Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/02/18
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1028 PM CDT Fri Jun 1 2018
.UPDATE...
Issued at 1027 PM CDT Fri Jun 1 2018
Allowed the High Wind Warning to expire. Showers have filled in
over eastern SD and outflow winds have diminished as a result. An
further strong wind gusts are expected to be confined to within
the vicinity of thunderstorms this evening.
UPDATE Issued at 642 PM CDT Fri Jun 1 2018
Forecast is on track this evening with a swath of storm occurring
in north central SD and spreading south and east. Still some
question as to coverage as the system treks east, but will leave
pops as they are for now.
&&
.SHORT TERM...(This Evening through Saturday)
Issued at 134 PM CDT Fri Jun 1 2018
Forecast challenges this afternoon through Saturday afternoon
mainly revolve around severe thunderstorm chances from late this
afternoon through late tonight.
Currently, skies are partly to mostly sunny and temperatures are
warming through the 80s, and in some areas into the 90s. Winds are
strong from the southeast at 15 to 30 mph with gusts up to 45 mph.
Per "right now" upper air analysis, there remains a mid-level warm
air capping inversion (EML) of +11C to +13C at 700hpa over western
SoDak, although a ribbon of 3500+ J/kg of ML CAPE has already
developed up into western/swrn SoDak. A discernible short-wave is
now showing up on water vapor imagery (far nern corner of CO) moving
north-northeastward toward the northern plains region. Attached to
it, the Rap Refresh model has a 70knot speed max aloft also lifting
into Nebraska and South Dakota, with the left exit region aligning
over a lee-side trof positioned across south central South Dakota.
Some agitated cu/initial updrafts appear to be developing over that
area as well. Effective deep-layer bulk shear values of 40+ knots
still reside across eastern Wyoming and Montana. The surface cold
frontal boundary of interest is currently situated from near the
Montana/North Dakota border down into northern/northeastern Wyoming,
with a lee-side trof/pseudo warm front extending down from near
Buffalo, SD to between Chadron and Valentine, NE.
Later this afternoon and evening all these features are progged to
translate over into western and central South Dakota. There is that
area of agitated CU in south central South Dakota, but still
thinking convection should begin initiating, in earnest, between 4
PM CDT and 7 PM CDT along or perhaps just west of the Missouri River
valley. Discrete supercells are expected, initially, with a range of
severe weather types ranging from large hail and damaging winds, to
perhaps an isolated tornado or two. Although, LCL heights may end up
being just a tosh too high to support tornadoes this afternoon.
After 7 PM CDT, the threat area begins to move over toward northeast
South Dakota/west central Minnesota. The potential storm mode begins
to change-over to something more like one or more line(s)/broken
line(s) of storms with the severe threat becoming more of a damaging
wind concern. 0-3km shear vectors (25 to 35 knots) off the Rap13
model do support some potential for qlcs meso-vorticity generation
this evening, should a situation where sufficient cold-pool/shear
interaction can be had. Convection should be exiting the far eastern
zones by early Saturday morning. At that point, the cold front is
well gone, too, leaving the whole forecast area in breezy to windy
northwest winds and temperatures a solid 10 to 20 degrees cooler for
the first half of the weekend.
.LONG TERM...(Saturday Night through Friday)
Issued at 134 PM CDT Fri Jun 1 2018
The period begins with the upper level pattern transitioning from
northwest flow on Sunday to ridging by Monday. The building ridge
will bring above normal temperatures into the region, with highs
reaching the mid to upper 80s Monday and Tuesday. Dry conditions are
expected from the second half of the weekend through at least
Tuesday. Shortwaves crossing the region Wednesday through Friday
will bring scattered showers and thunderstorms into the area. Even
with the threat for thunderstorms, temperatures Wednesday through
Friday should remain above average.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday Evening)
Issued at 642 PM CDT Fri Jun 1 2018
VFR conditions are expected except in the vicinity of
thunderstorms. Showers and thunderstorms will move east this
evening and will affect all taf sites. Gusty southeast winds will
persist before shifting to the northwest on Saturday. Winds will
be strong and erratic near thunderstorms and outflow boundaries
this evening.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...Wise
SHORT TERM...Dorn
LONG TERM...SD
AVIATION...Wise
Area Forecast Discussion
National Weather Service Wakefield VA
1045 PM EDT Fri Jun 1 2018
.SYNOPSIS...
A very moist and unstable airmass will remain in place through
the weekend. A weak frontal boundary will approach from the
northwest this evening into tonight. Low pressure develops along
the mid-Atlantic coast on Saturday, then lingers nearby through
Sunday, before lifting northeast on Monday.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
As of 1045 PM Friday...
Ongoing cluster of showers and thunderstorms riding along
moisture convergence boundary, mainly over central/south
central VA. Convection should taper off over the next few
hours, with showers tapering off shortly thereafter. Past few
runs of the HRRR and the incoming 00z NAM showing a bit quicker
with showers re- developing as moisture pools along the boundary
to the north as low pressure comes together Saturday morning.
Will therefore hang on to at least a low chance for showers for
all but NC counties through the overnight. Once again warm and
humid conditions. Lows tonight mainly 70-75.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
As of 355 PM Friday...
The weekend is not shaping up to be very nice. The aforementioned
upper trough over the eastern lakes/OH Valley is expected to
become cut off from the mean upper flow over the mid-Atlantic
region by late Saturday and linger overhead/nearby on Sunday.
This will set the stage for increasing rain chances through Sat
morning, then widespread showery conditions with a chance of
thunderstorms with the sfc cold front still moving south through
the area in the afternoon. Have PoPs increasing to likely
(55-70%) across the NW 1/3 of the CWA by midday Sat, then likely
to categorical PoPs (65-85%) all areas after 18z. Highs in the
80s. Continued showery Sat night. Lows 65-70. Sunday looks to be
unsettled and rainy, especially for those points along/north of
I-64 and across the eastern shore as the models suggest the sfc
low will stay nearly stationary around the lower Chesapeake
Bay. In fact, the NAM suggests temperatures will struggle to
rise out of the 60s for the northern part of the forecast area.
Highs from the upr 60s/low 70s north to around 80 south. Have
increased to likely PoPs (55-70%) most areas, except chc PoPs
(40-50%) in NC. Places close to the coast, especially north of
Cape Charles, look to be breezy to windy Sunday with the NE
winds associated with the low to the south. Due to the moist
airmass in place, the overall threat of severe storms will
remain low through the weekend. However, there will still be the
potential for localized flooding downpours, especially later
Sat.
By Monday, things should improve as the low gets kicked
offshore and heads NE to New England. WNW flow aloft coupled
with N winds at the sfc should give us dry conditions and
lower/more comfortable dewpts. Clouds should also break for
some afternoon sunshine. Highs 75-80.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 355 PM Friday...
The low pressure system that will impact the CWA this
weekend is projected to be well offshore by late Monday. Thus, the
extended period will actually start out with dry weather for a
change. Another upper low (coupled with sfc low pressure)
drops SE from southern Canada to the northeastern US from
Tue-Thu AM. This will lead to another chance of showers/t-storms as
the associated cold front approaches the CWA by the middle of
next week. However, the latest 12z GFS and ECMWF continue to have
differences in terms of timing. The ECMWF is the faster model as it
brings the front through (with isolated showers/t-storms) Tuesday
night. The GFS is slower and brings the front (along with
more widespread showers/t-storms) through Wednesday night.
Due to the differences in the guidance, decided to keep PoPs no
higher than 30% through Wednesday night. It should remain mostly dry
on Thursday and Friday (with perhaps an isolated shower/t-storm in
far southern/western portions of the CWA) as sfc high pressure
builds in from the north.
Milder weather expected Tuesday through Thursday with highs around
80 degrees and lows in the upper 50s to lower 60s. Warming up
slightly on Friday with highs in the mid to upper 80s.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
As of 825 PM Friday...
VFR conditions across area terminals this evening, with some
Locally sub-VFR conditions west of terminals in sct convection.
These t-storms will move east over the next few hours before
weakening between 01 and 03z this evening. Went ahead and
included VCTS for RIC from 21-01z, but not enough confidence for
any mention of thunder at the other terminals, and have opted
for vicinity SHRA wording instead at ORF/PHF/SBY this evening.
Brief IFR visibilities are possible in any t-storm. Dry
conditions and VFR ceilings are expected late tonight with
another period of Flight restrictions likely from late morning
through the aftn Sat w/ showers/t-storms likely at all
terminals ahead of a cold front.
Outlook: Widespread showers look likely on Sunday as developing
low pressure stalls just off the mid Atlantic coast. Gusty NE
winds to ~20 kt are also possible (most likely at SBY) on
Sunday. Flight restrictions are likely from Sun-Sun night as the
area of low pressure slowly moves offshore. Dry weather (with
likely VFR conditions) finally returns on Monday.
&&
.MARINE...
As of 355 PM Friday...
Generally quiet again this aftn with SSE winds 5-10 kt on avg,
shifting to the SSW at around 10 kt later this evening. The only
concern will be for scattered tstms later this evening/overnight and
locally higher waves/seas/winds will be possible in any tstms that
do develop. Otherwise outside on convection, Seas avg 2-3 ft and
waves in the Bay/rivers main around 1 foot, except 1-2 ft in the
upper Bay and at the mouth of the Bay.
