Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 05/10/20

Area Forecast Discussion...UPDATED

National Weather Service Brownsville TX

 631 PM CDT Sat May 9 2020

.DISCUSSION...Updated for latest aviation discussion below.

&&

.AVIATION...VFR conditions are expected to generally prevail
through the TAF period with perhaps brief reductions to MVFR
ceilings tonight, especially at BRO. Shower and thunderstorm
chances have decreased but elected to keep the mention of a
vicinity shower through the overnight at BRO and HRL. Rain
shower and/or thunderstorm may be possible Sunday afternoon
but will leave out of TAF for now due to lower confidence.
Anticipate light to moderate north-northeasterly winds with
directions then becoming more easterly throughout Sunday.

&&

.PREV DISCUSSION... /issued 418 PM CDT Sat May 9 2020/

UPDATE...Elected to drop the Flash Flood Watch for the rest of
the afternoon as the concern for the potential of flooding has
diminished. Additionally, have lowered the pops down to isolated
to generally scattered levels into tomorrow with short term model
guidance indicating less QPF signal. This is from the result of
the stabilization of the atmosphere in wake of the Mesoscale
convective vortex (MCV) last night with the RAP SPC Mesoanalysis
showing modest instability across portions of the lower to mid-
valley as confirmed in this afternoon`s 18Z BRO sounding. Latest
model guidance also indicates a tongue of some drier air filtering
into the western/northern portions of Deep South Texas as well
into Sunday.

Aviation...Adjusted TAFs for lower potential for showers and
thunderstorm activity. VFR to MVFR conditions generally prevail
through the TAF period with vicinity shower activity and light to
moderate east-northeasterly winds.

Brady/62

PREV DISCUSSION... /issued 252 PM CDT Sat May 9 2020/

SHORT TERM (Now through Sunday Night): Surface low pressure
continues to spin off the lower Texas coast, with showers and
thunderstorms across the adjacent offshore Gulf of Mexico waters. A
couple of weak spokes of mid-level energy swing across Deep South
Texas into this afternoon and again this evening into tonight, and
may be the next best chance of rain development across the coastal
counties, although so far, it has been very quiet. The morning
sounding at BRO showed MUCAPE values topping 1200 J/kg, with PWAT
values at 1.75 inches, but a very stable atmosphere at the surface.
We decided to release a special 18Z sounding to get a newer peek at
the strength of the cap and give the models some new data. The 18Z
run came in with CAPE under 1000, no cap to speak of, PWAT values at
1.65 inches. Somewhat stable or conditionally stable low level, but
anything that does develop could efficiently produce rainfall. We
decided to leave the Flash Flood Watch in effect until 7 PM to
continue the messaging, especially for at risk areas that received
more than 3-5 inches last night.

Have added a Coastal Flood Statement due to elevated surf and
stronger northeasterly winds creating narrow beaches and potentially
pushing South Bay water across portions of HWY 4 west of Boca Chica
Village. High tide was early this morning and low tide occurs near
11 PM. Webcams were showing decent beach runup and wet sand near the
dunes.

Temperatures gradually warm through Sunday with southeasterly winds
returning as high pressure builds across the Gulf of Mexico. Models
continue to show the chance of rain returning inland for Sunday
afternoon and early evening. The next vort at 500mb swings by just
south of the border into Sunday afternoon, keeping the best rain
chances along the RGV, with PWAT values rising back toward 1.6-1.8
inches, and slightly drier air aloft.

LONG TERM (Monday through Saturday): As broad high pressure slowly
moves off to the east and claims the eastern CONUS through the
workweek, southeasterly winds will persist across Deep South Texas
and the RGV through the long term period. A couple of embedded short
waves will be advected over Deep South Texas in the nearly zonal
flow aloft throughout the week. The first short wave approaches on
Monday and pushes northeastward on Tuesday, bringing rain chances
Monday through Tuesday. The bulk of the divergence aloft associated
with the short wave on Tuesday will be concentrated further north
over south central Texas, so the greater rain/thunderstorm chances
will be concentrated in that region, but have kept slight chance
PoPs since the divergence aloft could be enough to trigger some
convection over Deep South Texas and the RGV. There will be a
warming trend throughout the long term period into the weekend.
Monday`s highs will be in the 80s and each day the highs will
increase slightly until the weekend when the highs are generally in
the mid to upper 90s. The next best chance for rain will be Friday
into the weekend as another short wave passes through. However,
model solutions diverge late next week, so confidence is low on the
timing of the PoPs, as well as on the temperatures for the weekend.
For now, have trended toward the model blends which tend to favor
the warmer ECM`s solution.

