Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/13/18
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
525 PM MDT Tue Jun 12 2018
.AVIATION...
00Z TAF CYCLE
Upper high center to meander around central and eastern NM next 24
hours as moisture slowly increases into the circulation. A few
strong to severe thunderstorms until around 03Z over ne NM with wind
gusts to 50 kt and large hail as they move to the northeast and east.
These storms may produce an outflow boundary that pushes westward to
the east slopes of the Sangre de Cristo and Sandia/Manzano mts and
into the RGV, with the east wind impacting KSKX, KSAF and KABQ aft
03Z. Elsewhere over the higher terrain, isold to sct virga showers
until around 03Z. Smoke may drift into nw NM aft 03Z, with some vsby
restrictions until around 13/16Z. Expect isold to sct showers and
tstms to redevelop over the higher terrain aft 13/18Z.
&&
.PREV DISCUSSION...251 PM MDT Tue Jun 12 2018...
.SYNOPSIS...
Very hot temperatures will trend slightly cooler each day through
Friday before a significant surge of moisture moves into New Mexico
from the remnants of Hurricane Bud. A slight uptick in showers and
storms will occur each afternoon before the highest chances move
through Saturday. Temperatures will cool below normal with this
moisture surge over the weekend. The focus for showers and storms
will shift into eastern New Mexico Sunday and Monday while central
and western New Mexico heats back up. Another large scale moisture
surge is possible Tuesday and Wednesday as a strong back door cold
front slides southwest through New Mexico.
&&
.DISCUSSION...
This latest forecast package will remain cautiously optimistic with
regard to the extent of precipitation across the region through the
weekend.
Surface dewpoints currently range from the teens across eastern AZ
and western NM to the 30s across the eastern plains. 700mb dewpoint
depressions on the 12Z RAOB at KABQ were close to 50F. Expect one
more night of comfortably cool low temps over central and western NM
with strong radiational cooling and low humidity. The 12Z HRRR smoke
run shows another impulse of smoke draining into the Four Corners
region from the 416 Fire and valleys around the Gila region from the
Buzzard and Willow fires.
Convective coverage is shown to increase Wednesday by all model
guidance including the 12Z HREF. Enough dry air will still be in
place beneath the 592dm H5 high center to favor dry storms along and
west of the central mt chain with a mixture of wet and dry across
the eastern plains. The 12Z GFS shows a large mass of high clouds
spreading north late Wednesday from convection that develops over
the Sierra Madre ahead of Bud. This will be the first indication of
deeper moisture that begins increasing Thursday and Friday.
12Z models and ensembles are in decent agreement Thursday and Friday
that the upper high center will stretch into a ridge axis while
drifting eastward into the Arklatex region. The 12Z NAEFS indicates
the deeper atmospheric moisture advection will flow northward into
Arizona Thursday and remain west of the Cont Dvd Friday. Models
still note a westward extension of the ridge axis into NM both days
so the coverage of showers and storms still appears to be lackluster
for now.
All eyes are on Saturday as the main trough axis associated with the
remnants of Bud shifts eastward across NM. The GFS remains the most
bullish with moderate to heavy QPF Saturday and Saturday night while
the ECMWF and Canadian show precip coverage and intensity weakening
as it crosses NM later on Saturday. Thus, while PoP values increased
on model trends the forecast still remains on the conservative side.
Guyer
&&
.FIRE WEATHER...
The center of anticyclonic circulation aloft will begin to shift
east of NM through mid week as an upper level trough deepens on the
west coast. This will allow better moisture to flow northward into
the state with min humidities climbing a few to 13 percent Wednesday
afternoon. Scattered to isolated showers and thunderstorms will
result along the central mountain chain and across the NE plains,
with more isolated activity in the west and northwest mountains.
Cells out west will tend to be dry and gusty, except for a mixture
of wet and dry cells in the mountains of Socorro County. Storms will
mostly move toward the north and northeast at 10 to 20 mph. Dry or
hybrid wet/dry microbursts may result in erratic wind gusts up to 50
mph near storms and virga showers. The improving moisture will cause
high temperatures to fall a few to 7 degrees on Tuesday from today`s
readings.
Thursday through the end of the week the upper high will migrate
over the Mississippi River Valley and broaden, while a low pressure
system digs over the Great Basin. This will draw a surge of monsoon
moisture north and northeastward across the forecast area with
increasing shower and thunderstorm chances each day. Precipitable
water (PWAT) values are forecast to rise above normal starting
Thursday, then reach record values around 1-1.25 inches (by the GFS)
on Saturday as the remnants of Hurricane Bud cross. Models vary on
precipitation amounts, but it looks like the mountains and
continental divide region may receive around 0.75 to 1 inch of rain
during the latter half of the week. Many lower elevation locations
should receive at least a quarter inch of rain, except for locations
along NM`s eastern border where amounts will be less. The potential
exists for flash flooding below burn scars, especially Saturday.
In the wake of Bud`s remnants, drier air will filter over the state
from the west with a significant downtick in convection Sunday and
again Monday. Recycled moisture should allow mainly isolated showers
and thunderstorms to redevelop in the west Sunday, while better
moisture lingers in the east with scattered to isolated activity.
The northern mountains and far easter plains will be favored for
scattered to isolated storms on Monday, as a back door cold front
enters the northeast with another shot of moisture. The back door
cold front may push into western areas on Tuesday increasing
precipitation chances there as well.
High temperatures will drop to near and below normal as this early
season burst of moisture arrives.
44
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Wakefield VA
949 PM EDT Tue Jun 12 2018
.SYNOPSIS...
A warm front slowly returns back north late tonight through
Wednesday morning then dissipates. A cold front crosses the area
Wednesday night into Thursday to be followed by high pressure
building over the region late Thursday through the weekend.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
As of 950 PM EDT Tuesday...