By Sat, a cold front will be situated just N of the region will
slowly cross the waters into Sunday. Models remain a bit at
odds with the pattern Sun into Mon, but are generally coming to
a consensus that strong E/NE winds will develop/prevail on
Sunday across the northern waters (especially northern ocean
waters). While there is some potential for a low-end Gale event,
the sfc pattern depicts only about a 1020 mb sfc high to the
NE, so the probability for Gales looks less than 50% and
therefore did not issue a Gale Watch. Farther south, sfc low
will be in the vicinity and will slowly pull off the coast Sun
evening. Thus, winds will be much lighter and probably remain
below SCA thresholds until early Mon. Have seas building to 7-9
ft north of Parramore Island but only 3-4 ft in southern VA/NE
NC on Sunday. Eventually, forecast depicts a marginal N wind SCA
event for most of the marine area on Mon as the sfc low pulls
ENE off the Delmarva coast with high pressure building in from
the NW. Diminishing winds/seas through midweek.
&&
.HYDROLOGY...
As of 1045 PM Friday...
The River Flood Warning for the Rivanna river at Palmyra has
been cancelled as the water level has fallen below minor flood
stage. Will need to watch river levels on the Rivanna,
however...as latest forecast shows river going back into flood
over the weekend. Please see WBCFLSAKQ for the last statement.
&&
.TIDES/COASTAL FLOODING...
As of 530 PM EDT Friday...
Potential for minor tidal flooding with the high tide cycle late
Sunday night/early Monday morning, mainly for the Worcester MD
along the Assawoman Bay and the Ocean. At this time, appears
less likely south of this region though it may get close at
Chincoteague and Wachapreague depending on the exact track of
the low pressure system Sunday into Monday.
&&
.CLIMATE...
As of 530 PM EDT Friday...
Preliminary May 2018 climate numbers:
RIC:
* 73.4 F avg temperature (ranks as 2nd warmest). Warmest is
74.6 F/1896.
* Monthly rainfall total is 10.35" which ranks as the wettest
May on record. (breaking the old record of 9.79" in 2016).
(Precipitation records date back to 1880).
ORF:
* 73.6 F (73.596 F to be precise) avg temperature (ranks as
warmest on record). Warmest had been 73.6 F (73.565 F to be
precise)/1880.
* Monthly rainfall total is 7.68". This ranks as the 8th
wettest May on Record (wettest is 10.12" in 1979).
(Precipitation records date back to 1871).
SBY:
* 69.0 F avg temperature (ranks as 4th warmest). Warmest is
70.2 F/1944.
* Monthly rainfall total is 9.79". This ranks as the 2nd
wettest May on record (wettest is 10.38" in 1948).
(Precipitation records date back to 1906).
ECG:
* 73.9 F avg temperature (ranks as 2nd warmest). Warmest is
74.0 F/1944. (records date back to 1934).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.
&&
$$
SYNOPSIS...JDM
NEAR TERM...JDM/MAM
SHORT TERM...JDM/MRD
LONG TERM...ERI
AVIATION...ERI/MAM
MARINE...LKB/MPR
HYDROLOGY...
TIDES/COASTAL FLOODING...
CLIMATE...
Area Forecast Discussion
National Weather Service Birmingham AL
615 PM CDT Fri Jun 1 2018
.UPDATE...
For 00Z Aviation.
&&
.SHORT TERM...
Today and Tonight.
An MCS is currently pushing eastward across Tennessee with an
outflow boundary moving southward into northern Mississippi. A few
showers and thunderstorms will be possible across the far northern
counties through the morning hours along the outflow boundary, but
the stronger storms this morning are expected to remain north of the
area. This boundary is expected to stall out across the northern
counties, and then may drift northward slightly due to southerly flow
at the surface. This outflow boundary will likely serve as the key
player for convective initiation this afternoon, serving as the
forcing mechanism that was missing yesterday. The MCS is associated
with a shortwave trough in the northwest flow aloft between an upper-
level ridge over Mexico and the Southern Plains and a trough along
the East Coast. This shortwave with some convective/MCV enhancement
will provide some upper-level forcing today. 00z CAMs and the HRRR
are in fairly good agreement on convective initiation along the
boundary across our far northern counties by afternoon with storms
moving from the WNW to the ESE with 20-25 kts of 700-500mb mean flow.
Area 00z soundings sampled steep mid-level lapse rates associated
with an elevated mixed layer across the area and a pocket of 500mb
temperatures around -10C. The 00z BMX sounding indicated 700-500mb
lapse rates of 7.2 C/km, while the 00z JAN sounding had 700-500mb
lapse rates of 7.9 C/km. These steep lapse rates aloft combined with
daytime heating and a humid air mass at the surface will result in
SBCAPE values of 3000+ J/kg and MLCAPE values over 2000 J/kg with
fat CAPE profiles. This will be favorable for strong updrafts, while
DCAPE values over 1200 J/kg will be favorable for strong downdrafts
and strong to damaging winds. Microburst parameters are also in the
high to very high category. The limiting factor preventing a more
widespread/significant damaging wind threat appears to be 850-700mb
flow oriented parallel to the outflow boundary rather than
perpendicular, and capping further south, but this will be closely
monitored. Expect several clusters and bowing segments to develop.
Quarter size hail will be possible as well. Can`t rule out hail up
to golf ball size as well given the lapse rates/instability, but
limiting factors will be hot air at the surface and weak bulk shear,
so will stick with just quarter size hail in the graphics at this
time.
All in all, the SPC upgrade to a slight risk looks very reasonable
and will indicate this in our severe graphics. There`s some question
as to whether any severe storms will make it as far south as the I-
85 corridor given warmer 700 mb temperatures down there and the
westerly component to the flow. Will hold off on a threat in these
areas but monitor trends. One thing to keep an eye on will be how
far south the outflow boundary makes it this morning. If it makes it
further south than forecast, this could cause the threat to shift
further south, and perhaps decrease the threat in the Highway 278
corridor. Overall flooding threat does not look very high compared
to previous days based on PWATs and the speed of storm motions.
However, some localized flooding will be possible given saturated
soils and uni-directional 850-700mb flow which could result in areas
of training. The PoP forecast for tonight will be dependent on how
far south outflow from the afternoon convection makes it. There are
some signals for scattered showers and isolated thunderstorms
lingering through the overnight hours along an outflow boundary.
32/Davis
.LONG TERM...
Saturday through Thursday.
On Saturday, any minimal upper ridging over the Caribbean weakens
as the Eastern Conus upper trough pushes further east over the
Atlantic Seaboard. Lingering activity from Friday`s system moving
southward in the morning across Central Alabama may likely squash
our instability for during the day on Saturday. It all depends
how quickly Friday`s system deteriorates, if there are lingering
boundaries in its wake, and if we can heat up enough early on in
the day Saturday. However, at present, guidance is hinting at the
first scenario.
Step forward to late Saturday night into the pre-dawn hours on
Sunday. Another convective complex ahead of the front will move
south/southwest through the upper flow. Indications are that it
would be deteriorating in the late night hours. Also, guidance is
trending a little slower which could put the system barely entering
the northwest counties between 4 AM and sunrise depending on
model timing differences.
Along the front in the south Sunday afternoon, we could see enough
forcing with our moist environment in place for a few strong
storms and some damaging wind gusts during the heat of the day.
After the front, we dry out and cool down some for the first half
of the week. With the front stalling out along the coast, we could
see an isolated storm in the far south by Wednesday. However, for
the most part our extended is dry.
08
&&
.AVIATION...
00Z TAF Discussion.
Scattered thunderstorms will continue through the early morning
with VCTS included because of uncertainty in coverage and timing
of convection at each site. Enough moisture will be present
through the morning for IFR ceilings and fog development...with at
least MVFR visibilities at each site...and possible IFR
visibilities at sites that receive rainfall late tonight through
the early morning. Enough dry air is present on Saturday with
models agreeing that thunderstorm development will be limited.
Have left mention of VCTS or VCSH out of TAF for now...but will
update if needed.
24
&&
.FIRE WEATHER...
A northwest flow pattern will keep rain chances fairly elevated
through the weekend with scattered to numerous showers and
thunderstorms expected. The best chances will be in the
afternoon. Rain free conditions return on Monday and through the
middle of next week. No fire weather concerns at this time.
08
&&
.PRELIMINARY POINT TEMPS/POPS...
Gadsden 67 90 70 87 61 / 40 30 20 50 10
Anniston 68 88 71 88 62 / 40 40 20 50 10
Birmingham 71 90 73 89 64 / 40 40 20 40 10
Tuscaloosa 72 92 74 90 64 / 40 40 20 40 10
Calera 71 90 73 88 64 / 40 50 20 50 10
Auburn 71 87 72 89 65 / 50 50 20 50 10
Montgomery 73 90 74 90 66 / 50 50 20 50 10
Troy 72 89 73 91 65 / 50 50 20 50 10
&&
.BMX WATCHES/WARNINGS/ADVISORIES/...
None.
&&
$$
Area Forecast Discussion
National Weather Service State College PA
1051 PM EDT Fri Jun 1 2018
.SYNOPSIS...
Dry air over the Great Lakes will attempt to push southeast
into Pennsylvania tonight. It will likely stall out half way
through the Commonwealth. The upper trough linked to the cold
front will become detached from the jet stream as a cut off low
over the Mid Atlantic region Sunday. The upper low will lift out
next week ahead of an anomalous upper trough building over the
northeast conus.
&&
.NEAR TERM /UNTIL 8 AM SATURDAY MORNING/...
Heaviest rain now over Adams and Lancaster and filling in over
York. This is exactly how the CAMs from the last 1-2 hours have
been going - centering the heaviest rain there. Tropical
moisture is still present and the cap of earlier is moot. Cold
pool from earlier convection has added the lift to make it go.