MARINE: Now through Sunday Night...Coastal low pressure slowly
works further east across the Gulf of Mexico as high pressure
enters across the northern Gulf. Moderate to strong northeast
winds have continued into the afternoon and are expected to begin
to diminish into this evening, allowing seas to diminish into
Sunday. Winds turn more southeasterly on Sunday as high pressure
settles further south.

Monday through Saturday...Southeast winds will persist through
next week as a broad region of high pressure parks over the
eastern Gulf. Winds will increase each afternoon and small craft
will likely need to exercise caution for much of the week. Wave
heights will start off on Monday around 2 to 4 feet and increase
to 3 to 5 for the latter half of the week. There will be a slight
chance for showers and thunderstorms Monday and Tuesday.

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Small Craft Advisory until midnight CDT tonight for GMZ150-155-
     170-175.

&&

$$

This product is also available on the web at:
HTTP://WEATHER.GOV/RGV

Aviation...Brady/62



Area Forecast Discussion

National Weather Service Grand Junction CO

 535 PM MDT Sat May 9 2020

.SHORT TERM...(Tonight through Sunday night)
Issued at 146 PM MDT Sat May 9 2020

Northwest flow aloft is keeping the weather quiet and pleasant. A
few shortwaves embedded within this flow have clipped portions of
northern Colorado ushering in cooler temperatures, so we are near
normal again today. The bulk of the available moisture is east of
the Divide so no precipitation is expected from these waves. In
passing the winds have been enhanced by the slightly tighter
pressure gradient, and deep mixing will allow gusty winds to reach
the surface. Critical fire weather conditions have already
started across the lower elevations of southwest Colorado, and
expect that to continue through the evening.

A weak sub-tropical wave located over the Baja will track to the
north-northeast tonight. This wave will help advect moisture into
the region for the next couple of days. By tomorrow the wave reaches
Utah and begins to encounter the northwest flow aloft. This will
cause the wave to progress eastward over the forecast area, and it
also appears to cause the wave to slightly strengthen. The models
still agree that the moisture might not make it into our area by
peak heating tomorrow. There may be enough for isolated showers and
storms mainly in the higher elevations, but those chances are low.
Luckily fuels at those elevations are not critical yet. Although if
a storm were to reach the valleys it could be concern for new fire
starts. Something to pay attention to if convection materializes.
The most likely zone for convective development will remain to our
west and south in the afternoon, but that activity will drift into
the area in the late afternoon and evening hours. The initial surge
of moisture will be in the midlevels therefore bases are expected to
be fairly high. As a result most of the precipitation will struggle
to reach the ground and virga enhanced wind gusts will be possible.
The latest NAM and HRRR show pockets of strong winds associated with
these showers moving into our area, and that is supported by DCAPE
upwards of 1000 J/kg evident in the soundings. Elevated fire danger
is possible tomorrow afternoon as winds speeds get close to criteria.
Localized red flag conditions can not be ruled out especially with
gusty outflow or virga.

During the overnight the wave tracks over the forecast area, and the
associated forcing will allow showers and storms to increase in
coverage. Instability should be on the decrease Sunday night, but
there may be enough for a few storms embedded within the showers,
especially in southeast Utah and southwest Colorado.

.LONG TERM...(Monday through Saturday)
Issued at 146 PM MDT Sat May 9 2020

Precipitable water values are on track to peak across the region
late Monday morning/early afternoon as a midlevel shortwave
impacts the area. Readings are expected to be between 0.55 to
0.70 inches...or 140 to 180% of the climatological normal for mid
May. Bufkit soundings across west-central Colorado show the
saturation of the mid and lower levels during this timeframe as a
result. Isolated shower coverage will increase to become scattered
to numerous throughout the day. The higher terrain along the
Continental Divide will be favored for the best shower coverage
and potential for wetting rains, due in part to the shortwave
trough trekking right along that region on Monday. Isolated to
scattered thunderstorms will also be possible throughout the day
as MLCAPE nears 1000 J/kg. The convection potential will need to
be monitored over the coming shifts, particularly since cloud
cover Monday morning could inhibit instability.

