Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/10/19
Area Forecast Discussion
National Weather Service La Crosse WI
1055 PM CDT Sun Jun 9 2019
.SHORT TERM...(Tonight and Monday)
Issued at 200 PM CDT Sun Jun 9 2019
Line of convection expected to develop along/ahead of cold front,
fueled partially by a clear slot where +500 J/kg of SBCAPE has
developed, roughly north-south from western WI (through LSE) into
eastern northeast IA in the next hour or two. RAP soundings point to
very skinny CAPE - enough for some rumbles of thunder, but probably
not much else. This activity looks to clear central WI by evening.
Scattered showers behind this line, associated with parent upper
level shortwave. CAMs don`t hang onto this activity very long into
the evening - spotty at best.
Monday, weak high pressure builds across the south while some hints
of a ripple or two in the mid/upper levels moving across northern
parts of the region. Much of the saturation clears tonight with the
passage of the main shortwave trough, but some hints in a few of the
models that there could be some RH to work with. Low/mid level lapse
rates fairly hefty for Monday with some CAPE (although rather
skinny) for any potential shower/storm to act on. Some hints in the
CAMS models along with NAM/GFS that some shower/storms could spark,
mostly north of I-94 and favored in the evening. Saturation a bit
better in those areas. Given the forcing, at least some small pops
are warranted across the north for now - but if better saturation
can be found, the isolated pcpn threat could expand southward.
.LONG TERM...(Tuesday through Sunday)
Issued at 200 PM CDT Sun Jun 9 2019
With the passage of the upper level shortwave trough today,
northwest flow looks to settle in for much of the new week. The
result is a much cooler weather pattern compared to the past few
days, and somewhat active.
1) Temperatures: say goodbye to the summery warmth of last Fri and
Sat and hello to temps one might expect for spring. 850 mb temps
will fall back into the single digits, with both the GFS and EC
dropping in the coldest air on Thu (post a shortwave trough - NAEFS
anomalies around -1 850mb temps). The EC suggests some shortwave
ridging/zonal flow by the weekend with moderating temps, but the GFS
hold firms to cool northwest conditions. Overall, highs will be in
the 60s to 70s with 40s/50s for lows.
2) Pcpn chances: with northwest flow will come occasional shortwave
troughs and accompanying shower/storm chances. Models currently
favoring Tue night/Wed with a good shot for rain, sliding a
shortwave trough across the northern plains and through the local
area. Agreement a bit more sketchy after that. Severe threat looks
low given the current wx setup, but there will be some instability
and shear to play with from time to time, so a few storms remain
possible - although likely leaning on a more shower dominant regime.
The upcoming week will feel a lot more like the spring we missed out
on, rather then the early part of summer.
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1055 PM CDT Sun Jun 9 2019
High pressure will build in from the west overnight behind a
departing cold front pushing into eastern WI. The resultant
pressure gradient is relaxing overhead, so gusty surface winds
are subsiding across the area. While llws criteria won`t be met,
it`s worth noting that NW winds will increase rapidly with height
through the rest of tonight...from under 10 knots at the surface
to around 25-35 kts between 1000-3000 ft AGL. As daytime mixing
develops on Monday, NW surface winds will become gusty again by
late morning through the afternoon with gusts approaching 25 kts.
Winds diminish and back to the SW in the evening. Clearing skies
the rest of tonight will give way to perhaps few to sct fair
weather cumulus Monday afternoon. Some guidance hints at a weak
disturbance bringing a few showers into the area Monday evening,
but confidence in these impacting the TAF sites is rather low at
Area Forecast Discussion
National Weather Service Wilmington NC
943 PM EDT Sun Jun 9 2019
A weak front lingering over the Carolinas will lift north
tonight into Monday. Unsettled weather will continue through
mid week with the possibility of localized flooding. May see a
brief break, mainly inland, on Tuesday as cold front drops
south. Drier high pressure will build in behind a second cold
front late Thursday into Friday with a sunny and drier start to
.NEAR TERM /THROUGH MONDAY NIGHT/...
As of 945 PM Sunday...Expanding arc of showers and t-storms has
pushed as far as east as Georgetown, Marion, and Dillon this
evening. The line should slow its eastward progress and weaken
over the next couple of hours. Although scattered showers can`t
be ruled out across the interior portions of South Carolina
after midnight, ongoing activity should the biggest event of
the night here. Attention will then shift offshore where radar
is already picking up showers 50-100 miles east of Charleston.