The trouble appears to be the heavy rain also impinging on the
srn parts of those same counties from MD. This could shortly
lead to flooding with FFGs lowest in srn York Co, and more
headroom in Adams and Lanc Cos, but still less than 2.2"/hr.
Expect that area to get the most rain over the next 3 hrs, and
we will need to watch it carefully. Considering FFWatch for
those SErn-most Cos for the overnight.
Prev...
Convection fired all around the area where it remained
cool/stable the longest today - except in the SE - as of yet.
The cluster of storms over the scent counties is slinking away,
but has produced 1-3 inches of rain in a short amount of time.
Convection from NY also died for the most part as it moved into
the state. Cooling with loss of daylight will further detract
from the potency of the storms. However, the efficient rain
process will still leave a threat of minor flooding in mainly
the srn part of the state early tonight. Drier air not showing
up yet off to our NW, at least on this side of the ponds, as
dewpoints remain in the m60s in ERI and BUF.
Latest HRRR and RAP indicate that storms/showers may continue
through much of the night along the Mason-Dixon Line. HRRR even
suggests a flare up of convection over the Lower Susq Valley -
esp in York and Adams counties around midnight. The convergence
of storms occurring over the ern WV panhandle should stay to our
south, but will need to keep POPs high in the south and
continue to watch for isolated flooding problems.
Tweaks to temps/sky not necessary.
Prev...
Weak mid level capping inversion has been successful in
inhibiting initiation thus far this afternoon. CAMs show most
realistic development taking place along lake breeze front from
Lake Erie which is just now developing as per GOES-16 vis and
radar imagery.
Still dealing with rich subtropical moisture throughout the
area, as has been the case since Wednesday. Still expect
diurnal heating of high PW air mass to generate moderate CAPEs
over the NW and parts of the south. Convective evolution should
be close to Thu afternoon. CAMs weaken the lake breeze line as
it reaches into my CWA while any other diurnally driven
convection weakens into a larger area of light to moderate
showers after dark as it crosses central PA this evening. Weak
0-6km shear indicates convection will be pulse-type, with little
chance of organized severe weather. Given high PW, can`t rule
out isolated rainfall amounts of 2+ inches, creating localized
flooding issues. Still in MRGL outlook for excessive rain from
WPC, with SLGT risk limited to south of Mason Dixon line.
Diffuse cold front pushes southeast across the region overnight,
with gradually diminishing band of showers accompanying it. Weak
wind shift to the north will be the other impact. Mins won`t
drop off all that much, ranging from the upper 50s through the
upper 60s from north to south.
&&
.SHORT TERM /8 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
Northern and central PA should enjoy drier conditions on
Saturday as the northerly flow shunts instability and high deep
layer moisture to the south. Models track a wave along stalled
boundary south of the Mason Dixon Line...brushing the south with
low chance POPs and cloudy skies. Expect at least partial
clearing central and north. highs will generally be in the mid
to upper 70s..except low 70s over the Alleghenies.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
Model and ensemble guidance offer a reasonably similar large
scale pattern evolution over the Mid Atlantic region this
period. A cut off upper low over the Mid Atlantic on Sunday
will be absorbed by an anomalous upper level trough building
into the northeast conus the first half of next week. Under this
pattern, confidence is better than average in weather
conditions staying "unsettled" with repeated/daily rain chances
through early next week. Drier conditions appear likely by
Wednesday, as the upper trough axis passes east of Pa.
Temperatures will trend relatively cool, with the upper level
trough influence holding readings near to below average for
early June. However, a moderating trend is likely by late next
week, as upper trough begins to lift out.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
Showers will be relegated to the lower half of the state. VCTS
with brief periods of TSRA are still possible through the 08Z at
MDT and LNS. Another line of convection will be moving from the
south into Southeast PA. These storms are slow moving and are
slowing drifting to the southeast and will slowly weaken and end
by 09Z at the latest. Lower ceilings then work in again tonight
in NW/N flow. Have brought in IFR cigs to the western TAF sites,
with MVFR elsewhere. Given the moisture at the SFC and southerly
winds, IFR is possible at LNS. Cigs and vsbys will slowly
improve late tomorrow morning.
.Outlook...
Sat...AM low cigs possible Laurel Highlands and N Mtns.
Sun...AM low cigs possible, mainly KJST.
Mon...Patchy AM fog, then ceiling restrictions likely.
Tue...Patchy AM fog.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch until 8 AM EDT Saturday for PAZ064>066.
&&
$$
SYNOPSIS...DeVoir/Fitzgerald
NEAR TERM...Dangelo
SHORT TERM...DeVoir/Fitzgerald
LONG TERM...Fitzgerald/Gartner
AVIATION...DeVoir/Ceru
Area Forecast Discussion
National Weather Service Duluth MN
657 PM CDT Fri Jun 1 2018
.UPDATE...
Issued at 644 PM CDT Fri Jun 1 2018
Updated aviation section below for 00Z TAF TAF issuance.
I have also updated the sky grids for the persistent clouds that
have formed over Lake Superior and spread onshore over the
Arrowhead. Models are overly optimistic in clearing these out
overnight, and have significantly increased cloud cover overnight.
This may have other impacts, but this is the most significant
change and will make other adjustments at need.
&&
.SHORT TERM...(This evening through Saturday)
Issued at 320 PM CDT Fri Jun 1 2018
Clouds have been very slow to erode around Lake Superior and over
far northern Minnesota and it may take a few more hours for them
to diminish there.
The forecast for tonight into Saturday is still on track with
showers and thunderstorms expected to reach our western border
late tonight. Some of the storms could be strong as a low level
jet will be in place and the NAM forecasts southerly 850MB winds
around 45 knots. The RAP does have MUCAPE to 1000 J/kg over KBRD
late tonight, which may be a bit high but enough CAPE should be
available to maintain strong storms into our western areas late
tonight/early Saturday morning. Showers and a few storms will
spread east through most of the Northland on Saturday. It will be
a cool day with highs in the forties close to Lake Superior and
lower fifties to lower sixties inland. Temperatures will cool as
the rain moves in. Moisture will be plentiful with PWAT values
around 1.3". This combined with strong forcing will result in
rainfall amounts through Saturday night from three quarters of an
inch to around one inch over much of the Northland. There will
likely be localized areas greater than an inch, possibly leading
to localized flooding.
.LONG TERM...(Saturday night through Friday)
Issued at 320 PM CDT Fri Jun 1 2018
A cold front will finish moving through the Northland Saturday night
from west to east. This front will spread rain through the
Northland, and there may be just enough forcing for thunder.
Otherwise, the lack of instability will mean this will mostly be
rain.
Cool and drier air will move into the Northland Sunday in the wake
of the departing front. Widespread wind gusts of 20 to 30 mph are
forecast because of deep mixing. There will likely be
scattered/broken cumulus cloud cover and some showers, especially
across the eastern forecast area earlier in the day, before more
plentiful sunshine develops by the late afternoon. Highs should be
in the lower 60s to near 70 degrees.
High pressure will likely move through the Northland Sunday night
and Monday, meaning a period of clearer weather. However, the GFS
sets up a stationary front near or just south of the forecast area
and triggers showers and storms from central MN to northwest WI in
the evening. On the other hand, the European and Canadian models are
maintain the clear weather. Therefore, just have low precipitation
chances at this time to account for the GFS.
There is greater uncertainty Tuesday and beyond, but it at least
looks like warmer than normal weather will return to the region. The
GFS suggests more thunderstorms from central MN to northwest WI
Tuesday afternoon and evening with the stalled/cold front, but the
European and Canadian keep the region dry with the high pressure.
The latter models then suggest low pressure will finally move
through the region Tuesday night or Wednesday and bring a
possibility of showers and storms, while the GFS has high pressure
over the region at that time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 644 PM CDT Fri Jun 1 2018
East flow off Lake Superior has generated stratus for KDLH, KHIB
and KINL to a lesser extent. Models are being overly generous in
clearing these clouds from the terminals by 06z tonight, but this
is unlikely with the strong east wind off the lake. Have kept all
three sites pessimistic, with IFR ceilings. KINL and KHIB may
break out on the 04z-07z time range, but KDLH is likely to remain
in the clouds until at least 10z if not later. I do not currently
have KBRD and KHYR getting any of this stratus, but that may
change. A band of rain with IFR ceilings and visibilities is
expected to move across the terminals beginning around 09z, slowly
spreading east through the remainder of the TAF period. Thunder is
possible at the terminals, but have kept most of them to VCSH/VCTS
for now.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 41 50 42 66 / 0 100 60 10
INL 46 57 45 65 / 20 100 60 10
BRD 50 61 49 72 / 70 100 30 0
HYR 47 67 48 69 / 0 100 70 10
ASX 40 58 44 67 / 0 80 80 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...Beach Hazards Statement until 9 PM CDT this evening for WIZ001.
MN...Beach Hazards Statement until 9 PM CDT this evening for MNZ037.
LS...Small Craft Advisory until 10 PM CDT Saturday for LSZ121-144>148.
Small Craft Advisory from 4 AM to 10 PM CDT Saturday for
LSZ140>143.