The shortwave will slide east into the Plains Monday evening with
showers gradually tapering off from west to east. Synoptic flow
over eastern Utah and western Colorado will become quasi-zonal
Tuesday and Wednesday as an upper level low spins off the Pacific
Northwest. This will result in generally dry conditions over the
forecast area, though entrained moisture in the flow could see
isolated orographic showers develop each afternoon. Temperatures
will remain above normal with readings only fluctuating slightly
each day. Early Thursday will see the Pacific low push inland with
upper level flow becoming southwesterly over our region as a
result. This feature will trek across the Northern Rockies on
Friday, potentially brushing the northern tier of the forecast
area Friday afternoon and evening. Extended models disagree on the
progression and depth of this now open wave trough as we head into
the weekend. Regardless, slightly cooler and unsettled conditions
are becoming likely to end the long term period.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 518 PM MDT Sat May 9 2020

VFR will dominate at all terminals through the evening. Expect
gusty winds in the south to diminish after 1z as solar heating and
mixing cease. After a clear night, VFR will dominate at all
terminals on Sunday. Isolated mountain showers could develop in
the San Juans late in the evening.

&&

.FIRE WEATHER...
Issued at 146 PM MDT Sat May 9 2020

Dry weather will continue today as deep mixing and a passing
system to our north bring some gusty winds to the surface this
afternoon. Red Flag criteria will occur this afternoon thanks to
those winds, dry conditions, and critical fuels. As such, Red
Flag Warnings remain in effect across portions of southwest
Colorado this afternoon and evening for zone 207 below 8000 feet
and zone 295 below 9500 feet. Localized Red Flag conditions are
possible tomorrow afternoon along with gusty outflow or virga from
high-based showers mainly across southeast Utah and southwest
Colorado. A few dry thunderstorms could reach the lower valleys in
these areas.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...
CO...Red Flag Warning until 9 PM MDT this evening for COZ207-295.

UT...None.
&&

$$

SHORT TERM...KJS
LONG TERM...MMS
AVIATION...MAC
FIRE WEATHER...TGJT




Area Forecast Discussion

National Weather Service Green Bay WI

 1048 PM CDT Sat May 9 2020

Updated aviation portion for 06Z TAF issuance

.SHORT TERM...Tonight and Sunday
Issued at 245 PM CDT Sat May 9 2020

The latest RAP analysis and satellite/radar imagery show a tightly
wound and compact shortwave moving southeast over the Dakotas
early this afternoon. Mid-level clouds and light precip are already
pushing into far western Wisconsin, but is moving into a very dry
airmass with humidities in the 15 to 25 pct range at most
locations away from Lake Michigan. Therefore think that some of
this precip will dry up or remain virga as it moves into north-
central WI later this afternoon. Looking further upstream, precip
changes over to snow over north-central Minnesota and North
Dakota. As this storm system moves across the region, snowfall
accumulations is the main forecast concern.

Tonight...The compact yet potent low pressure system will track
across southern Wisconsin. The lead band of light precip will lead
to moistening of the atmosphere at the start of the evening over
north-central WI. As precip rates increase due to strengthening
mid-level fgen on the nose of a 30-40 low level jet, precip will
have greater chances of reaching the ground through the evening.
The dry feed of air from northeast winds will lead to evaporative
cooling and models show critical thickness collapsing (precip
changing over to snow) by mid to late evening along and north of
the Hwy 29 corridor from Wausau to Green Bay. In this corridor,
forecast snow accumulations remain expected to be the highest,
peaking in the 2-3 inch range, locally up to 4 inches in Lincoln,
Langlade, and northern Marathon counties. Snow accumulations
should trail off further east as the boundary layer will have a
harder time cooling down. Some snow accumulations (up to an inch)
will be possible south of Hwy 29 after midnight. After adjusting
temps, precip amounts, and snow ratios, the forecast turned out
pretty similar to the previous forecast so no adjustments will be
made to the Winter Weather Advisory. Given the narrow nature of
this band, however, wouldn`t be surprised if a thin ribbon of 4-5
inches of snow materialized. Pavement temps are forecast to remain
above freezing tonight. But think some slippery and/or snow
covered roads are possible where snowfall rates will be the
highest. Lows ranging from the upper 20s to mid 30s.