The HRRR appears reasonable showing this activity intensifying
as it streaks northward toward Cape Fear after midnight. Some of
the recent HRRR runs indicate streaks of 2-3 inches of rain
possible late tonight, although my forecast has areal averages
closer to 1/3rd of an inch in the Southport/Wilmington area.
I`ve bumped overnight PoPs up to 60-70 percent for Brunswick and
New Hanover counties. No other significant changes have been
made to the forecast. Discussion from 730 PM follows...
Shower and thunderstorm activity has been a little less
widespread today than yesterday, focused for the past several
hours on a line from Conway and Marion north up through
Fayetteville. A larger area of storms extending in an arc from
Charleston through Columbia is moving northward and promises
another rainy evening for the interior Pee Dee region of South
Carolina. Along the coast skies are partly cloudy with very few
showers noted at the current time.
Deep southerly flow with precipitable water values hovering
around two inches will continue overnight. Trying to time subtle
upper level disturbances within the messy convective pattern
across FL/GA/SC is difficult, but it appears a lull in
convection may develop late this evening once the current wave
of storms entering the Pee Dee region moves north. Then look for
scattered showers and t-storms to redevelop along the coast.
Forecast PoPs range from 80 percent (mainly this evening) for
the Pee Dee to around 50 percent along the coast (mainly after
midnight). No significant changes have been made to forecast
winds or temperatures. Discussion from 300 PM follows...
Main concern through Monday night includes slow moving thunder
showers that could bring potential for localized flooding.
Latest upper level analysis and water vapor imagery show an upper
level low pressure system over the southeast with plenty of moisture
rotating into the Cape Fear region. Latest model profiles show a
very moist atmosphere along a stationary front portioned through the
coastal plain region, which will bring chances for rainfall today
through Monday night. Isolated thunderstorms are possible with a
few lightning strikes and a remote chance for a strong wind gust at
times, but main concern with the abundant moisture and little to no
wind aloft is slow moving heavy rain producing storms. Storm motions
are a bit faster based on radar observations today, but minor
flooding is possible, especially for low lying streams or poor
drainage areas in Wilmington and surrounding communities.
Latest model projections depict a break in the rain action this
afternoon into the early evening before chances again late tonight
into overnight. Additional chances for widespread rainfall Monday
late morning into the afternoon hours.
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
As of 300 PM Sunday...A cold front will drop south and east on
Tues but will get hung up near or just south of area as wave of low
pressure develops along it. The big question is, how far south
will the front make it before stalling. GFS and NAM are most
aggressive with southern push of front with about a 10 degree
drop in dewpoint temps as far south as Myrtle Beach. ECMWF shows
drying, but more in the way of a 5 degree drop in dewpoints.
Either way, expect drier air to make it into the area with
decreasing chc of rain, especially inland toward I-95 corridor.
FLO and LBT sounding and moisture profiles just show some
lingering moisture between 4 and 7 k ft but overall expect some
sunshine through Tues aftn inland. As you head closer to the
coast, especially down toward the Grand Strand area, expect
greater amount of clouds and potential for some pcp. Temps
should be right near 80 for highs on Tues.
This will be shortlived as moisture deepens through the column
Tues night as low pressure rides up the Southeast coast. Expect
clouds to spread back north and increasing chc of showers and
thunderstorms heading into Wed. Low temps Tues night will range
from near 70 along the SC coast to low 60s inland.
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
As of 300 PM Sunday...Weak wave of low pressure will track up
along lingering front located along the Southeast coast on Wed,
as mid to upper trough reaching down from the Upper Great Lakes
helps guide it and pushes system off shore by Thurs. With
relatively cooler and drier high pressure inland and
front/trough along the coast, it resembles more of wedge-like
pattern. Therefore, expect best chc of thunderstorms over the
coastal plain and off shore on Wed, where pcp water values will
still be up near 2 inches.
As the mid to upper trough moves farther east, it will push
another cold front through Thurs night. Some lingering moisture
ahead of this front will maintain a chc of pcp, but a deeper
westerly flow will develop veering around to the N-NW by Thurs
night as front crosses the area. Dry high pressure will build
down behind this front Thurs night into Fri finally bringing a
change of air mass and return of sunshine to the Coastal
Carolinas. Aside from an isolated shwr or two, expect a
basically rain free period with temps running near or below
normal for Fri and Sat. High pressure will move off the coast
Sat night into Sun with a return of shwrs/tstms Sun aftn and
warmer and more humid weather.