&&
$$
UPDATE...LE
SHORT TERM...Melde
LONG TERM...Grochocinski
AVIATION...LE
Area Forecast Discussion
National Weather Service Des Moines IA
637 PM CDT Fri Jun 1 2018
.DISCUSSION.../Tonight through Friday/
Issued at 300 PM CDT Fri Jun 1 2018
Much of the region remains under the influence of an amplified
pattern, with hot conditions present underneath a building ridge
and a deep upper level low over the northern Rockies. Much of the
state is experiencing another day in the low to mid 90s with
relatively weak and disorganized flow at the surface. Strong
southerly flow ahead of the upper level low has advected a highly
unstable airmass northward over much of the central and northern
Plains. Severe weather is likely as deep convection initiates
this afternoon and evening in a zone of enhanced frontal
convergence in central NE/SD. The threat for severe weather shifts
eastward toward the Missouri River Valley late this evening
and overnight as the storms track southeast along an instability
axis and congeal into an organized linear structure. Uncertainty
remains as to the extent of the severe weather threat in our area
overnight. Most HREF members keep the favored corridor of
instability down through southeast NE into northwest MO.
Meanwhile, the NAM/HRRR/ESRL HRRR bring the strong instability and
potential for severe weather further north into southwest Iowa.
Steep mid-level lapse rates and enhanced deep layer shear would
support a threat of some hail and damaging wind gusts, especially
if the system can remain surface based and maintain a balanced
cold pool.
Regardless of the severe weather threat showers and storms are
likely across much of the area overnight through tomorrow morning
as deep layer ascent increases with the approaching upper level
trough. Another round of showers and storms materialize Saturday
afternoon as a cold front is forced through the state. Cloud cover
and recovery issues behind the morning convection raise questions
with respect to the strength and spatial extent of the later day
activity, but at this time areas east of east of I-35 stand the
best chance to see precipitation.
Sunday looks quiet pleasant as surface high pressure settles into
the area and highs closer to seasonal normals in the 70s to low
80s. Above normal temperatures expected to return by Tuesday and
through much of next week as another ridge builds over the
Plains. Increasing moist southerly flow over the latter half of
the week will promote daily slight/low chance PoPs, but these
some of these periods should be dry as models get a better handle
on the timing of weak waves rounding the top of the ridge. Some
degree of severe weather risk will likely exist during this
period, but weak flow aloft will be a mitigating factor as the
ridge aloft forces the main jet stream north of the area.
&&
.AVIATION.../For the 00Z TAFS through 00Z Saturday evening/
Issued at 637 PM CDT Fri Jun 1 2018
Quiet weather will persist this evening however thunderstorms will
move into western Iowa late tonight and spread east into Saturday
morning. These will bring gusty and variable winds along with
restrictions to visibilities and ceilings in and around the
thunderstorms. These storms are expected along and ahead of a cold
front which will move east across central Iowa on Saturday. Most
of the storm threat will end by the finish of the forecast period
with widespread VFR conditions along with increasing northwest
surface winds on the backside of the front.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
DISCUSSION...Martin
AVIATION...Cogil
AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
628 PM CDT Fri Jun 1 2018
.Discussion...
Issued at 318 PM CDT FRI JUN 1 2018
Upper level ridging and slight WAA in the low levels allowed for
abnormally warm temperatures in the lower 90s to develop over the
area this afternoon. The high mixing level today allowed the
dewpoint to lower and at least keep us somewhat marginal on the
humidity levels and heat index values. The next major impact to the
region will start to spin up late this afternoon over central
Nebraska as very unstable air meets up with moisture and a shortwave
trough & frontal boundary to initiate convection in that area.
The overall trend in the model guidance is for the storms over
central Nebraska to quickly become linear along the convergence
boundary ahead of a cold front progressing east. The strong
southerly flow over the central plains today has developed a large
swath of MLCAPE values >4000 J/kg and SBCAPE to near 6000 J/kg
that spans from eastern Oklahoma up through central Nebraska. As
the upper level shortwave progresses east, a surface low will
develop over central Kansas propagating this high region of CAPE
to the east. As the sunsets, the surface layer will become
decoupled allowing the LLJ to intensify over central Kansas. The
LLJ will shift slightly to the east allowing MUCAPE of near 5000
J/kg all the way to the KS/MO border. The strength and orientation
of the LLJ shows backwards propagating corfidi vectors orientated
to the SE at 30kts. Once this complex of storms develops a solid
cold pool, this system is expected to take a hard southerly turn
and feed off that LLJ and 4000+ MUCAPE along with mid level lapse
rates near 9C/km. The MCS will rapidly push into our CWA after
06z, with a high likely of severe winds 60+mph, especially as it
enters over NW Missouri. There is some uncertainty to the exact
timing of the squall line with the HRRR and RAP really struggling
to propagate this MCS southward. The latest HRRR run (18Z) is
starting to come in line with the NAMnest, HWR NSSL, and HWR NMMB
models which have been rather consistently showing a quick moving
MCS propagating to the south. All models do indicate that the MCS
will weaken slightly before reaching the KC metro area around
3-5AM, but caution should be taken when this much instability and
forcing available as this feature enters the region. A large
stratiform precipitation region can be expected to lag behind this
system keeping precipitation in the area through late morning,
also inhibiting afternoon redevelopment over central MO with cloud
coverage and rain early in the day. It is becoming more likely
that this MCS will stabilize our CWA tomorrow as it pushes through
in the morning, but if the cold pool is not able to overtake
areas of central Missouri there could be redevelopment along the
cold front as it pushes through Saturday afternoon. The current
thinking is that this stable air will hold out and any
redevelopment will occur east and south of our CWA late in the
afternoon. Dewpoint temperatures will noticeable drop on the
backside of this frontal boundary allowing Saturday night to feel
rather nice compare to what we have seen lately.
Sunday through Monday look to be two of the nicest days in the last
month on the backside of the cold front as high pressure builds
into he region. Highs will top out around the mid 80s with
dewpoint temps in the mid 50s! High pressure will start to advect
east allowing a southerly return flow to redevelop Tuesday with a
slight increase in temps and dewpoints from Monday. Wednesday we
return to our "July" pattern with a strong push of WAA and moisture
bringing low 90s and heat index values in the mid to upper 90s with
it.
&&
.Aviation...(For the 00Z TAFS through 00Z Saturday Evening)
Issued at 623 PM CDT FRI JUN 1 2018
A strong to severe line of storms is likely to move through the
entire area during the overnight hours from northwest to
southeast. Flight conditions while the leading portions of the
storms move through will likely fall to IFR with poor visibility
due to winds and heavy rain. Ceilings will also begin to drop to
MVFR behind the leading portion of the line and there should also
be embedded lightning within the trailing area as well through
early morning hours. A cold front is expected to sweep through the
area by Saturday afternoon, shifting winds to the north and
clearing skies out.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
Discussion...Barham
Aviation...CDB
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
651 PM CDT Fri Jun 1 2018
.AVIATION...
VFR conditions are prevailing at the present time and will continue
through the evening hours. MVFR/IFR ceilings can be expected once
again this morning at the I-35 sites before dissipating around 16z.
Ceilings will be getting close to Del Rio but will just mention
scattered low clouds for now. Otherwise, southerly winds will
continue through the period.
&&
.PREV DISCUSSION... /ISSUED 247 PM CDT Fri Jun 1 2018/
SHORT TERM (Tonight through Saturday Night)...
The Subtropical Ridge continues over our area with a southerly lower
level flow maintaining a pattern of night and morning low clouds
followed by afternoon sun. An upper level trough moving east across
the northern states drags a cold front south across Texas Saturday
into Saturday night. As the front approaches our area, compressional
warming is expected with highs a degree or two warmer. The ARW brings
the front and isolated showers and thunderstorms into northern parts
of the Hill Country Saturday evening. However, will go with the model
consensus as strong heating and unfavorable flow aloft make for a
slower frontal progression into only West Central and North Central
Texas. Have gone 10s for POPs with no mention for the northern Hill
Country into Central Texas for Saturday evening. Also, although not
mentioned, occasional runs of the HRRR bring isolated showers into
western Val Verde county this evening.
LONG TERM (Sunday through Friday)...
The Subtropical ridge continues overhead through the long term,
though the axis could shift north of our area late next week. The
front finally moves into our area on Sunday, then dissipates on
Monday. Frontal convergence and lift combined with peak heating
suggest the capping inversion could break to allow for isolated
showers and thunderstorms to develop over our area on Sunday and
possibly on Monday. There is a potential for strong wind gusts with
any thunderstorm. Expect only a slight cooldown with the front,
however, downburst winds with any thunderstorm should bring cooler
temperatures during late afternoon into evening hours where they
develop. Otherwise, well above normal temperatures continue through
the long term.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 75 99 76 97 73 / 0 0 10 20 20
Austin Bergstrom Intl Airport 75 98 74 96 71 / 0 0 - 20 20
New Braunfels Muni Airport 75 100 74 97 72 / 0 0 0 20 20
Burnet Muni Airport 74 98 74 93 70 / 0 0 10 10 10
Del Rio Intl Airport 77 103 77 101 77 / 0 0 0 10 -
Georgetown Muni Airport 75 99 75 95 70 / 0 0 10 10 10
Hondo Muni Airport 74 101 73 100 72 / 0 0 0 20 20
San Marcos Muni Airport 75 99 74 97 72 / 0 0 0 20 20
La Grange - Fayette Regional 76 98 75 96 72 / 0 0 - 20 30
San Antonio Intl Airport 76 100 76 99 74 / 0 0 0 20 20
Stinson Muni Airport 76 102 75 100 74 / 0 0 0 20 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Mesoscale/Aviation...Hampshire
Synoptic/Grids...TB3
Public Service/Data Collection...Williams
Area Forecast Discussion
National Weather Service Grand Forks ND
914 PM CDT Fri Jun 1 2018
.UPDATE...