High pressure remains over the VA piedmont, with a trough off
the NC coast. Scattered showers continue to stream nwd over
coastal NE NC, SE VA, and the VA Ern Shore associated with this
trough. Cloudy this evening with temperatures generally in the
mid 60s to around 70F. Scattered showers are expected to
continue from the VA Ern Shore through SE VA and coastal NE NC
through midnight. The latest HRRR trends support a chc of
showers shifting to the Nrn Neck and Middle Peninsula through
the early overnight hours, then toward the MD Ern Shore late
tonight through early Wednesday morning. A warm front slowly
lifts back N late tonight resulting in stratus and some fog.
Expecting mainly stratus, with the best potential for fog over
s-central VA and interior NE NC. Lows tonight will mainly be in
the low 60s NW to 65-70F elsewhere.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
As of 315 PM EDT Tuesday...
Frontal boundary dissipates over the local area by Wed
morning...as weak upper troughing west of the region allows
for increasing WSW flow aloft. A stronger upper trough over the
northern Great Lakes will shift ESE through the day into the St
Lawrence Valley. The low level pressure gradient will tighten
in between sfc hi pres well off the coast and lo pres N of the
Great Lakes. This will result in most if not all of the local
area breaking into the warm sector by late Wed morning or Wed
afternoon. SW winds will avg 10-15 mph and should see skies avg
out partly sunny after early morning low clouds. A very low prob
for late day tstms Wed (only about 20% w/ minimal lift over the
region despite a return to very warm and fairly humid
conditions). Highs Wed will avg in the l-m80s on the ern shore
to the u80s to around 90F elsewhere.
Flow aloft becomes more WNW Wed night into Thu w/ a (weak) frontal
boundary approaching the local area from the NW. ISOLD-SCT
tstms (mainly) Wed eve...partly cloudy Wed night w/ lows in the
u60s-l70s. Enough of a NNW push aloft to bring some drier air
into nrn/central areas of the FA Thu, while remaining a little
more humid over far srn/SE VA and NE NC. Partly sunny S Thu
and mostly sunny N with 20-30% PoPs for afternoon SHRAS and
tstms mainly along-S of the VA-NC boarder. PoPs 10% or less
N and central zones. Highs in the mid to upper 80s.
Models continuing to show a sharpening/building of an upper
ridge from the srn Plains to the Great Lakes beginning Fri while
trough aloft amplifies off the E coast. The result will be hi
pres building into the local area from the NNW...pushing
unsettled/convective wx mainly S and SW of the FA. Lows Thu
night from the u50s to l60s...except m60s at the coast in SE
VA/NE NC. Mostly sunny Fri w/ the humidity remains low (dew
points mainly the u50s-l60s) and highs ranging through the 80s.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 400 PM EDT Tuesday...
Guidance continues to show an upper-level ridge building from the
Plains to the southern Great Lakes this weekend through early
next week. The result will hot, humid, but mainly dry weather
for much of the extended period. Monday has the potential to be
the hottest day of the year so far in spots as both the latest
12z GFS and ECMWF are forecasting 850 hPa temperatures of
20-22C in central/southern VA. There is a slight chance of a few
isolated afternoon/evening t-storms (mainly over the western
half of the CWA) on Sunday/Monday. Both the GFS and ECMWF have a
cold front approaching the region from the north next Tuesday-
Wednesday. This cold front will bring a better chance of more
widespread showers/t-storms. Currently have PoPs no higher than
40% since we are still one week out.
Highs in the mid to upper 80s on Saturday warming to near 90 on
Sunday. Hot and humid weather expected on both Monday and Tuesday
with forecast highs between 90 and 95 degrees. Expect morning lows
between 67-74 from Saturday through next Tuesday.
&&
.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
As of 820 PM EDT Tuesday...
BKN-OVC MVFR/IFR cigs are occurring at RIC/PHF/ORF/ECG as of
00z, with BKN-OVC VFR cigs ~5kft at SBY. Sct showers continue
to lift nwd over SE VA/NE NC and any showers have the potential
to reduce vsby to 2-5sm. Cigs are expected to gradually fall
overnight with all sites forecast to become IFR. Additionally
some 2-5sm BR is possible late tonight into early Wednesday
morning. A light ESE wind will become SSW by morning as a warm
front lifts through the area. Cigs are expected to lift and
scatter later Wednesday morning in deep layer SW flow ahead of
an approaching cold front. A SW wind is expected to average
8-12kt by aftn.
An isolated shower or tstm is possible Wednesday evening. The
cold front is expected to drop through central and ern VA early
Thursday morning, and then into ern NC by early Thursday aftn. A
few showers/tstms could develop along the boundary over SE VA/NE
NC midday Thursday into mid-aftn. A drier airmass and high
pressure build into the region Thursday night through Saturday.
High pressure moves offshore by Sunday.
&&
.MARINE...
As of 400 PM EDT Tuesday...
A small craft advisory remains in effect for the northern
coastal waters and entrance to the Ches Bay until 7 pm, and
continue through tonight for the southern coastal waters mainly
due to the short period waves of 5 to 6 ft. Onshore winds will
gradually turn southeasterly tonight and diminish as the high
off the New England moves offshore. Winds will then turn S-SW on
Wednesday as the surface front over the Carolinas moves north
of the waters. Another cold front passes through the waters
Thursday morning, turning the winds N-NW, but winds do not look
strong enough for Small craft conditions. Sub-SCA conditions
expected through the end of the week and into the weekend as
high pressure builds over the middle Atlantic.
&&
.TIDES/COASTAL FLOODING...
As of 400 PM EDT Tuesday...
High rip current risk over southern waters late this afternoon
into this evening with 4-6 ft nearshore waves, and a moderate
rip risk over northern waters.
Tidal departures across much of the area still around 1 ft
above astronomical tide. With the already high astronomical
tide in place, some places will see minor coastal flooding again
this evening, and most likely again tomorrow evening despite
the onshore wind diminishing.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...Coastal Flood Advisory until 6 AM EDT Wednesday for MDZ021>023.
NC...None.
VA...Coastal Flood Advisory until 2 AM EDT Wednesday for VAZ099-100.
Coastal Flood Advisory until 5 AM EDT Wednesday for VAZ075-077.