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
As of 0z...More of the same this TAF period, with upper trough over
the southeast and deep southerly flow across the area. A weak front
that was across the area has moved off the the NW, with a cold front
approaching from the west at end of TAF period. Mostly cloudy skies with
predominantly MVFR ceilings overnight across the area, with
brief VFR possible. Forecasting mostly VFR tomorrow, but could
see a return to MVFR in the afternoon. Scattered showers with
isolated thunderstorms possible overnight, with greater coverage
in precipitation returning tomorrow afternoon. South winds
continue to prevail, sustained around 10kts tomorrow afternoon
with gusts up to 20kt possible at coastal sites.
Extended Outlook...Scattered to numerous convection will become the
mainstay thru early Thursday. Looking at MVFR/IFR conditions
associated with the pcpn, cloudiness and occasionally night-time
fog. Will see periodic VFR conditions outside of the pcpn. Conditions
clear out with VFR late Thursday into Friday.
As of 945 PM Sunday...Steady 15 knot winds continue across the
waters this evening, and seas have continued to build. Latest
buoy reports show 3.6 foot seas now occurring at the Frying Pan
Shoals and CORMP Harbor buoy just south of Southport. I`ve
increased forecast sea heights to 3-4 feet overnight mainly
based on these current observations. An area of showers
developing 50-100 miles east of Charleston is moving northward
and should affect the Grand Strand and Cape Fear area coastal
waters mainly after midnight. Discussion from 730 PM follows...
Latest nearshore and buoy observations show south to southeast
winds 12-16 knots across the coastal waters with gusts exceeding
20 kt at the CORMP nearshore Sunset Beach buoy. I`ve
accordingly bumped up forecast wind speeds by around 5 knots
through the evening hours. These winds appear to be gradient
winds unaffected by convective outflow or any significant
seabreeze circulation given the fairly even temperatures from
land to sea currently.
Seas at area buoys are around 3 feet with dominant period around
5 seconds. These wave heights are slightly higher than forecast
nearshore, and since dominant periods are short it`s likely just
due to winds. Currently there are no showers occurring across
the coastal waters, however most models suggest scattered
showers and a few t-storms will develop after midnight.
Discussion from 300 PM follows...
Main concern over the waters will be developing thunderstorms
that could bring lightning, gusty shifting winds, and locally
high seas. Otherwise, fair prevalent conditions outside of
offshore storms are expected through Sunday as stationary front
remains draped across the region. Expect wave heights between 2
and 3 feet through Monday with main direction from the south
between 4 and 6 seconds and a swell from the southeast between 8
and 10 seconds.
A front will reach down and stall either near or just south of
local waters Tues into Tues night. This will shift winds around
to the N-NE on Tues, reaching up to 10 to 20 kts lat Tues into
Tues night. This will drive seas up to 3 to 5 ft.
Weak wave of low pressure will develop along this lingering
front and move up along the Southeast coast lifting off to the
northeast by Thurs. This will bring winds around to the S on Wed
and SW by Thurs as another cold front makes its way into the
Carolinas. Gradient later Wed through Thu will tighten up as
this cold front approaches. Seas dropping slightly on Wed will
be back up to 3 to 5 ft on Thurs in S-SW push. High pressure
will build down behind this cold front on Fri with winds
lightening up as they veer around to N and then NE to E by Fri
night as high pressure moves by to the north. Seas will drop
down below 3 ft late Fri into Sat.
SC...Beach Hazards Statement from 6 AM EDT Monday through Monday
evening for SCZ054.
Area Forecast Discussion...Updated Aviation
National Weather Service Saint Louis MO
638 PM CDT Sun Jun 9 2019
.SHORT TERM... (Through Late Monday Afternoon)
Issued at 333 PM CDT Sun Jun 9 2019
A cold front currently over northwest missouri will move southeast
tonight through Missouri and Illinois. Isolated showers will
continue to be possible along and ahead of the front this evening
over much of the area and for a few hours after midnight in east
central/southeast Missouri and southwest/south central Illinois. The
RAP does have a fair amount of instability (1500+ J/Kg MUCAPE) so a
few thunderstorms can`t be ruled out either. Once the front moves
through, rain chances should come to an end, and Monday continues
to look relatively cool and dry with lows tonight in the mid 50s
to low 60s and highs Monday in the mid 70s.