Issued at 913 PM CDT Fri Jun 1 2018
Made some adjustments to pcpn chances tonight, as a lot of the
latest CAM guidance continues to show the line to the west almost
splitting in two as it approaches the Red River Valley later
tonight. The end result was lowering pcpn chances in some areas
with the expectation that pcpn tonight will not be widespread, but
more hit and miss again. As is usually expected in convection,
amounts will also be highly variable. As it looks right now, the
Devils Lake region will get the most through mid to late evening,
before the storms weaken more as they move east.
&&
.SHORT TERM...(This afternoon through Saturday)
Issued at 336 PM CDT Fri Jun 1 2018
Diffluent southwest flow aloft has developed into the Northern
Plains ahead of negatively tilted trough currently centered over
western Montana. Surface low pressure extends across the eastern
Dakotas and east to southeast BL flow is feeding higher low level
moisture into the region (highest further east). Based on SPC RAP
mesoanalysis, mixed layer is currently capped in our CWA though
we have started to destabilize over our far southwest with breaks
in mid/low clouds (ML CAPE 500-1500 J/KG). RAP with support of
VAD wind profiles indicates LLJ development and with strong
veering we have effective shear values 40-45kt in our west-
southwest.
As the negatively titled trough pushes across North Dakota this
evening/overnight upstream thunderstorm activity should "congeal"
into a linear MCS or several linear clusters. Better instability
in the evening remains east, but our western CWA (west of Red
River) should have enough instability and very strong shear to
help maintain a wind dominant severe threat. By time any activity
gets to our central CWA there should be a decreasing trend in
intensity as it moves into a much less unstable environment.
Better instability early on may support a large hail threat, but
overall main impact should be wind and even this threat could be
minimized as the activity rapidly become elevated/cold pool
dominant further east.
Some CAMs are showing possible bowing or surging segments in our far
west and this does raise a concern for possible QLCS tornado
potential considering high shear and possibility for 0-3km bulk
shear vectors remaining orthogonal to liner segments. This would
mainly be in our far west.
Main trough axis doesn`t completely transition out of North Dakota
until late Saturday afternoon, and very moist air mass with WAA/LLJ
along/ahead of this will continue to support periods of
showers/embedded thunderstorms. High PWATs tonight and Saturday
will support locally heavy rainfall, and much of our CWA should
see at least 0.5" or more of rainfall by Saturday afternoon.
Localized flood threat can`t be ruled out tonight, but storm
motions should be enough to limit this threat.
Other concern will be winds just with the trough and cold front
passage, particularly on Saturday afternoon. Depending on
mixing/momentum transfer we may see gusts approach advisory
criteria (45 mph or higher) and this will need to be monitored.
.LONG TERM...(Saturday night through Friday)
Issued at 336 PM CDT Fri Jun 1 2018
Sun-Mon: Saturday evening winds will diminish as the boundary
layer begins to decouple and surface inversion builds. Low
temperatures will dip into the 40s with coldest temperatures aloft
associated with the upper level trough moving over the area. Not
expecting frost potential as temperatures should remain warm
enough and a breeze lingers throughout the night. Sunday may be
another breezy day, although the surface gradient will slacken
compared to Saturday. Some clouds may linger into northwest
Minnesota limiting high temperatures from reaching deep into the
70s due to a upper level low in western Ontario. An effective
thermal and moisture boundary will bisect the region in a
northwest to southeast orientation in the wake of the dry airmass
left behind Saturday`s cold front. Depending on where this
boundary sets up and the strength of high pressure over the region
will dictate precipitation chances late Monday. GFS sparks
precipitation as a result of overrunning of higher moisture
content on the nose of a nocturnal low level jet forming over the
Central Plains. The drier NAM and Euro shunt the boundary more
towards the southwest favoring high pressure over the region.
Should the boundary remain further east, still not expecting
precipitation during the day Monday due to strong capping and
little forcing mechanisms.
Tues-Fri: Regardless of overnight convection Monday, Tuesday holds
shower and thunderstorm chances with the approach of a cold
front/surface trough from the northwest. The GFS is progressive with
this front and its parent mid level shortwave trough while the Euro
delays the trough`s approach stalling the surface trough. This
governs precipitation chances Wednesday as the GFS kicks a second
shortwave through a flattening upper level ridge into the western
Canadian Plains keeping conditions dry for North Dakota, whereas the
Euro moves its second shortwave trough closer over the region and
surface cyclogenesis develops over Tuesday`s stalled surface trough.
Additional shortwave troughs move through the flow of a developing
central CONUS upper anticyclone late next week. This will keep
shower and thunderstorm chances in the forecast late next week.
Temperatures will likely be above normal due to this building upper
ridge and increasing thicknesses with highs in the 80s and lows in
the 60s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 644 PM CDT Fri Jun 1 2018
Thunderstorms and gusty winds are the main story for the TAFs.
There are some gusty east winds now which should remain up
tonight, then becoming really gusty on Saturday, especially at
KDVL. As for TSTM chances, not really expecting severe storms at
any of the TAF sites, but will continue to monitor and adjust as
needed. Tried to throw in the best timing ideas for these storms,
reaching KDVL around 8-9 pm, KGFK/KFAR around 05z, and later to
the east. Model guidance has also brought in some MVFR ceilings
late tonight into Saturday. Not super high confidence in that, but
will follow that route for now.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Godon
SHORT TERM...DJR
LONG TERM...CJ
AVIATION...Godon
Area Forecast Discussion
National Weather Service Green Bay WI
1052 PM CDT Fri Jun 1 2018
Updated aviation portion for 06Z TAF issuance
.SHORT TERM...Tonight and Saturday
Issued at 302 PM CDT Fri Jun 1 2018
Clouds should dissipate over most of the area this evening as dry
air arrives from the northeast. Some of the models suggest that
clouds will return to the lakeside counties later tonight but
think that they will not. Lows should be about five degrees lower
than normal.
Saturday will start out with sunshine, but middle and high clouds
will arrive from the west in the afternoon as a cold front
approaches. Some showers or thunderstorms could make in to central
and northcentral Wisconsin during the afternoon but eastern
counties should remain dry until evening. Highs will be a bit
cooler than normal in most places.
.LONG TERM...Saturday Night Through Friday
Issued at 302 PM CDT Fri Jun 1 2018
Models still in decent agreement showing a mid-upper level trough
and associated cold front swinging across the region Saturday
night into Sunday morning, spreading a large area of rain across
the entire area. Most locations look to get 0.50-1.00" of rain,
with a few higher totals possible. Models continue to show little
to no instability to work with, but with the strength of the
shortwave and mid-level lapse rates of 5-6 C/km, can`t rule out
some embedded thunder, mainly in the evening.
As the trough and front exit the area on Sunday, showers will end
from southwest to northeast. GFS has trended toward the more
consistent ECMWF, showing the trough progressing far enough to the
east to keep most of the area dry Sunday afternoon, but the GFS
still lingers some showers over the east. Still favor the ECMWF,
but did include some POPs over the east to cover any showers
associated with the departing trough and lingering moisture within
the cyclonic flow.
GFS still seems to be an outlier as it relates to where the
closed/stacked low will reside on Sunday night into Monday.
ECMWF/Canadian continue to show it located north of Lake Huron,
while the GFS shows it moving from Lower Michigan Sunday night
into southern Lake Huron and weakening on Monday. Will continue to
lean toward the ECMWF and stick with a dry forecast. Monday could
be a windy day with an impressive wind profile in place (40+ kts
above 5000-6000 ft). Gusts between 20 and 30 mph look likely, and
if we can mix over 5000 ft, higher gusts will be possible.
Models agree on the overall synoptic pattern for next week, with
a large ridge building across the Plains. But models differ on on
location/timing of surface features/boundaries and weak shortwaves
riding through the zonal flow over the northern U.S, and where a
stronger shortwave will track on the eastern side of the ridge
mid-week. This continues to make it difficult to add any
significant detail regarding precip chances or a period to
highlight.
Slightly below normal temps are expected on Sunday behind the
cold front and under northwest flow, then a return to above normal
temps looks likely for the first half of the new week. A return
to some 80 degree weather looks possible mid-late week, but will
depend on how far north the ridge builds and if/where any
cloud/shower/storm activity occurs.
&&
.AVIATION...for 06Z TAF Issuance
Issued at 1049 PM CDT Fri Jun 1 2018
Low clouds with MVFR ceilings have expanded in coverage and pushed
WWD into eastern Wisconsin. The RAP appears to have a decent
handle on the cloud trends based on its 925 mb RH progs. That
suggests the clouds will advance across the remainder of the
forecst area overnight before maybe mixing out tomorrow morning.
Updated current 00Z TAFs suite to be more aggressive with the low
clouds a while ago, and will continue to trend in that direction
with the 06Z TAFs.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....RDM
LONG TERM......Bersch
AVIATION.......Skowronski
Area Forecast Discussion
National Weather Service Wilmington NC
905 PM EDT Fri Jun 1 2018
.SYNOPSIS...
Temperatures will remain hot through the weekend. Scattered
showers and thunderstorms may increase in coverage ahead of a
cold front moving into the area Sunday. Drier and more
seasonable air will follow next week as high pressure gradually
builds into the Carolinas.
&&
.NEAR TERM /THROUGH SATURDAY/...
As of 900 PM Friday...Convection has peaked in intensity across
the SC Midlands and is weakening as it drifts into the
Sandhills. Latest HRRR trends indicate a bit more potential for
measurable rain across the Hartsville, Darlington, and
Bennettsville area, and I`ve bumped PoPs up to 40 percent here.