Coastal Flood Advisory until 1 AM EDT Wednesday for VAZ084-086.
MARINE...Small Craft Advisory until 10 PM EDT this evening for ANZ634-
650-652.
Small Craft Advisory until 4 AM EDT Wednesday for ANZ654-656-
658.
&&
$$
SYNOPSIS...ALB/LKB
NEAR TERM...AJZ/ALB
SHORT TERM...ALB/LKB
LONG TERM...ERI
AVIATION...AJZ
MARINE...MRD
TIDES/COASTAL FLOODING...AKQ
Area Forecast Discussion
National Weather Service La Crosse WI
658 PM CDT Tue Jun 12 2018
.UPDATE...
Issued at 658 PM CDT Tue Jun 12 2018
Have made some slight migrations to the forecast to concentrate
the severe/strong storm risk from one SLGT area into two smaller areas
where the ingredients seem to suggest a bit higher storm coverage
Area 1: The southern area south of about Highway 18 in NE IA and
SW WI where the MLCAPE pool is around 1500 J/Kg with overlaid
deeper wind shear for supercells.
Area 2: The lower /relatively/ instability area further north but
ahead of the deep and strong shortwave trough heading in with
deep shear for supercells...near and north of I-94 in WI. Have
also slowed the timing this evening to mainly be a 9pm to 12 am
window.
Overall the SPC Deep moisture convergence is highest where the
storm initiation has recently occurred near the Twin Cities and
northwest of Fort Dodge in IA. This is handled well in the recent
RAP forecasts of 925mb thetaE convergence and the RAP tracks
these two areas east over the next hours to bring the storms to
the forecast area. HRRR runs have been targeting these two areas
since I walked in at 4 pm. The area in IA may shift southeast and
just brush the far southern areas south of highway 18....and may
miss the WFO La Crosse northeast Iowa counties totally.
Have refined hourly storm chances in the forecast as well to
represent this thinking.
With deep shear, severe storm chances have to be considered. CAPE
will diminish slowly through the evening thus best chances for
severe storms do as well. However, dynamical forcing of strong
shortwave trough in northern area of storms will make up for some
of the CAPE loss.
&&
.SHORT TERM...(This evening through Wednesday)
Issued at 305 PM CDT Tue Jun 12 2018
Plenty of cloud cover has remained over the area today within a
fairly moist air mass ahead of a surface boundary slowly approaching
from the west across Minnesota. A few showers/sprinkles have
developed at times today with weak isentropic upglide. Of interest
will be a vigorous shortwave aloft that will approach northern
Wisconsin this evening. Stronger flow will support deep layer
shear of 40-50 kts. Limiting factors include timing of the wave
and instability with RAP MUCAPE ranging from 500-1000 J/kg across
northern Wisconsin to near 2000 J/kg in northeast Iowa. Will have
to watch cloud trends late this afternoon for any clearing. With
the greatest lift with the shortwave across northern Wisconsin,
expect the highest chances for storms in this area, with
isolated/scattered storms possible farther south along the surface
boundary where instability is higher but forcing from the upper
wave is weaker. Given the forcing and shear present, could see a
few strong to severe storms with a hail/wind threat, mainly this
evening, before large scale subsidence takes hold as the shortwave
passes to the east overnight.
Wednesday will be a very nice day as precipitable water values fall
to around half an inch with dry high pressure over the area. Highs
will be around 80 in many areas with mostly sunny skies.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 305 PM CDT Tue Jun 12 2018
The main concerns through the extended period will be a return to
hot temps and thunderstorm chances.
Even by Thursday mid/upper ridging will be beginning to build across
the Midwest with temps/moisture beginning to increase. The ridge
centered over the Mid Mississippi Valley will remain in place
through the weekend downstream from a deepening upper trough over
the western US. An upper trough passing to the north and east
will help to knock the ridge down early next week and drive a
front through the area.
Plenty of Gulf moisture will be advected northward on the western
periphery of the ridge setting up a humid/unstable pattern across
the region into the Midwest through the weekend with the GFS
indicating precipitable water values could exceed 1.75 inches at
times. Showers/storms are possible by Thur night and Friday with
increasing moisture transport/warm advection. A frontal boundary
will likely be situated somewhere from the northern plains through
the upper Great Lakes with occasional thunderstorm complexes
riding the periphery of the ridge near the frontal zone through
the weekend. Will have to watch where this boundary sets up and
how far south into the more capped warm sector any of these storms
can reach. Could see heavier rainfall as well as some stronger
storms, though, near the frontal zone,currently favoring northern
parts of Minnesota and Wisconsin.
South of the front, heat will be the main concern. The 12.12Z
ECMWF shows 925 mb temps of 27-30C over much of the area Fri-Sun
afternoons with the GFS a few degrees cooler. In the absence of
any storms that sneak south or thicker cloud cover, the higher
ECMWF 925 mb temps would support highs well into the 90s. Dew
points in the 60s to near 70F would result in even higher heat
indices, leading to potential heat concerns. Overnight lows likely
will remain near or above 70 over the weekend for much of the
area. Some uncertainty remains given potential for convection and
questions exactly where the boundary will be set up, but it
certainly looks like a very warm/hot and humid weekend. Temps may
trend downward behind a front early next week, but timing of the
front is still in question.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 658 PM CDT Tue Jun 12 2018
Have removed the VCTS from the TAF sites as confidence in storms
being around is falling.
Overall there is some instability around the area ahead of a
strong weather system heading into Minnesota. This will provide
storm initiation near the Twin Cities this evening and these
storms will shift east. It seems the activity may build south, but
not far enough to reach the TAF sites.
Plan on monitoring this closely and should conditions warrant,
will need to add CB and VCTS into the TAFs again. Current thinking
is a VFR CIG with storms passing well north of the airfields in
the 02-05Z window making them circum-navigatable.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
UPDATE...Baumgardt
SHORT TERM...JM
LONG TERM...JM
AVIATION...Baumgardt
Area Forecast Discussion
National Weather Service Charleston SC
1045 PM EDT Tue Jun 12 2018
.SYNOPSIS...