.LONG TERM... (Monday Night through Next Sunday)
Issued at 333 PM CDT Sun Jun 9 2019
Quiet weather continues on Tuesday under the influence of a large
surface ridge which extends from central Texas northeast into the
Great Lakes region. The ridge will move eastward Tuesday night and
Wednesday as a strong short wave aloft dips into the Mississippi
Valley. GFS and ECMF are in decent agreement with this wave and its
surface reflection as it moves across the Midwest into the Great
Lakes and Ohio Valley Wednesday and Wednesday night. 850mb moisture
convergence increases late Tuesday night ahead of the wave over
northwest Missouri as the low level jet strengthens, and this area
of moisture convergence translates east through Wednesday, and the
models correspondingly kick out a few tenths of an inch of QPF.
Therefore it looks like scattered showers and thunderstorms are
likely ahead of the surface front on Wednesday with the greatest
coverage closest to the best dynamic lift across northeast Missouri
and west central Illinois.
Current indications are that Thursday will be a dry day as the high
pressure behind Wednesday`s system moves across the Mississippi
Valley. However, northwest flow aloft in the wake of the shortwave
will escort cooler air aloft into the area which will steepen mid
level lapse rates...perhaps enough for afternoon showers to
develop over central Missouri which will be furthest away from the
center of the high at that time. Medium range guidance shows
another wave diving into the northern Plains on Friday, and
another reinforcing wave on Saturday. These waves push another
cold front into the mid Mississippi Valley with corresponding
chances for precipitation. There are timing and position
differences between the GFS and ECMWF with respect to this cold
front...but generally speaking late Friday night through Saturday
night have the most potential for precipitation as the front moves
slowly south through the area. There may be some lingering precip
on Sunday as well, but current indications are that the front
will have pushed south into the lower Mississippi Valley.
Temperatures through the period look near normal to a few degrees
below normal in the mid 70s to low 80s.
.AVIATION... (For the 00z TAFs through 00z Monday Evening)
Issued at 612 PM CDT Sun Jun 9 2019
A cold front is entering the area and will push through the
terminals this evening. An area of low VFR cigs upstream is
expected to filter into the area behind the front. Have raised
cigs at KCOU/KUIN as guidance has backed off suggesting MVFR cigs
this evening. Otherwise, clouds should mostly clear out of the
region by Mon morning. Winds will increase behind the front and
remain strong with gusts around 20 kts thru Mon afternoon.
SPECIFICS FOR KSTL/KSUS/KCPS: Guidance has backed off of MVFR cigs
behind the front. However, with the low VFR cigs currently
upstream of the area, will raise cigs into high MVFR and monitor
trends through the evening. Believe that cigs may lower somewhat
as cooling occurs. Otherwise, NW winds behind the front with
gusts around 20 kts.
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 61 77 56 79 / 20 0 0 0
Quincy 58 76 55 78 / 20 0 0 0
Columbia 57 76 53 79 / 20 0 0 0
Jefferson City 59 78 53 80 / 20 0 0 0
Salem 62 76 54 79 / 20 10 0 0
Farmington 60 76 52 79 / 20 5 0 0
Area Forecast Discussion
National Weather Service Marquette MI
738 PM EDT Sun Jun 9 2019
.SHORT TERM...(This evening through Monday)
Issued at 423 PM EDT SUN JUN 9 2019
WV imagery and RAP analysis indicated a mid/upper level trough from
north central Canada into the Plains resulting in sw flow through
the upper Mississippi Valley into the northern Great Lakes. At the
surface, southerly flow prevailed through Upper Michigan ahead of a
cold front from nw Ontario into wrn WI. Weak to moderate 305k-315k
isentropic lift ahead of a shrtwv that lifted north from the OH
valley supported sct rain showers over central and easter Upper
Michigan. Another band of showers extended from ne MN into wrn WI
associated with 800-600 mb fgen behind the cold front. Even with
MUCAPE values to around 500 J/Kg near KIWD, per RAP analysis over nw
WI to near KIWD, so far no tsra were noted.