Sunday...Light snow will likely continue through the morning over
parts of central to east-central Wisconsin. Additional amounts of
a half inch to an inch look possible, though will have a tough
time accumulating on roads due to the high sun angle. Most precip
should end by late morning to early afternoon as the surface low
tracks over southern Lake Michigan and southern Lower Michigan.
Expected plenty of clouds to linger into the afternoon with gusty
northeast to north winds make it a blustery and damp day. Highs
ranging from the low to mid 40s.

.LONG TERM...Sunday Night Through Saturday
Issued at 245 PM CDT Sat May 9 2020

The forecast focus will remain on potential frost/freeze and fire
weather concerns Monday and Tuesday, then a return to a milder
and wetter pattern for the mid to late part of the week.

A short-wave trough and surface low will be exiting to our east
Sunday evening, leaving dry conditions over the forecast area.
After a cloudy evening, expect to see clearing arrive from from
northwest to southeast overnight into early Monday. The timing of
the clearing will determine how cold we get, and where eventual
frost/freeze headlines need to be issued. Right now, it appears
the best chance of hard freeze will occur northwest of the Fox
Valley/lakeshore areas. Skies will become sunny on Monday, with
cool highs in the upper 40s to middle 50s. Deep mixing will allow
dry air aloft to reach the surface, leading to very low dew points
and relative humidity, especially in the sandy soil regions.

A weak cold front is expected to move through the region Monday
night, but skies will remain clear to partly cloudy. Another hard
freeze looks like a good bet northwest of the Fox Valley/lakeshore
areas Tuesday morning. Expect a slight moderation in temperatures
on Tuesday, with highs in the 50s, and another day of very low
relative humidity in the sandy soil regions. Dry conditions should
persist through Tuesday night, but low temperatures should not be
as cold due to WAA and increasing mid/high clouds late.

Strong return flow is expected to develop Wednesday into Wednesday
night, as the surface high shifts east and a 30-40 knot low-level
jet develops. This will bring a swath of showers through the
forecast area. A warm front will move into southern, or perhaps
central WI by Thursday morning, followed by low pressure tracking
E-NE along the boundary on Thursday and Thursday night. The track
of this low will determine how far north additional precipitation
gets, but the best bet for showers and a few thunderstorms should
be over our southern or southeast counties.
&&

.AVIATION...for 06Z TAF Issuance
Issued at 1048 PM CDT Sat May 9 2020

VFR/MVFR ceilings are in place at most of the TAF sites to being
the TAF period. The exception is under a band of light rain
showers stretching across north-central WI, where ceilings have
been lowering to MVFR. Rain showers will likely tranistion to
to mainly snow late this evening and then continue through the
night. Lowest visibility is expected across CWA/AUW, where the
heaviest band of snow is expected to set up. Some light
accumulations are possible in those area; however, pavement
temperatures are expected to remain above freezing. This may still
end up leading to slushy roads/runways overnight across central
Wisconsin. Steadily improving conditions can be expected for
the rest of the TAF period Sunday into Sunday evening.
&&

.FIRE WEATHER...
Issued at 245 PM CDT Sat May 9 2020

After a break on Sunday, elevated fire weather conditions are
expected to return on Monday and Tuesday. Relative humidities
should drop into the 15 to 25 percent range in the sandy soil
regions both days, but winds should only be moderate from the
west-northwest, with gusts to 15 to 20 mph.
&&

.GRB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 8 AM CDT Sunday for WIZ018>020-030-
031.
&&

$$

SHORT TERM.....MPC
LONG TERM......Kieckbusch
AVIATION.......Cooley
FIRE WEATHER...Kieckbusch




Area Forecast Discussion

National Weather Service Grand Rapids MI

 839 PM EDT Sat May 9 2020

LATEST UPDATE...
Update

.SYNOPSIS...
Issued at 315 PM EDT Sat May 9 2020

- Clipper with cold rain and snow Sunday

- Another Freeze Monday night

- Wet Pattern after Mid-week

&&

.UPDATE...
Issued at 840 PM EDT Sat May 9 2020

Overall our forecast looks fine. However, it seems to me we have a
greater risk for convective shower between midnight and 3 am (or
so) near I-96 (as far south as maybe Holland).