A stationary front will meander across the area today, then
lift north as a warm front by Wednesday. A trough is forecasted
to prevail inland Wednesday and Thursday followed by a slow
moving backdoor cold front Friday into this weekend.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 1041 PM: Convection over land should continue to weaken
over the next hour, then coverage should decrease to isolated.
Based on radar trends and latest HRRR, convection should remain
scattered over the near shore areas through late tonight. I will
adjust PoP timing and values.
As of 915 PM: Deep convection continues across portions of SE GA
and SC. However, most of the coastal counties have been worked
over and stability values continue to increase. A few inland GA
area remain unstable and could see showers and thunderstorms
develop as the outflow advances. I will keep CHC PoPs in the
forecast for the rest of this evening. Any storms that do
develop will move very slowly.
As of 750 PM: Convection is expected to gradually dissipate
through the rest of the evening, leaving a few showers/thunderstorms
over the marine areas. I will update the forecast to adjust
PoPs and weather. Temperatures within the rain-cooled areas will
range in the mid to upper 70s through mid evening, then should
begin to gradually cool. I will update the low temperature
forecast to range from the upper 60s inland SC to the low 70s
along the coast.
As of 610 PM: Convection over the SC Lowcountry has generally
dissipated. However, convection across SE GA is likely reach a
peak in coverage. I will update the forecast to adjust PoPs and
Weather. Latest tide forecasts adjusted for observed anomalies
show water levels just above advisory thresholds at both the
downtown Charleston and Fort Pulaski gauges.
Previous Discussion:
Tonight: Fairly widespread convection has developed along a
stalled front today. The primary focus has been in the
Charleston vicinity where storms initially lined up west-east
this morning. The storms have since become more north-south
oriented as typical diurnal clearing has developed across the
ocean behind a weak seabreeze circulation. Locally heavy
rainfall has occurred, and there was even video evidence that a
waterspout occurred off the coast of Isle of Palms late this
morning.
The second convective focus has been along the lower Savannah
River along the westward extension of the front. Activity has
generally been less significant here, however the collision of
the seabreeze with the front led to one particularly strong
storm between Savannah and Tybee Island earlier.
Convection should gradually diminish in coverage this evening,
perhaps shifting back out of the water as instability wanes
inland. The 12z NAM along with the more recent runs of the RAP
and HRRR seem to have a good handle on local winds and the
current frontal position, and show a shift in the location of
convection pretty clearly overnight. Some debris cloudiness
should linger overnight inland, perhaps enough to keep any late
night fog isolated in coverage.
With a humid, tropical airmass continuing lows should only fall
into the lower to middle 70s.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
The mid-levels will consist of a weak trough over the Southeast
Wednesday and Thursday. Friday the trough shifts offshore as a
strong ridge builds from the west. At the surface, a warm front will
be north of the area Wednesday. A trough will be inland Wednesday
and Thursday while high pressure remains in the Atlantic. A cold
front will approach from the north Friday. Plenty of moisture will
remain in place during the short term with PWATs ~2". The
instability remains in place each afternoon with Wednesday and
Thursday being comparable. Friday the models seem to indicate less
instability despite the approaching front. Wednesday we trended POPs
up, but kept them at chance Thursday and Friday. POPs will be the
highest during the afternoon and along the sea breeze. We may need
to increase POPs on Friday due to the approaching front.
Showers/thunderstorms should remain concentrated over the coastal
waters during the overnight/morning hours, migrating/developing
inland during the afternoon/evening hours with the sea breeze and
outflow boundaries. Locally greater coverage of
showers/thunderstorms should be expected. The main threat will be
heavy rainfall and locally gusty winds. Daytime temperatures will be
near normal and nighttime temperatures may be a few degrees above
normal.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A cold front will be just north or over the area Saturday. The front
will slowly move south during the long term, possibly becoming
located south of our forecast area by early next week. The weather
will be highly dependent on the location of the front. The forecast
is for summertime convection on Saturday. The convective potential
should be much lower early next week as the front moves south. North
of the front will be slightly drier conditions and maybe cooler
temperatures.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
Convection is expected to gradually dissipate through the rest
of the evening, leaving a few showers/thunderstorms over the
marine areas. The forecast challenge will be the timing and
placement of restrictive ceilings tonight. Based on forecast
soundings and MOS, I will indicate MVFR ceilings at KCHS through
tonight, with a period of IFR ceilings around dawn. KSAV should
see MVFR ceilings develop by 8Z and remain until mid morning
Wed. Deep convection should develop along a seabreeze at both
terminals during the afternoon and evening, highlighted with a
PROB30.
Extended Aviation Outlook: Mainly VFR. Brief flight restrictions are
possible in showers and/or thunderstorms, mainly each afternoon and
early evening.
&&
.MARINE...
Tonight: A backdoor cold front drifted down to between
Charleston and Hilton Head earlier this morning. A weak
seabreeze has since made the front harder to locate but it
likely still sits south of Charleston based on northerly wind
direction still observed in Charleston and points north. Light
winds on either side of the front should continue overnight,
strengthening only to 10 knots from the SW along the GA
nearshore and offshore waters late tonight. Based on buoy
reports seas are likely still 2-3 feet, with no significant
change anticipated through daybreak Wednesday. Showers and
thunderstorms have mainly shifted inland, but may redevelop back
off the coast overnight, with 30-50 percent coverage expected.
Extended Marine: A warm front will be lifting north of the area
Wednesday. Wednesday and Thursday the coastal waters will be
sandwiched between a trough inland and Atlantic high pressure. A
southward moving cold front will slowly move through the area Friday
into the weekend. Expect mostly southwest winds across the waters
through Friday. The exception will be during the afternoon near the
coast where winds will likely become more south and increase a bit
in speed in association with the sea breeze. Winds will transition
this weekend with the front. Occasional thunderstorms could bring
gusty/erratic winds and frequent lightning, especially during the
overnight hours for the entire forecast period.