Tonight, with continued moisture transport into eastern Upper
Michigan boosting PWAT values above 1.75 inch and increasing 250-300
mb div, expect that the rain over the east will continue to expand
and become heavier. Rain will also spread through western and
central Upper Michigan as the fgen behind the front advances through
the area. Some isold tsra may still be possible over the west early
where clearing had boosted instability.
Monday, the remaining fgen supported pcpn band will move continue to
move through the eastern cwa during the morning. Otherwise, expect
clearing from the west through the day with highs into the mid to
upper 60s. Northwest winds will become gusty to 20-30 mph as mixing
depths increse to around 6k ft. Dewpoints dropping into the mid 30s
will also drop RH values to around 30 pct inland.
.LONG TERM...(Monday night through Sunday)
Issued at 250 PM EDT SUN JUN 9 2019
The long-term period begins with the predominant mid-level short
wave exiting the region to the east. Whereas previously it had
looked like we would clear out quickly Monday evening, models now
linger enough moisture back behind the main wave along with several
much more subtle perturbations in the flow that it looks like Monday
evening will stay partly to mostly cloudy, though we do still
eventually clear by late Monday night/early Tuesday morning. With
that clearing, and with winds quickly diminishing after sunset,
Tuesday morning looks to be seasonably chilly with morning lows in
the 40s and perhaps even upper 30s in the normal cool spots. It does
not look like it will be cold enough for frost, however.
As high pressure passes by to the south, it still looks most of
Tuesday will be sunny except for some afternoon fair weather
cumulus. Still looking at fairly deep mixing up to about 750 mb and
therefore a warm and dry day Tuesday, with highs in the mid 70s.
Some guidance is more aggressive than others in bringing rain in
Tuesday afternoon already but given how dry the low levels look
Tuesday, decided to carve POPs back a bit from the preferred model
blend. This resulted in chance POPs for the far west and south-
central, and only slight chance for the central and Keweenaw. For
what it`s worth, the deterministic EC, which was one of the more
aggressive models with rain chances Tuesday afternoon, came back in
line/went drier with its 12z run.
Though Tuesday looks dry, the same can`t be said for Tuesday night
and Wednesday. As a deep short wave dives southeastward across the
Northern Plains and then rounds the corner south of Lake Michigan,
we`ll be dealing with a winter-like system Wednesday. It`ll feature
a cohesive wave of stratiform precip transitioning to a narrower
band as the mid-level fgen ramps up midday Wednesday. The amount of
rain any given area will see will depend on the exact track and
speed of the cyclone, which models still diverge on a bit. There`s
still a pretty big gap between the GFS`s 995 mb low over the
Mackinac Straits and the EC`s 1002 mb low near Toronto with each
model`s 12z run. Regardless of the exact track, the central and
eastern U.P. seem likely to get a soaking rain; it is how far west
that rain sets up on Wednesday that remains a question. Wednesday
also looks unpleasantly chilly given the rain and onshore flow, with
MOS guidance capping highs in the mid 50s for most and raw guidance
even cooler than that.
Showers linger Thursday and Friday as a second upper-level low is
progged to pivot around the main vort lobe down across the Great
Lakes Thursday into Friday. Unlike Wednesday, this won`t be a
continuous soaking rain, but rather a couple of cool, cloudy days
with frequent showers. Models begin to diverge by next weekend but
still have a consensus for continued unsettled weather.
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 731 PM EDT SUN JUN 9 2019
Light showers this evening along and ahead of the passage of a
cold front will lead to cigs at all terminals falling to MVFR
this evening and perhaps to IFR at times during the night. Winds
will also become gusty to around 20-25kt out of the nw after the
front passes. Look for improvement to VFR late Monday morning as
drier air works in behind the front.
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 423 PM EDT SUN JUN 9 2019
A cold front will cross Lake Superior tonight. In the wake of the
front, nw winds to 15-25kt will occur for a time over western Lake
Superior late aftn into tonight. Winds will be stronger over eastern
Lake Superior with 20-30kt expected late tonight and Mon. Winds will
diminsh to under 20kt Mon night/Tue. A low pres trof will then drop
se across the Upper Lakes early Wed. Depending on the strength of
the trof, another period of stronger nw winds to at least 15-25kt
will be possible after it passes, especially over eastern Lake