I have noted from numerous runs of the RAP, HRRR and SREF (SPC)
we have a 35 to 50 knot low level jet aimed at the Grand Haven to
Muskegon area between midnight and 3 am. The moisture transport
vectors are aimed at the same area too. While the instability is
not all that great the sounding from the models are saturated from
5000 ft to 20000 ft in that area. The lapse rate from 850 to 500
mb is about 7.0C at that time. I believe we will see showers, some
briefly heavy. This is shown by the all of the hi resolution
models so I do believe that will more than overcome any dry layer
between 5000 ft and the ground. It do not believe this will
impact ares near and south of I-94 but it will impact from MKG to
GRR. I increased the chance of rain during that time farther
south.



&&

.DISCUSSION...(This evening through next Saturday)
Issued at 315 PM EDT Sat May 9 2020

- Clipper with cold rain and snow Sunday

Looks like a dreary Mother`s Day with cold rain by the afternoon
and some wet snow mixing in late in the afternoon and evening.
CLouds and precip should hold temperatures down into the 40s
across much of the forecast area. No impacts expected for travel
as wet snow on the back side of the departing low should not be
able to stick to paved surfaces even up north.

Steep lapse rates and cold atmosphere means any updrafts could
produce small hail tomorrow afternoon, with the best chance of
that across southern zones where instability is greatest, although
still marginal at best.

- Another Freeze Monday night

The next arctic surface high moves in on Monday and sets up a
better radiational cooling night than last night, although the
airmass isn`t quite as cold. We still should get down below
freezing with lows in the upper 20s most places. The high hangs on
for Tuesday night and frost and freezing temperatures are possible
again Wednesday morning.

- Wet Pattern after Mid-week

The amplified pattern of a deep trough across the northeast CONUS
through mid-week becomes more zonal with deep moisture return into
the Ohio Valley and Great Lakes after Wednesday and into next
weekend. There is heavy rain potential as surfaces waves move
along a wavering frontal boundary. We could be dealing with an
inch or more of rain across Lower Michigan late Wednesday into
Friday with a second wave coming later in the weekend, but
indications are that it may be further south across the Ohio
Valley.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 731 PM EDT Sat May 9 2020

It will start out tonight rather quiet but it will not stay that
way. A fairly vigorous developing storm system will spread
precipitation, gusty winds,and low ceilings across the TAF sites
by Sunday morning.

The system warm front, aided by a 50 knot low level jet aimed at
MKG by 06z, is likely to cause some showers for a few hours, but
at that point ceiling should be around 5000 ft agl and I do not
believe at this time the showers will be heavy enough to lower
visibilities below 6 miles, but it is not out of the question that
there could be a few minutes with a moderate to heavy rain shower
at any of our TAF sites in the between 06z and 10z. The warm
front will also lead to low level wind shear, winds could be as
high as 50 knots between 3000 ft and 5000 ft agl in the 08z to 12z
time frame.

Most of the rain will be during the daylight hours of Sunday as
the system moves through. instability increases in the I-69 area
by 18z or so. Do not be surprised by thunderstorms with brief
very heavy rain (IFR visibility briefly), small hail and gusty
winds.

There will be a period of MVFR/IFR cigs from late morning into the
late afternoon as the system deepens while it is moving through
the area. The heavier and more persistent precipitation will be
just north of I-96. It would not be out of the question for the
precipitation to change to snow before it ends just north of MKG.

It will turn rather windy by late afternoon, once the cold air
comes in behind the cold front trailing the system. Skies should
clear by 06z or so.


&&

.MARINE...
Issued at 315 PM EDT Sat May 9 2020

The Small Craft Advisory will be dropped soon as winds and waves
are decreasing this afternoon. We have issued a Gale Watch for
south of Whitehall Sunday afternoon into Monday as we expect
strong north flow developing with gusts to 35 knots on the back
side of the clipper coming though tomorrow. A Coastal Flood
Advisory is also issued for this stretch of coast.


&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Lakeshore Flood Advisory from 2 PM Sunday to 2 PM EDT Monday for
     MIZ050-056-064-071.