&&
.TIDES/COASTAL FLOODING...
High tides associated with this month`s New Moon should allow
the evening high tides Wednesday through Friday to approach
coastal flood advisory levels.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
NEAR TERM...NED
SHORT TERM...
LONG TERM...
AVIATION...NED
MARINE...
TIDES/COASTAL FLOODING...
Area Forecast Discussion
National Weather Service Duluth MN
643 PM CDT Tue Jun 12 2018
.SHORT TERM...(This evening through Wednesday)
Issued at 332 PM CDT Tue Jun 12 2018
A slow moving cold front extending from Ontario, through the MN
Arrowhead, and through northwest WI is poised to accelerate and
finally move out of the Northland by later this evening. An
approaching, potent shortwave trough from the west will give it
the acceleration to pick up steam. Extensive cloud cover today
is hanging on much longer than forecast, which is limiting the
daytime heating, yet late afternoon and evening clearing may
provide more heating to build up instability for thunderstorms.
This approaching wave will bring moderate to strong forcing for
ascent by this evening when it gets closer to the region, and the
cold front will also provide some forcing. There is a good chance
thunderstorms will develop by this evening in northwest WI and the
MN Arrowhead, and some of the storms in WI this evening could be
strong to severe. There will be 1000 to 2000 J/kg of MUCAPE and 40
to 50 knots of deep layer wind shear in northwest WI, enough to
result in organized storms capable of hail and strong wind gusts.
The precipitable water values will be about 1.25 inches, an
environment that may lead to brief heavy rain. The limiting
factors on severe weather will be that the deep layer wind shear
is mainly the result of wind shear, and not direction shear, and
there will be a lack of low-level wind flow to feed the storms.
Have been leaning on the HRRR and RAP for timing and precipitation
chances, which seem to have been doing well with the showers and
weak storms we have seen today. Plus, these models have been
better with the cloud cover trends, which will obviously play a
big role in the destabilization of the boundary layer.
There will be clearing overnight in the wake of the passing cold
front and shortwave trough. High pressure will move into the
region going into Wednesday. Overnight lows will be in the upper
40s and low 50s. Wednesday looks sunny and breezy with highs in
the middle to upper 70s.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 332 PM CDT Tue Jun 12 2018
Several rounds of thunderstorms, heavy rainfall, and possible
flooding Friday through late Sunday night remain the primary
concerns during the long term.
Ridging at the surface and aloft to continue Wednesday night and
Thursday over the Northland. Storms over the Dakotas Wednesday
evening should slide to our south on the periphery of the surface
ridge. Highs Thursday will reach the upper 60s to low 80s.
A more active pattern is expected Thursday night through the
weekend. A blocking pattern is forecast to set up over the
Northern Pacific with the eastern anchor over the Intermountain
West. The mid-level ridge will slide to the Deep South setting up
ample moisture flow from both the Gulf and the Pacific into the
Upper Midwest. The upper level features will slowly evolve from
Thursday night through early next week as shortwave pass around
the base of the low over the western states and north of the ridge
over the south.
A warm front will lift into the Northland Thursday afternoon and
evening. Thunderstorm chances increase Thursday evening, and
especially overnight, in response to surface convergence and a
strengthening low-level jet. The complex of thunderstorms will
migrate generally eastward Friday morning as it weakens. A cool
front will move eastward across Minnesota and northwest Ontario on
Friday, which will set the stage for another round of storms
Friday afternoon and evening. Some of the storms may be strong to
severe with 1 km mixed layer CAPE of 2 to 4 kJ/kg forecast. Deep
layer shear will be lacking early in the evening, so initial
storms may pulse up and down creating a damaging wind threat and a
potential for large hail. The storm threat continues during the
night as precipitable water values increase on a strengthening
low-level jet. PWATs from the GFS of 1.7 to 2 inches are forecast
overnight with robust 850 mb moisture transport focused south of
US 2 in Minnesota and Wisconsin. In addition to the abundant
moisture available, storm motions will be oblique to the LLJ
suggesting training storms are possible. Storms moving over the
same locations overnight will result in excessive rainfall and a
potential for flash flooding late Friday night and Saturday
morning.
The baroclinic zone will become quasi-stationary over Wisconsin
and Michigan, Saturday afternoon but is forecast to lift northward
as a warm front over Minnesota and the Dakotas. The Pacific
moisture stream will be enhanced by that time as the remnants of
Hurricane Bud stream northward across the Four Corners region and
into the Plains. Strong to severe storms are possible once again
by late afternoon with stronger deep-layer shear and MLCAPE of 2-4
kJ/kg once again. GFS PWATs climb to between 1.8 and 2.2 inches
from the Iron Range south by late afternoon. Training storms are
possible Saturday night and early Sunday morning raising the risk
of flash flooding once again.
The front will become quasi-stationary once again from southwest
Minnesota to northern Wisconsin and Upper Michigan. Strong
thunderstorms are possible once again south of the boundary from
central Minnesota across nearly all of northern Wisconsin.
Afternoon MLCAPE values will push into the 1.5 to 3 kJ/kg range
with deep layer shear of 35 to 40 knots. The severe storm threat
will transition once again to heavy rainfall during the evening
and overnight hours with flash flooding.
Showers and storms will continue Monday morning in northwest
Wisconsin and gradually taper off by afternoon. High pressure will
build into the Northland once again ushering in a quieter period
Monday night into Tuesday.
