday)
Issued at 548 PM CDT Tue Sep 19 2023
Shortwave appears to be propagating east of the terminals per the
2230Z water vapor and radar data. There may be an isolated -SHRA
over the next hour or so, but the bigger impact to the terminals
will be stratus advecting in from the south overnight. There is
good consensus among the models and forecast soundings are
bringing it in between 700 and 1000 feet. So will go with IFR
CIGS. Timing is a little tricky as the 21Z RAP has sped up the
moisture advection and arrival of the stratus. Will trend sooner
with the low clouds but use a compromise of the RAP and NAM until
it becomes more obvious. Forecast soundings suggest BKN CIGS
around 3KFT could hold on for TOP and FOE through the afternoon
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION...Reese
AVIATION...Wolters