Drier mid-level air plus a strengthening nocturnal inversion
should both work to further weaken the convection as it moves
eastward. No changes elsewhere. Discussion from 645 PM
follows...
Only minor changes were made to the forecast with
this evening update. Convection firing in several clusters
across north GA and the western Carolinas is shown by most
models to gradually weaken as it approaches the Pee Dee region.
Linear motion estimates place the leading edge of the convection
near Hartsville and Bennettsville around 930 PM, and I`m
maintaining a 30 percent chance of scattered thunderstorms in
the forecast here. With the nocturnal inversion expected to
deepen with time, convection should have little success
surviving beyond Interstate 95, and I`ve placed my forecast 20
PoP line from Kingstree to Marion to Lumberton. Locations east
of this line should remain dry overnight, although convective
debris clouds may make skies overcast for several hours between
9 PM and midnight. -TRA
Discussion from 300 PM follows...
West to southwest breeze has kept seabreeze pinned to the coast
with some cu developing along it. Otherwise, it was a quiet,
but hot afternoon. The downslope component to the flow has
helped to produce a very warm day with limited convection across
the area.
A potent mid to upper level trough reaching into the Carolinas
early this evening and associated sfc based trough will
continue to shift east through tonight. This will back winds to
the SW through this evening. HRRR continues to show any deep
convection to the west, enhanced by the shortwave energy there,
moving toward our local forecast area late this evening. These
shwrs/tstms will be steered by the deep westerly flow aloft,
dampening out as they move east, as we lose daytime heating,
leaving only a chc of a shower reaching the I-95 corridor and
less of chc of it making it to the coast. Expect more in the
way of scattered lower clouds and convective debris clouds
tonight. This is evident in moisture profiles and sounding data
showing a decent layer of moisture between 15k and 25k ft
tonight. The pcp water values which were down to 1.6 inches this
afternoon will spike up late this evening to 1.9 inches as
upstream convection or convective debris clouds makes their way
across the area. The pcp water will drop once again by morning
back down near 1.5 inches. Moisture profiles show only very
shallow moisture by daybreak, with limited fog potential. Expect
another warm night with temps in the mid 70s for overnight lows
in most places.
Another hot day for Saturday with increasing chc of shwrs/tstms.
A very warm and humid air mass remains in place through
Saturday in a deep westerly downslope flow. The 850 temps remain
between 17 and 18c with dewpoint temps still running between 65
and around 70. Temps will reach up into the lower 90s with
heat index values approaching 100 once again. The westerly flow will
keep sea breeze pinned to the coast again and help provide plenty of
sunshine.
The mid to upper trough will shift eastward on Sat helping to
enhance convection across the local area, mainly later in the day.
The forcing initially will be limited similar to today with main
focus of convection along sea breeze boundary, but as the trough
shifts eastward toward our area as the day progresses, it will drag
sfc trough eastward ahead of a cold front. This will shift the focus
of convection inland through the afternoon as peak heating occurs.
CAPE values reach over 2000 J/KG as pcp water increase back up above
1.8 inches. Looks like best convective activity will come just after
the near term period, heading into Sat eve.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 300 PM Friday...Initially a mid level low will be wobbling in
Virginia and push a cold front south across the area through
early Sunday. A decent coverage of showers and thunderstorms can
be expected with this system overnight Saturday into early
Sunday morning. The low will open up and move off to the
northeast midday Sunday as another system moves in from the
west. The surface front associated with this system will move
across Sunday night also accompanied by showers and
thunderstorms. There should be a lull or minimum in convection
during the day Sunday but didn`t completely remove pops as the
ECMWF still paints a little activity across the area. Lows
Sunday morning should be in the lower 70s and a couple of
degrees cooler Monday morning in the wake of the front. Highs
Sunday should be in the lower 90s.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 300 PM Friday...An upper low across southeastern Canada Mon
will dive SE across NY and New England Tue and then move offshore of
New England Wed. An upper trough will extend all the way down the
East Coast for much of the week. By Friday, a ridge of high pressure
aloft across the southwestern U.S. may just nudge into the Southeast
States, as the upper trough finally moves well offshore. This
will keep a prolonged period of NW flow across the Forecast Area
which sometimes can be problematic with more convection
developing than the models foresee. The brunt of the shortwave
energy is expected to pass by to our N, but a weak impulse aloft
is currently progged to move across our Forecast Area Wed. At
the surface on Mon, low pressure offshore of the Mid-Atlantic
will be moving away as a cold front sags south and into the FL
peninsula and Gulf of Mexico. A trough will move across the
Carolinas Tue night. High pressure will then begin to build
across the Southeast later Wed and be reinforced from the N Thu
and Fri.
In general, the magnitude of dry air and increasing subsidence does
support the trend of little to possibly no convection during this
forecast period. Given the time of year, we are certainly not
completely confident a dry week will materialize. However, we are
definitely leaning in that direction with the current forecast only
including a slight chance for showers and thunderstorms Wed.
Much lower dewpoints are expected during this period, mainly lower
to mid 60s. Highs will be in the 80s each day, so very typical for
the first week of June. Low temps will finally return to more normal
levels as well, mainly in the 60s and as cool as the lower to mid
60s.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
As of 00Z...Area of TSRA to the west will approach and could affect
FLO/LBT with showers between 02Z and 04Z. Have VCTS at FLO/LBT and
tempo SHRA to account for these storms. Confidence is low in
exactly how this will play out but loss of daytime heating will be
an inhibiting factor as the evening progresses.
Otherwise...expect VFR conditions through most of the TAF period
with W-SW winds of 5 to 10 KT, becoming more southerly at coastal
terminals AFT 18Z. There is potential for MVFR BR all terminals
in the 08Z to 12Z window especially FLO/LBT if affected by showers
in the next few hours.
Extended Outlook...Primarily VFR. Tempo MVFR/IFR possible in morning
fog/stratus 09z-13z, or briefly in isolated showers and TSTMS.
&&
.MARINE...
NEAR TERM /THROUGH SATURDAY/...
As of 900 PM Friday...Seabreeze winds are dying away, but
synoptic winds are increasing as a southwesterly low level jet
develops overhead. Winds out at Frying Pan Shoals are a 2-3 knots
stronger than previously forecast, but other buoys/piers/coastal
observations are very close to expectations. Sea heights have
not responded to the winds, but could build by half a foot over
the next 4-6 hours. Discussion from 645 PM follows...
Southwesterly winds have increased to a solid 15 knots with
nearby gusts reported as high as 19 knots at the Sunset Beach
CORMP buoy. These stronger wind speeds should remain with us
through about 2 AM before winds gradually veer westerly and
diminish in speed late. Seas currently around 3 feet could build
to 4 feet briefly near Cape Fear. -TRA
Discussion from 300 PM follows...
Southwest winds will run about 10 to 15 kts tonight into
Saturday. The gradient will tighten later Saturday between
approaching trough and cold front from the west and high
pressure to the east. This should push winds up to 15 to 20 kts.
The winds will be W to SW through tonight into Sat. Seas will
remain between 2 and 4 ft through much of the period with
highest seas in the outer waters in offshore flow.
SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 300 PM Friday...Southwest winds of 15-20 knots will be in place
initially and continue for much of the overnight hours Saturday. A
cold front will move across the waters early Sunday with a brief
period of northwest winds ensuing. The northerly flow quickly washes
out to sea breeze influences and a typical summertime flow Sunday
persisting through most of Sunday night. Yet another front may push
across the waters very late in the period. Significant seas will be
2-4 feet.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
As of 300 PM Friday...A northerly flow will dominate into Tue
morning followed by a more westerly to perhaps southwesterly wind
later Tue and Tue night ahead of a trough. The wind direction should
briefly return to NW Wed morning before backing to SW and becoming
somewhat variable. As high pressure begins to build more strongly
across the waters Wed night and Thu morning, the wind direction will
settle on NE. The strongest winds this period will be during the
first half of Mon, up to around 10 kt. For the remainder of the
period, wind speeds should be less than 10 kt. Seas will be 2 to 3
ft through Wed with some lingering 4 ft seas across the outer
northern waters possible Mon.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...
NEAR TERM...TRA/RGZ
SHORT TERM...SHK
LONG TERM...RJD
AVIATION...MRR
Area Forecast Discussion
National Weather Service Northern Indiana
723 PM EDT Fri Jun 1 2018
.SYNOPSIS...
Issued at 144 PM EDT Fri Jun 1 2018
Tonight, lows will drop into the upper 50s and low 60s. Cool and
dry conditions are expected Saturday, with highs in the 70s and
low 80s under partly to mostly sunny skies. Dangerous waves and
currents are expected on Lake Michigan, so beachgoers should stay
out of the water.
&&
.SHORT TERM...(This Evening through Saturday)
Issued at 217 PM EDT Fri Jun 1 2018
Isolated thunderstorms will sweep across the area along the
boundary layer frontal trof. Instability is pooling right along
the leading edge; however shear and lift are not phasing well and
maximize along the southwestern edge of the line. This line moves
through steadily during the evening, exiting the warning area by
00Z. HRRR has been handling the boundary and convection well and
followed closely for the updates to the going forecast. In the
wake of the trof...cooler and drier air will settle in overnight.
Do not anticipate much in the way of inland fog, however there is
a chance that the cooler pool airmass could favor stratus
development over Lake Michigan.
Temp/Humidity levels will be much lower during the day Saturday.
With the relatively weakened flow, could have some lake induced
boundaries form...but lacking moisture do not expect to see much
more than some afternoon cumulus fields form.