In addition to the severe weather and flooding potential this
weekend, temperatures will climb into the middle 80s for the
southern half of the forecast area. Heat index values could
approach 90 degrees south of US Highway 2 in Minnesota and
Wisconsin.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 629 PM CDT Tue Jun 12 2018
A cold front is expected to set off some spotty showers and
thunderstorms this evening, before moving off to the east. While
the majority of thunderstorm activity is expected to affect areas
of northwest Wisconsin, there could be a shower or thunderstorm
this evening from KBRD to KHIB to KDLH for a short time. VFR
conditions will be widespread, but the showers or storms could
briefly reduce conditions to MVFR. Conditions will then improve
behind the front, although there may be a bit of fog later in the
night. Wednesday is shaping up to be a VFR day with mostly clear
skies.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 52 78 53 77 / 10 0 0 0
INL 46 78 48 81 / 10 0 0 0
BRD 51 78 54 80 / 10 0 0 10
HYR 52 78 50 79 / 40 0 0 0
ASX 53 78 52 78 / 40 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&
$$
SHORT TERM...Grochocinski
LONG TERM...Huyck
AVIATION...DAP
Area Forecast Discussion
National Weather Service Des Moines IA
701 PM CDT Tue Jun 12 2018
.SHORT TERM.../Tonight through Wednesday/
Issued at 319 PM CDT Tue Jun 12 2018
Decent 500mb shortwave looks to cut across Minnesota dragging a
cold front through the state late tonight. The latest HRRR (and
preceding runs) remains consistent with bringing a few storms
into the northwest by around 00z today. Certainly plenty of MUCAPE
present this afternoon into this evening and enough forcing with
the fropa to be concerned with the severe storm potential this
evening over northern Iowa. Shear profiles and helicity are weak,
especially in the lower 3km, and thus have very low confidence
with the tornado threat. With LCL heights range around 750-1000m
and DCAPE around 1000 J/kg, more concerned with the elevated hail
threat and damaging winds.
Surface high pressure builds into the state throughout the day
Wednesday providing a very pleasant and cool day across the
forecast area.
.LONG TERM.../Wednesday night through Tuesday/
Issued at 319 PM CDT Tue Jun 12 2018
Wednesday night into Thursday...Strong mid-level theta-e
advection punches into the state late Wednesday night with the
LLJ just to the west of the forecast area during this time.
Greatest storm chances look to be past 06z Thursday through 18z
across western to northern Iowa. The time of day looks to limit
the severe threat with the lack of significant instability and
deep forcing available.
Friday through Tuesday...the main forecast concern was focused on
the heat wave beginning Friday and lasting into early next week.
Confident in three consecutive days of max temperatures well into
the 90s from Friday through Sunday. There were a couple minor
changes with the ongoing forecast, but significant enough that the
heat index forecast was shifted higher. Both Friday and Saturday
afternoons are likely to be slightly windier with models in good
agreement with the deeper mixing. Friday is expected to see the
stronger winds and with highs in the mid-90s and dew points in the
lower 70s, it`ll feel like a blast furnace Friday afternoon.
Saturday, and even Sunday, will not provide any relief. Winds
appear to be weaker and the dew points look to be slightly higher
with less mixing. Regardless, sultry heat index values in the
triple digits are expected during the peak heating all three days
Friday to Sunday. The biggest thing to monitor is the surface dew
points over the weekend as the current forecast still might be a
degree or two too low, especially if the mixing does not
materialize. Overnight lows remain in the 70s over the weekend,
providing little relief the heat and confidence is increasing a
headline might be needed by Friday through Sunday.
Monday into Tuesday...upper level ridge of high pressure begins to
break down with a cold front anticipated to push south across the
state Monday afternoon into the evening per GFS. The ECMWF remains
dry Monday as it suggests the front through the state by Tuesday.
Thus, there is the potential for Monday to be another hot day if the
ECMWF solution holds true.
&&
.AVIATION.../For the 00Z TAFS through 00Z Wednesday evening/
Issued at 700 PM CDT Tue Jun 12 2018
The primary concern will be thunder trends and restrictions
caused by those storms this evening with high confidence in VFR
conditions through the period otherwise. Have included VCTS
wording were thunder is possible over the next several hours,
mainly north, with VCSH or nil wording elsewhere until confidence
increases. Likely no non-VFR mention anywhere until confidence
increases.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...Podrazik
LONG TERM...Podrazik
AVIATION...Small
Area Forecast Discussion
National Weather Service Grand Rapids MI
1026 PM EDT Tue Jun 12 2018
LATEST UPDATE...
Update
.SYNOPSIS...
Issued at 327 PM EDT Tue Jun 12 2018
A few showers and perhaps a weak thunderstorms or two will
develop this afternoon as a warm and humid airmass moves into the
area. Locally heavy rainfall is possible under the most intense
cells. A cold front will then sweep through the Great Lakes
tonight and into Wednesday morning along which a few showers are
possible. Cooler and less humid air will then settle into the area
for the remainder of the week.
&&
.UPDATE...
Issued at 1025 PM EDT Tue Jun 12 2018
I have increased the pop to around 50 percent during the early
morning hours of Wednesday (mostly from 3 am till 8 am). Seems
there is a decent chance some of this will be isolated
thunderstorms.
Based on the latest data from the high resolution models and
looking also at SPC SREF 3 hour thunderstorm probability from the
21z run it seems there is a better spike in the unstable cape in
the 3 am till 9 am time frame as the cold front comes through.
Curiously the NAM12 thunderstorm probability rises to 90 percent
in that time frame. Also the HRRR and ESRL HRRR do show the
convection developing near MSP and north of DSM correctly and
both models develop a broken area of convection that moves
through this area from North to South (entire CWA alone the lake
shore) in the 4 am till 8 am time frame. The RAP model moisture
transport vectors in the 4 am till 8 am time frame have increased
significantly over the past few model runs with the strongest
values between HOL and MKG. Still the best dynamics are north of
our CWA. Even so the 850 to 700 rh, which is usually a good
indication where the rain will be rises to between 80 and 85% as
far south as HOL around sunrise.
As for the risk of thunderstorms, the cape is narrow but extends
to near 42,000 ft. The most unstable cape on RAP model reach 1,200
j/kg south of Grand Haven and west of US-131 in the 4 am through 8
am time frame.
So my spin the developing line of convection will increase over
the next few hours and most locations in SW Lower, west of US-131
will see some showers possibly an isolated thunderstorm in the 3
am to 8 am time frame.