LM...Gale Watch from Sunday afternoon through late Sunday night for
     LMZ844>847.

&&

$$

UPDATE...WDM
SYNOPSIS...Ostuno
DISCUSSION...Ostuno
AVIATION...WDM
MARINE...Ostuno




Area Forecast Discussion...UPDATED

National Weather Service Twin Cities/Chanhassen MN

 742 PM CDT Sat May 9 2020

.UPDATE...
Issued at 651 PM CDT Sat May 9 2020

Updated for 00z aviation discussion below.

&&

.SHORT TERM...(This evening through Sunday night)
Issued at 238 PM CDT Sat May 9 2020

Water vapor imagery this afternoon shows a compact and fairly
intense shortwave trough dropping southeast through the eastern
Dakotas. RAP PV analysis shows the anomaly down around 500 mb with
this feature, which is definitely helping to cool and saturate the
column while promoting a strong band of upper-level divergence and
frontogenesis. The system is moving quickly, and will bring
precipitation across the area for roughly a 6 hour window from
late afternoon into the early part of the overnight hours. The
best chance for precipitation to change to snow and accumulate
still looks to be north of I-94 where an inch or two is still
possible (the Twin Cities metro area will likely see little if any
accumulation). We could have a few rain/snow showers around on
Sunday with some lingering cyclonic flow and decent lapse rate,
but at this point decided to leave them out with no real consensus
on location (and didn`t want to blanket the entire area with 20
PoPs). Cold advection will persist into Sunday night, keeping
clouds around for a while, although we should see enough
subsidence by late Sunday night to clear things out from northwest
to southeast.

.LONG TERM...(Monday through Saturday)
Issued at 238 PM CDT Sat May 9 2020

The large scale pattern looks to quickly de-amplify during the
first part of the week, with things becoming zonal and looking to
stay that way through the balance of the week. That will result in
moderating temperatures with much warmer (near to a bit above
normal) weather by the middle to latter half of the week. With the
steering flow becoming zonal, we`ll see a few quick moving
shortwaves ripple through the flow and bring some chances for
precipitation. Unfortunately, as is typically the case in such a
pattern, there is some disagreement in the model guidance on the
timing of things, which increases farther out into the forecast
period. So, the consensus forecast will include longer periods of
lower PoPs than what reality will eventually bring, but we should
be able to refine the precipitation chances into smaller windows
of time as things get closer. High pressure will keep things dry
Monday and Tuesday, with low RHs each day causing some fire
weather concerns again, although wind speeds should be a limited
factor. Return flow accompanied by decent moisture return looks to
bring a good chance for showers across the area Wednesday. After
that we`ll have several weak shortwaves move east through the
zonal flow bringing periodic shower chances, along with some
possibility of thunder as instability works its way back into the
region. However, at this point no significant systems are expected
through the period.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 651 PM CDT Sat May 9 2020

MVFR ceilings into tomorrow for all sites except AXN which should
go VFR later this evening. There will be a break in the rain this
evening before the wrap around moisture moves in and light rain,
possibly with some snow mixed in at times, will spread back in by
midnight. Ceilings at EAU may go IFR for a couple of hours around
01z, before rising back to MVFR again. All terminals go VFR by
daybreak. The precipitation will end from north to south
overnight. Winds NNE at 10 kts at the start of the period for
AXN, RWF, STC and MKT will quickly back to NNW with gusts up to
20-30 kts. MSP, RNH and EAU will hold onto the NNE winds for a few
hours longer. Tomorrow ceilings will be between 3000 and 6000
feet with overcast or broken skies.


KMSP...MVFR conditions to start the period will continue until
around 08z when the ceilings rise to VFR. There will be a break in
the rain this evening, but there may be some drizzle. The wrap
around precipitation will move back over the terminal from 04Z to
08Z. There could be some snow mixed in but left out of TAF as it
won`t be impactful. Broken or overcast skies will persist
through the day with ceilings between 3000 and 6000 feet. Winds
will be NE around 10 kts to start then quickly back to NNW with
gusts up to 23 KTS this evening. After midnight the wind becomes
more NW around 12 kts through the morning before rising to 15 kts
with gusts up to 25 kts afternoon. Tomorrow evening the clouds
will scatter out.