&&
.LONG TERM...(Saturday Night through Friday)
Issued at 217 PM EDT Fri Jun 1 2018
Another trof will sweep into the region late Saturday. While the
timing is still in question, it does not look to be passing
through at the optimal diurnal period. Return moisture will be
late to arrive and this will limit the initial convection to start
late Saturday and persist through mid-day Sunday. The longwave
pattern becomes progressive and will favor a relatively quiet
period of weather through the mid to late week. With the ridge
building back into the Central Plains...could see a few short
waves eject off the Rockies...but banking on the timing of these
in the models is foolhardy at this time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday Evening)
Issued at 720 PM EDT Fri Jun 1 2018
A few showers may impact the vicinity of KFWA but bulk of
convection has ended for the evening. Cool/moist NE flow will
bring potential for stratus later tonight. Fuel alternate
conditions possible...especially at KFWA...but confidence is still
low and held with high-end MVFR for now. VFR and dry conditions
anticipated tomorrow as strong ridge slides over the region.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Beach Hazards Statement through Saturday morning for INZ003.
MI...Beach Hazards Statement through Saturday morning for MIZ077.
OH...NONE.
LM...Small Craft Advisory until 5 AM EDT Saturday for LMZ043-046.
&&
$$
SYNOPSIS...MCD
SHORT TERM...Lewis
LONG TERM...Lewis
AVIATION...AGD
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Area Forecast Discussion
National Weather Service Nashville TN
834 PM CDT Fri Jun 1 2018
.UPDATE...
FOR EVENING DISCUSSION.
&&
.DISCUSSION...
Surface observations show plentiful low level moisture remains in
place this evening with dewpoints in the upper 60s to lower 70s.
However, 00Z OHX sounding indicates atmosphere has dried out
significantly above 850mb with our PWAT way down to 1.13 inches.
This has kept Middle Tennessee in a dry pocket between showers and
storms just to our south in northern Alabama and to our north in
central Kentucky. Area should remain mostly dry overnight, but
several models indicate a shower or storm could sneak southward
into the northern Plateau counties after midnight - so added a
slight chance pop there. Otherwise, main impact tonight will be
fog as all model guidance shows at least patchy fog across most
of the forecast area and several show dense fog over our far
western, southern, and eastern counties. Added patchy dense fog
in a semicircle from the Tennessee River to the Alabama border
then up the west side of the Plateau for tonight based on this
guidance.
Looking ahead to Saturday, models such as the HRRR indicate an
isolated shower or storm is possible in the late morning across
the Plateau, then everywhere in the afternoon before area dries
out in the evening. GFS, ECMWF and NAM are all consistent in
showing a cluster or broken line of severe storms forming in
southeast Missouri late tomorrow, with this activity making a run
southeastward into at least western Middle Tennessee after
midnight Saturday night. As with the activity last night, it`s
uncertain how strong/severe these storms will be as they move
across the area and likely gradually weaken, as MLCAPE is forecast
to be much lower than Thursday night at only around 1200 J/Kg,
and deep layer shear will also be lower at around 20-30 knots.
However, mid level lapse rates will be quite steep at nearly
8C/km and DCAPE will be near 1000 J/Kg with substantial dry air
aloft depicted on forecast soundings, so cannot rule out some
damaging winds and large hail mainly west of I-65.
&&
.AVIATION...
00Z TAF DISCUSSION.
Currently have VFR conditions at all terminals. This will
continue through ~06Z. Patchy fog will begin to develop shortly
thereafter at KCSV and around 08Z/09Z for KCKV, KBNA, and KMQY.
Periods of IFR conditions will be possible at all terminals
through 14Z and maybe even LIFR conditions at KMQY and KCSV. VFR
conditions begin to return shortly after sunrise and look to stay
there for the remainder of the period. Winds will be at or below
5 knots throughout the period as well.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
DISCUSSION......Shamburger
AVIATION........MacDonald
Area Forecast Discussion
National Weather Service Paducah KY
627 PM CDT Fri Jun 1 2018
.UPDATE...
Issued at 625 PM CDT Fri Jun 1 2018
Update for 00z aviation only.
&&
.SHORT TERM...(Tonight through Sunday night)
Issued at 355 PM CDT Fri Jun 1 2018
More significant weather will be in the short time period for the
WFO PAH forecast area.
Beginning with late this afternoon, northern sections of the WFO
PAH forecast area (mainly the I-64 corridor in southern Illinois)
have been in a transition zone with respect to instability. There
has been a general cap over surface based instability (between
2500-2900 j2/kg2) with divergent flow, limiting any meaningful
theta-e convergence. However, since 19z the general low level flow
has shifted from south to north across southern Illinois, with
converging flow near KMVN (Mount Vernon, IL). With the approach of
a south-southwest to north-northeast oriented (positive tilt)
shortwave southward through Indiana/Illinois, anticipate that low
to mid- level lapse rates will sharpen and allow for
thunderstorms to develop south- southwestward into the I-64
corridor in southern Illinois, then gradually drift/propagate
southeast into southwest Indiana.
During the late afternoon, these storms may develop updrafts
strong enough to produce some strong wind gusts. At this time,
only have a mention of gusts to 40 mph in the hazardous weather
outlook, but may need to amend, should updraft/downdraft shear
increase enough to tap into stronger winds aloft, aiding downward
momentum. Hail potential may be limited with these storms as they
move into lesser favorable air.
A secondary area of concern has been a roughly west to east
convergence zone and instability gradient running along Crawleys
ridge/Shawnee Hills in southern Illinois and West Kentucky, arcing
up to Owensboro KY, where a weak surface theta-e convergence zone
has been setting up the past 2-3 hours. In addition, gravity waves
and cold pool from convection in Tennessee have moved northward
into west Kentucky. This feature will also serve to generate
isolated convection (which should die off with peak heating) late
this afternoon from the Crawley`s ridge area northeast to
Owensboro KY. Convergence overall will be more limited to create
pools of moisture convergence and instability.
The bigger question will be the timing and extent of the next
system on Saturday/Saturday night, which is currently
intensifying over North Dakota. The high resolution RAP guidance shows
significant ridging in place between this system and east seaboard
low/trough through early Saturday morning. The ridge does not
start to dampen until late afternoon (21z Saturday per RAP/CMC
guidance) keeping the warm sector boundary recurved further west
into southeast Missouri by late afternoon. The bodily transition
of the warm sector and attendant cold front will not likely shift
further east into the WFO PAH forecast area until the low level
jet kicks in toward sunset in response to a very narrow
(mesoscale) SSW-NNE orient shortwave extending across southeast
Missouri.
Anticipate the greatest severe threat will likely be in the
evening and early overnight (mainly between 7pm-2am) associated
with the passage of the front/upper trough. After 2am CDT, the
upper forcing and instability becomes more disrupted and severe
potential may become more scattered with time.
Given the upright and concentrated nature of this front, damaging
wind potential may peak out in the middle of Saturday evening
before diminishing toward midnight. Given the depth of convective
updrafts, hail will also be a consideration.
.LONG TERM...(Monday through Friday)
Issued at 355 PM CDT Fri Jun 1 2018
Following the passage of the trough and upper low to the east
Saturday night, broad scale synoptic scale ridging will dominate
the region from Sunday through early Wednesday. This will maintain
dry and gradually warmer weather across the region through this
time period.
Some of the medium range guidance takes a series of weak ripples
of small scale shortwaves embedded in the eastern Pacific U.S.
trough and gradually translate them over the ridge toward the WFO
PAH forecast area. This disturbed flow suggests a small chances
for rain may be possible from Wednesday night through Friday. At
this time, forecast confidence is somewhat low on timing and
location. For now, these chances for rain are within collaboration
limits with surrounding NWS office CWA`s.
&&
.AVIATION...
Issued at 625 PM CDT Fri Jun 1 2018
Not much to change in the TAF`s. Convection should be out of the
EVV and OWB areas by the top of the hour. With VFR conditions
prevailing after sunrise Saturday. Maintained and added fog for
the overnight hours. Also there will be some convection Saturday
into Saturday night but chance is too low to include at this time.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...KH
SHORT TERM...Smith
LONG TERM...Smith
AVIATION...KH
Area Forecast Discussion
National Weather Service Shreveport LA
858 PM CDT Fri Jun 1 2018
.UPDATE...
Continue to track convection across portions of Central Arkansas
this evening along old outflow boundaries from earlier convection.
There has been a trend over the last couple hours for this
activity to build further north and west as the convection moves
southeast which would suggest some of this could possibly make it
into portions of Union County, Arkansas later this evening but
latest 00z NAM is in good agreement with the latest HRRR in
suggesting that this activity should dissipate before it would
have a chance to affect our northeast zones.
Otherwise, hourly temperatures are running very close to those
experienced last night at this time and this would suggest similar
overnight lows tonight with what we saw last night. The current
forecast has a good handle on this. Did tweak hourly sky grids
slightly but this will not require an evening update tonight.
13
&&
.PREV DISCUSSION... /issued 531 PM CDT Fri Jun 1 2018/
AVIATION...
VFR conditions will prevail through the evening and a majority of
the overnight hours. Look for MVFR/IFR ceilings to return towards
dawn at most terminal locations, more confident on our NE TX
terminal locations seeing these conditions with the possibility of
IFR/LIFR vsby concerns at the LFK terminal as well between 10-13z.
IFR/MVFR ceilings should scatter out by 15-16z on Saturday with
VFR conditions returning. Light south winds overnight will become
SSW near 10 mph on Saturday.