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 327 PM EDT Tue Jun 12 2018
While dew points continue to slowly increase across our area,
abundant low-level cloud cover across the lower third of lower
Michigan as well as a lack of any synoptic or mesoscale feature to
aid in southerly moisture transport has really hampered
destabilization this afternoon. Unsurprisingly, short-term model
guidance continues to back off on precipitation potential this
evening which at this point seems quite reasonable. Where skies
have been somewhat clear today, meager instability is being
achieved (SPC RAP analyzed 500 J/kg or so of MUCAPE) with shallow
but somewhat congested cumulus streets developing along a line
from roughly Traverse City southward toward Muskegon. With these
considerations in mind, the expectation is (still) for a few
scattered showers to develop along the Michigan/Indiana border
(where somewhat better moisture resides) and along the far
northern CWA with dry conditions expected elsewhere. Given very
meager low- and mid-level lapse rates, I really don`t think we`ll
see widespread thunder. However, with PWATS > 1 inch, showers
that do develop are likely to produce moderate to heavy rainfall.
Attention then turns to the potential for some quick-moving
showers along a cold front expected to sweep through the area
tomorrow morning. While showers and storms are expected to
develop along the front in Wisconsin and the U.P. of Michigan this
evening, coverage will likely decrease overnight over Lake
Michigan except across the north in closer proximity to the
strongest forcing. A few showers may redevelop along the front by
mid-morning tomorrow though coverage is expected to be widely
scattered at best. More robust development is expected east of our
area in far eastern Michigan and into southern Ontario where
diurnal timing will be more favorable.
Of perhaps more concern is the potential for strong northwesterly
winds along the backside of the cold front. Model guidance has
really started to hone in on a the development of a narrow but
intense low-level core of winds along the backside of a deepening
low pressure system in eastern Ontario with 850 mb (925 mb) winds
approaching 70 kts (50 kts) over parts of the upper Great Lakes.
Based on the track of the low, the strongest winds are expected to
occur over the eastern U.P. of Michigan southeastward into
southern Quebec. Locally, winds may gust upwards of 30-35 mph
northeast of a line from Bristol to Lansing, with 20-30 mph
elsewhere across western lower Michigan.
Thursday looks quiet with dry and sunny conditions expected.
.LONG TERM...(Friday through Tuesday)
Issued at 327 PM EDT Tue Jun 12 2018
The main challenges in the long term deal with the potential for
storms and high heat over the weekend. There is some potential that
warmer temperatures aloft over the CWA may limit the convective
risk. For now will hold onto the potential for some storms.
The pattern will support the formation of some nocturnal MCS`s over
the weekend. A southerly low level jet will reach into the Upper
Plains Friday night. That should set off a cluster of storms. As
this system tracks through the mid level ridge in that region...is
should drop southeast with time..and into parts of the Western Great
Lakes region. Will feature rather high POPs for this possible
system...mainly northern zones.
Similar kind of setup for Saturday night...although the low level
jet will be a little further east and does veer somewhat with time.
Additional showers and storms look possible.
Then with Monday...the wind fields look stronger here in MI with
instability around. A cold front will be pressing down from the
north. Given the combination of these systems...it looks like
thunderstorms could become numerous....with a few stronger storms
possible. Heavy rain could also be a risk given the high PWAT values
forecasted.
It looks likely that some 90s will arrive over the weekend. Sunday
looks to be the warmest day. If the surface front comes through
later Monday...90s will be possible then as well. When you combine
surface dew points closer to 70 and the potential for ambient
temperatures to reach 90...apparent temperatures could make a run at
100 degrees.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 755 PM EDT Tue Jun 12 2018
We currently have MVFR cigs along I-94 TAF sites and VFR along
I-96 TAF sites. There are a few isolated shallow, but heavy rain
showers around the area but I do not expect them to impact any of
the TAF sites before they dissipate shortly after sunset.
The main issue for tonight through is the potential for dense fog
and LIFR cigs/vsby after midnight till around sunrise. There
currently is a large area of dense fog over Lake Michigan that can
be seen in the visible satellite images and slow on coastal web
cams (at 7 pm). As front cold front approaches the area this will
turn winds below 1000 ft to a more southwest to westerly
direction. That in turn will bring the low clouds and fog inland.
I do not expect the low visibilities to reach all TAF sites but
the low ceiling will. Once the front comes through (12-15z) skies
should clear from west to east. There may be a few showers with
the cold front but that should not change cigs or vis
significantly from what it already would be.
Once the front goes through skies should be and it will be breezy.
Expect NW winds of 15 to 25 mph at just about all of our TAF sites
during the day Tuesday.
&&
.MARINE...
Issued at 327 PM EDT Tue Jun 12 2018
Areas of dense fog may develop tonight over Lake Michigan as a
moist airmass continues to move over the relatively cold water.
The fog will quickly abate Wednesday morning as a cold front
sweeps through the lower Great Lakes bringing drier air and
increasing northwesterly winds to 15-20 kts. The highest winds
will be short lived with gusts decreasing to 5-10 kts by Wednesday
evening. Relatively calm conditions are then expected for the
remainder of the week.
&&
.HYDROLOGY...
Issued at 327 PM EDT Tue Jun 12 2018
Scattered showers and thunderstorms today through Wednesday morning
will have the potential to produce locally heavy rain. Rainfall
should be brief, but may cause ponding on roads and low-lying areas,
and rapids rises in small creeks and streams. No flooding of
mainstem rivers (such as the Grand, Kalamazoo, Muskegon) is
expected. Dry weather is expected Wednesday afternoon through
Friday. A more active pattern then looks to set up over the Great
Lakes region Saturday through Monday. This could lead to multiple
rounds of heavy rain affecting the same location, and will need to
be monitored.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...Dense Fog Advisory until 8 AM EDT Wednesday for LMZ844>849.
Small Craft Advisory from 10 AM to 4 PM EDT Wednesday for
LMZ844>849.
&&
$$
UPDATE...WDM
SYNOPSIS...Borchardt
SHORT TERM...Borchardt
LONG TERM...MJS
AVIATION...WDM
HYDROLOGY...HLO
MARINE...Borchardt
Area Forecast Discussion
National Weather Service Nashville TN
739 PM CDT Tue Jun 12 2018
.UPDATE...