/OUTLOOK FOR KMSP/
MON...VFR. Wind NW 5-10 kts
TUE...VFR. Wind NW 5 kts.
Wed...VFR. Chance of -RA. Wind SE 5-10 kts.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
&&

$$

UPDATE...CEO
SHORT TERM...
LONG TERM...
AVIATION...CEO



Area Forecast Discussion

National Weather Service San Diego CA

 349 PM PDT Sat May 9 2020

.SYNOPSIS...
A weak disturbance will bring isolated showers over San Diego County
coast and valleys and isolated thunderstorms over the mountains,
through this evening. Otherwise, cooler weather and a stronger
marine layer presence into early next week, with strong westerly
winds over the mountains and deserts and more persistent cloud cover
west of the mountains. It will be warmer again by next weekend.

&&

.QUICK UPDATE...

Isolated showers are occurring over San Diego County
(coast/valleys/mountains) and have updated the forecast to reflect
this. Also, isolated thunderstorms still possible through 10 pm over
the mountains. Looking ahead to tomorrow afternoon/evening, the HRRR
is showing potential for convection over the mountains again, so we
may need to add low pops then, although other indications are that
there will be too much flow aloft and not enough
instability/forcing. Will take another look at that later this
evening. No other changes at this time. Previous discussion remains
in place below.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

A few showers were occurring, mainly near Pt. Loma, and areas of
coastal stratus continued early this afternoon. The cooling trend
was continuing, including in the desert where Palm Springs was
"only" 100 at 1 PM, and beach locations were still in the mid to
upper 60s. A few thunderstorms had developed in northern Baja
California, mainly over the mountains, and there is a small chance
that one of these thunderstorms could stray north of the border.
Most areas that receive any precipitation will just have brief light
rain as a strong dry layer between around 850 MB separated the
moisture aloft around 600 MB and the marine layer.

The strong ridge from earlier this week is flattening as low
pressure expands off the West Coast today. The trough will prevail
most of next week, though it will not be particularly strong at any
one point. This will result in cooler weather, especially west of
the mountains with the deeper marine layer, and the MSLP gradients
and stronger thermal gradients between the valleys and the deserts
will result in gusty winds at times in the mountains and deserts.
The marine layer will be deep enough that some light drizzle or even
light showers could occur at times from the mountain slopes west to
the coast, with around Wednesday being the most likely as a
shortwave could interact with the marine layer moisture. If any
measurable precipitation occurs, it would be just a few hundredths
of an inch, as nearly all GEFS and ECMWF ensemble members show. With
the cooler air mass in place, temperatures will be 5-10 deg F below
normal by Tue/Wed. Some model/ensemble solutions show the trough
shifting east of the area by next weekend with some ridging over
California, and with that solution, some warming will return around
next Fri/Sat.

&&

.AVIATION...
092030Z...Coast/Valleys...Low clouds with bases 1200-1500 FT MSL and
tops to 2000 ft MSL will continue to impact the coast this
afternoon. BKN-OVC cigs likely vcnty KSAN and KCRQ, moving into KSNA
between 00Z and 04Z Sun. Bases and tops will likely lift overnight
as the clouds spread inland, possibly reaching KONT by 10Z and KSBD
by 12Z Sun. Vis will be mostly unrestricted except where clouds and
terrain intersect, obscuring higher terrain. Inland clearing
expected 16Z-17Z Sun and partial clearing at the coast 17Z-20Z.

Mountains/Deserts...A few high clouds at/above 20,000 ft MSL through
the period, with unrestricted visibility. There is a slight chance
of an isolated thunderstorm this afternoon/evening, primarily for
San Diego and Riverside County Mountains, though confidence is low.

&&

.MARINE...
Onshore flow will strengthen from Wednesday onward, when gusts may
approach 20 kts in the outer waters. Otherwise, no hazardous marine
conditions are expected through Wednesday.

&&

.BEACHES...
An increasing south-southwest swell from 200 degrees, with a period
of 16 to 18 seconds, will generate elevated surf at area beaches
beginning Sunday. Surf will be highest on south and southwest-facing
beaches, especially in Orange County where sets to 6 FT will be
likely. Rip current risk will be high.

&&

.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

QUICK UPDATE...Brotherton
PUBLIC...Maxwell
AVIATION/MARINE/BEACHES...PG