Convection associated with a cold front Saturday Evening, into the
overnight hours appears to occur just beyond this TAF period and
will be addressed with the 06z TAF package.
13
PREV DISCUSSION... /issued 355 PM CDT Fri Jun 1 2018/
SHORT TERM.../Tonight through Saturday Night/
Hot and humid conditions prevail across the region. An approaching
cool front may act to pool additional moisture with daytime
dewpoints remaining above 70 degrees. However, gfs model is mixing
out dewpoints despite this, which may in part be due to a possible
lesser amount of low mrng clouds. Also, cumulus development may
by significant by mid aftn, leading to temps topping out in the
early to mid aftn and resulting in a narrow window for heat
indices approaching the 105 criteria. Also, much less humid
conditions for Sunday. Thus, despite concerns for these hot temps
on a wknd, have opted not to issue heat advisory for Saturday.
Expect a fairly narrow zone of stg instability with front entering
nw cwa late aftn/early eve Sat, and working its way swd Sat eve
and night. PW values may exceed two inches with locally heavy rain
and gusty winds possible in storms prior to sunset.
/07/
LONG TERM.../Sunday through Friday/
During the day Sunday, a cold front, associated with an upper level
trough of low pressure rounding the Northeast periphery of an upper
level ridge of high pressure over Mexico and across the Rockies,
will be spreading Southeast out of the Four State Region. Surface
high pressure will be building into the forecast area with only small
chances for showers and thunderstorms over the far South zones.
Daytime high temperatures will only climb into the upper 80s to the
middle 90s. The overnight low temperatures Sunday night into early
Monday morning will also be cooler with readings ranging from the
lower 60s to around 70. Dry conditions are expected to carry over
into late Monday when a short wave trough of low pressure will be
moving through the upper level ridge across while the Western end of
the earlier cold front that will become stationary will pivot and
return as a warm front. The upper disturbance and the frontal
boundary will be the focus for showers and thunderstorms for Monday
night into Tuesday across the West and North sections of the area
and over the East for late Tuesday into Wednesday. For the later
part of the work week the upper ridge of high pressure will be
amplifying into the Central sections of the country. Temperatures
will be warming for the later half of the work week during the
daytime and overnight under the influence of the ridge with very
slight chances of any showers or thunderstorms into the weekend.
/06/
PREV DISCUSSION... /issued 1252 PM CDT Fri Jun 1 2018/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 76 96 73 93 / 0 10 30 10
MLU 75 95 74 91 / 0 10 30 10
DEQ 74 94 68 91 / 10 20 30 0
TXK 75 95 72 91 / 0 10 30 10
ELD 74 95 71 90 / 0 10 30 10
TYR 75 95 73 92 / 0 10 30 10
GGG 76 96 73 93 / 0 10 30 10
LFK 76 95 74 94 / 0 10 20 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
13/13/07/06
...Update to aviation forecast discussion...
.SHORT TERM...(This evening through Saturday)
Issued at 329 PM CDT Fri Jun 1 2018
Early this afternoon an upper level trough was lifting northeast
across the central Rockies. A southern stream ridge axis extended
from central Mexico, northeast across central TX and across eastern
KS into western IA. As the upper level trough lifts northeast into
the norther high plains, height falls and DCVA will provide strong
ascent along with surface convergence along a pacific cold front for
numerous thunderstorms to develop across west central and north
central NE late this afternoon and into the early evening hours.
These initial storms across central NE may be scattered to discrete
supercells but as the ascent increases ahead of the approaching H5
trough, numerous severe thunderstorms will develop with coalescing
cold pools to form a forward propagating MCS. Through the evening
hours a south-southwesterly low-level jet will increase to 40-45 KTS
across eastern KS and and eastern NE. The forward propagating MCS
should propagate along the deeper moisture and instability axis
across northeast KS. Most CAM solutions have the MCS moving
southeast into the northern counties of the CWA late this evening to
around 6Z SAT. The HRRR models continues to be the slowest
developing the forward propagating MCS and slowly moving the MCS
southeast into the north central counties of the CWA by 9Z, then
southeast across southeast and east central KS from 9Z through 12Z
SAT. The NMM version of the WRF and the 3KM NAM continued to be the
quickest solutions in developing a broad MCS across south central NE
by 2Z SAT, which propagates southeast across much of the northern
counties by 6Z SAT, then across the remainder of the CWA through 9Z
SAT. In the weather grids I split the difference between the CAM
solutions. The MCS across west central and central NE will probably
develop by 3Z then move into the northern counties of the CWA by 6Z.
The HRRR and ARW WRF, show the most intense portion of the forward
propagating MCS tracking east of a Washington, to Emporia line.
Given the stronger low-level jet any organized forward propagating
MCS will produced severe wind gusts even if a shallow inversion
develops during the mid and late evening hours. The 0-6KM effective
shear will be will be sufficient to produce new intense updrafts
along the cold pool generated outflow boundary. I don`t see the
outflow outrunning the convective complex, so there will be the
threat of damaging wind gusts across much of the CWA, especially
across the northern and eastern counties of the CWA. The evening
shift should have a better track and timing on this MCS, once the
MCS begins to develop across south central NE this evening.
Once again, the primary hazard will be damaging wind gusts with the
forward propagating MCS. However, several of the numerical models
are forecasting 0-1KM SRH of 300-500 J/KG developing ahead of the
MCS during the late afternoon and early morning hours. Given the
strong low-level vertical windshear, individual updrafts that
develop along the OFB may enhance the local RIJ that could tilt any
horizontal vorticity generated along the the OFB and and ingest this
horizontal vorticity into the updraft, in a stream-wise fashion,
which could produce meso-vortices. These mesovorticies will
intensify the individual updrafts resulting in the potential for
some isolated larger hail and brief meso-vortices tornadoes. Heavy
rainfall, especially along the leading edge of the MCS may cause
isolated flash flooding. The MCS should move fairly fast, thus I
don`t expect a prolong period of heavy rainfall.
Saturday, the MCS should weaken as it moves southeast of the CWA
during the mid morning hours. There could be some lingering
stratiform rainshowers through the mid morning hours across the
eastern counties of the CWA. Skies will clear as the H5 trough shift
east into the upper Midwest during the afternoon hours of Saturday.
Low-level CAA behind a surface cold front will advect a cooler and
drier airmass southeast across the CWA. Highs on Saturday will only
reach the lower to mid 80s with a refreshing northwest wind at 15 to
20 MPH.
.LONG TERM...(Saturday night through Friday)
Issued at 329 PM CDT Fri Jun 1 2018
Sunday, a southern stream ridge will shift east across the central
plains, light easterly surface winds will prevent highs from
reaching the 90s, so we may have another day with highs in the mid
to upper 80s.
Monday, a weak southern stream upper trough will move east across
KS. There may be enough ascent ahead of the H5 trough combined with
deeper moisture return for afternoon showers and thunderstorms to
develop. Highs on Monday will reach the mid to upper 80s.
Tuesday through Friday, an upper level ridge axis will amplify
across the plains through the end of the week. Expect mostly dry
conditions with a warming trend. Highs will reach the mid to upper
90s through the end of the workweek.
&&
.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 639 PM CDT Fri Jun 1 2018
Not much impactful change to the previous forecast. Delayed TS
chances a bit but still much uncertainty on specific timing and
coverage to convection. LLWS should develop around 06Z while
northwest surface winds take hold around 15Z behind the cold
front.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Gargan
AVIATION...65
Area Forecast Discussion
National Weather Service Tulsa OK
910 PM CDT Fri Jun 1 2018
...UPDATE...
.DISCUSSION...
This evening a surface low was located across the Northern Plains
with a trailing cold front extending southwest into Colorado.
From the cold front a dryline was positioned from Eastern Colorado
through the Oklahoma Texas Panhandles and into Southwest Texas.
Scattered convection had developed along the dryline in West
Texas while at the same time an MCS was developing across
Nebraska. To the south and east of these features...across Eastern
Oklahoma and Northwest Arkansas...mostly clear skies with temps
in the 80s were common.
Overnight tonight...the convection in Texas is expected to remain
in Texas...though scattered associated cloud cover looks to move
across Southeast Oklahoma. Also...the developing MCS is forecast
to dive southeast overnight into Western Missouri as the cold
front continues to push southeast toward the CWA. This will help
to also increase cloud cover across Northeast Oklahoma into
Northwest Arkansas tonight. Latest HRRR model run tries to bring
the southern part of the MCS close to the CWA around 12z Saturday.
For now will continue with pops below mentionable criteria for
tonight and let ride the slight chance pops for after 12z.
Scattered cloud cover...southerly winds 5-15 mph and dewpoints
remaining in the 70s ahead of the approaching cold front will aid
in low temperatures tonight close to this mornings lows of upper
60s to upper 70s forecast. For the evening update...have only
added minor tweaks to hourly temp/dewpoint/sky/wind grids to
account for latest trends and observations. The rest of the
forecast seems to be in good shape at this time.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 79 92 62 87 / 0 20 10 0
FSM 76 95 65 88 / 0 30 20 0
MLC 77 94 65 87 / 0 20 10 0
BVO 74 90 55 86 / 10 20 10 0
FYV 71 88 56 82 / 0 40 10 0
BYV 73 89 61 82 / 0 40 20 0
MKO 76 92 62 86 / 0 20 10 0
MIO 75 89 61 84 / 10 20 10 0
F10 77 92 64 86 / 0 20 10 0
HHW 76 95 68 89 / 0 30 30 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...None.
AR...None.
&&
$$
SHORT TERM...20
AVIATION.....10