FOR EVENING DISCUSSION.
&&
.DISCUSSION...
Hrrr appears to be somewhat useful this evening, for a change.
Convective complex is spreading slowly southeastward but weakening
as the better divergence fields weaken. Momentum, however, looks
strong enough to allow for the expansion of likely trw- further
south and east. Furthermore, complex will continue to dive into
higher capes as it moves southeast. Update out shortly.
&&
.AVIATION...
00Z TAF DISCUSSION.
VFR expected unless otherwise noted. Consensus short term model
solutions, including latest HRRR showing area of convective
activity presently entering NW portions of mid state, should shift
SEWD with time but weaken. Believe main impact at CKV should be
no later than 13/01Z CKV, around 13/03Z BNA, and around 13/05Z
CSV. Will address within TEMPO groups MVFR ceilings/vsbys at
CKV/BNA as stronger shwr/tstms moves over terminals during
a two hour time period window. Convection chances should
decrease as evening hrs progress, but can still not rule out iso
shwrs at least in VCNTY. As upper level troughing becomes more
pronounced with embedded shortwave passages also, along with sfc
front approaching mid state and possibly moving into NW portions
of mid state by 13/24Z, the stage is set for sct to numerous
shwrs/tstms development after 13/15Z. Orographic diurnal influences
should enhance potential of numerous shwrs/tstms Cumberland
Plateau Region/CSV. Will go with FM group mention of VFR
shwrs/tstms CSV 13/17Z. However, with considerable uncertainties
still due to predominate nature of pulse type convection
elsewhere, will mention VCTS only.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION......21
AVIATION........31
Area Forecast Discussion
National Weather Service Shreveport LA
1001 PM CDT Tue Jun 12 2018
.UPDATE...
Made some changes to sky only at this time.
&&
.SHORT TERM...
Temperatures are in the upper 70s and low to mid 80s and doing
fairly well on the hourly gridded data. Winds are light SE at most
locales or even calm. The radar has quieted down early this
evening and as such a lot of the debris cirrus has thinned early
as well. Some of the mostly cloudy wording in some zone groups
will become partly cloudy. KSHV 88D is currently showing a few
tiny shower cells in Rusk and Panola counties with the recent
thunder in Bowie already gone. The only storm left is on the MS
river near Greenville and shows up fairly well on the HRRR along
with a blip near three states. The HRRR dries out all of the very
limited QPF in the next hour anyway. We will rerun the zones to
include new sky and the 03Z pop grid so as to remove early evening
wording. No other changes needed at this time. /24/
&&
.PREV DISCUSSION... /issued 656 PM CDT Tue Jun 12 2018/
AVIATION...
For the ArkLaTex, we are done early today with a quiet night
ahead. Light S/SW wind with MVFR cigs/vsby 13/10-16Z becoming VFR
with models hinting at more VCTS type activity from KTXK to KELD
and KMLU by late morning and early aftn. Otherwise our winds
resume S/SW 5-10KT with expected amendments and tempo groups as
radar start to light up with scattered TSTMS. Attm our climb winds
are SW10-15KT veering to NW flow aloft. Outlook is similar with
p.m. TS at varied terminals for the remainder of the work week.
/24/
PREV DISCUSSION... /issued 338 PM CDT Tue Jun 12 2018/
SHORT TERM...
Persistant upper-level weakness across the region continues to
generate scattered afternoon and evening showers and
thunderstorms areawide. Convection to diminish around sunset with
overnight low temperatures forecast to fall into the low to mid
70s. Upper-level ridge to strengthen on Wednesday with
temperatures forecast to climb into the low to mid 90s across much
of the region. However, enough instability should exist across
southern Arkansas and northeast Louisiana from remnant weakness to
again support scattered showers and thunderstorms across these
areas with high temperatures forecast to climb into the lower 90s.
Otherwise, low-level moisture trapped beneath diurnal inversion
could generate widespread stratocu ceilings around daybreak each
morning. /05/
LONG TERM.../Thursday through Tuesday/
On Thursday, the upper ridge, which has dominated our weather for
the last week, will continue to slowly migrate northeast into North
Texas and Oklahoma, while also expanding eastward slightly. The
increased subsidence in the center of the ridge should help to keep
any chances for convection confined to areas of a line from DeQueen
AR to Lufkin TX. With the center of the ridge moving north of the
area on Friday, this will allow mid-level moisture from the Gulf of
Mexico to stream northward into the region as deep southerly flow
returns. This should help to increase the coverage of diurnal
convection Friday, especially across Louisiana and Southern Arkansas.
For Saturday and beyond, a mid-level trough will move into the
northwest Gulf of Mexico on the southern periphery of the upper
ridge. As the ridge moves eastward towards the Ohio River Valley,
this should steer the trough northward through Central Texas and
towards the Southern Plains. This will result in a gradual increase
in convection across the entire area beginning on Saturday.
Convection will likely be widespread Sunday and Monday before
becoming more confined to the northwest half of the area on Tuesday.
Best rain chances and greatest coverage of showers and thunderstorms
will continue to be during peak daytime heating, but scattered
convection should persist into the overnight hours.
There is still considerable uncertainty in the forecast after
Friday, so potential rainfall amounts are difficult to determine.
However, medium range models have been fairly consistent over the
last couple of days advertising these rain chances. Despite the
uncertainty surrounding the rainfall, the associated increase in
cloud cover combined with the rain should bring daytime high
temperatures below 90 degrees F for the beginning of the next work
week.
CN
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 76 94 74 94 / 40 10 10 20
MLU 75 90 73 92 / 40 30 20 30
DEQ 72 92 71 94 / 30 30 10 10
TXK 75 91 74 94 / 30 20 10 10
ELD 74 88 72 93 / 40 40 20 20
TYR 75 93 73 94 / 20 10 10 10
GGG 75 94 73 94 / 30 10 10 10
LFK 74 95 72 93 / 20 20 10 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
24/05/09