Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 07/07/17
Area Forecast Discussion
National Weather Service Albuquerque NM
535 PM MDT Thu Jul 6 2017
.AVIATION...
00Z TAF CYCLE
Showers and thunderstorms through this evening over the northwest
third of the state. FMN and GUP are most likely to be impacted and
will carry a 2 hour TEMPO group at these sites. With weak showers
around ABQ and AEG will carry a -shra at these sites as well til
02Z. Pretty much the same scenario for Friday. All TAF sites should
be VFR through Friday although brief MVFR and MT obscurations is
possible in a stronger shower.
&&
.PREV DISCUSSION...327 PM MDT Thu Jul 6 2017...
.SYNOPSIS...
Strong high pressure aloft near the Four Corners will continue to
strengthen as it shifts a little farther west over Utah through the
weekend. This position will maintain a broad northeast to southwest
steering flow aloft over the area that will favor isolated to
scattered thunderstorms over the high terrain and western half of the
state. The upper high will gradually weaken and drift back toward
east early next week with indications that the high will center over
the southern plains states by Tuesday. This will allow for gradual
increase in storm coverage early next week.
&&
.DISCUSSION...
Isolated to scattered thunderstorms of the drier variety and associated
localized downburst wind threat will remain the focus through this evening
for roughly the northwest half of the state. Very dry/broadly subsident
mid-level air stream evident across the southeast half where even
towering cumulus vicinity of the higher terrain have been struggling.
Recent Rapid Refresh runs have consistently shown at least isolated
convection over the central and south-central mountain ranges mid to
late afternoon slowly rolling toward the southwest into the
middle/lower RGV by early evening. The 3km NAM CONUS is much less
aggressive. A more likely scenario would be isolated virga bombs (no
CG strikes) which is still a significant concern but not as robust
as what the HRRR predicts. Another significant concern... outflow
winds from convection drifting toward the southwest could become
problematic for portions of central NM to include the ABQ Metro. Will
include a mention of light showers or sprinkles lingering after
midnight for parts of NW/WC zones. Otherwise, another quiet overnight
period expected.
Strong high pressure aloft vicinity of the Four Corners will continue
to strengthen as it repositions a little farther north/west over
Utah through Friday. The upper high will remain anchored over the
southern Great Basin this weekend with 500mb heights gradually
lowering a few decameters between Friday and Sunday. There may be a
weak boundary flirt with the northeast late Friday or Saturday but
more importantly the steering flow would be a little more favorable
to bring convection over SC Colorado into that part of the area.
Growing confidence that the upper high will gradually shift/reposition
farther east early next week. Models generally support a broad
anticyclonic belt extending from the Colorado Rockies to the southern
plains with the ridge axis over far northern NM or just north of the
state. Resultant east or southeasterly flow beneath the high would
open the door for a westward-moving wave or two and support a nice
moistening trend beginning Sunday with PWAT near once inch at ABQ. KJ
&&
.FIRE WEATHER...
Not many changes made to the gridded forecast. Just a few near term
subtle changes in terms of delineating drier storms/LAL 6 as well as
some added overnight convection. Models haven`t really changed their
tune all that much in terms of the overall weather pattern next
several days. Humidity values will incrementally rise...albeit small
through the weekend. Upper high will be situated over the greater
Four Corners area. Broad ENE steering flow for the storms. The
footprint of wetting rain coverage will increase ever so slightly
through the weekend. Western and central areas will be
favored...especially mountainous areas. Lightning ignition
probabilities will remain on the higher side. Similarly...strong
outflow and downdrafts will be associated with the
storms...especially mid afternoon through mid evening.
As far as the weather trend for next week...persistence will be a
pretty good forecast. Models are showing an eastward extent or
movement to the upper high as the week progresses. Storm coverage
however, should remain over western and central areas. Eastern areas
will have to contend with a mid level dry intrusion and capping
characteristics associated with the high. Humidity values look to be
near normal for the period and not showing signs of a significant
wet phase Monsoon burst. More of the normal smaller scale wetting
rain shaft thunderstorms. High temps should be near to a little
above normal.
Will need to watch for a more significant back door cold front the
following weekend which would help boost wetting thunderstorm
coverage and potential. 50
&&
.AVIATION...
18Z TAF CYCLE
50
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion
National Weather Service Albany NY
924 PM EDT Thu Jul 6 2017
.SYNOPSIS...
A wave of low pressure moving up the eastern seaboard
will allow for some rain showers for far southern areas for tonight
into tomorrow morning. With a more humid air mass in place, some
additional showers and thunderstorms will be possible for the entire
area for tomorrow afternoon and evening, especially for areas to the
west of the Capital Region. Some more showers and thunderstorms
will accompany a frontal passage on Saturday, before drier and less
humid air works its way into the area for Sunday.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
As of 920 PM EDT...Plenty of mid and high level moisture is
moving northeast towards the area, allowing for lots of cloud
cover this evening.
Through the evening hours, most areas look to stay dry thanks to
the lack of large-scale forcing. Low-level moisture has been
increasing, which has been allowing dewpoints to creep back up
into the 60s for many locations.
As the upper level disturbance continues to slide eastward
towards the mid-Atlantic, it will allow a weak surface wave of
low pressure to develop and start to head northeast up the east
coast for late tonight. The 3km HRRR and NAM suggest that some
locally heavy showers may accompany the track of the surface
low, although the models tend to agree that this should remain
far enough south/east of our region. Still, cannot totally rule
out some these heavier showers brushing into parts of the mid-
Hudson Valley and NW CT, so will allow for a period of showers
there for late tonight.
Elsewhere, it looks to stay dry for most of the night. Cannot
totally rule out a stray shower further north, but best chance
for seeing rain looks to be closer to the coastal wave.
Otherwise, it should remain mostly cloudy across the area, with
temps only falling into the 60s for most spots.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
During the day on Friday, the coastal wave should be heading
towards eastern New England by later in the day. Best chance of
rain for our southeastern zones will be for the morning hours,
and any rainfall could be locally heavy thanks to PWATS rising
to near 2.00 inches for far southeastern areas. Otherwise, the
day will be starting off mostly cloudy everywhere. However, some
breaks of sun should occur by midday or early afternoon, as the
coastal wave starts to move away from the area and our area
remains upstream of an approaching upper level shortwave
heading from the Great Lakes.
With the breaks of sun, some surface-based instability occur, with
up to 1000 J/kg possible for western areas. Best chance will be
for areas far west of the Capital Region, as enough clouds may
linger in eastern areas to keep instability limited for those
areas. 0-6 km bulk shear will be increasing as the shortwave
approaches, with values of 30-40 kts by late in the day. With
breaks of sunshine, highs in valley areas should reach into the
upper 70s to low 80s.
The 3km NAM shows a broken line of showers and embedded
thunderstorms approaching by the early evening hours from
western and central New York. Although instability will be
decreasing in the evening thanks to the loss of daytime heating,
there could be an isolated strong to severe storm along with
line for western areas by late in the day. SPC has areas west of
the Hudson Valley in a Marginal Risk for severe t-storms and
will continue to mention this in the HWO as well.
Further east, the threat will be lower, as the line should be
weakening after dark as it heads east towards western New
England. Still may be some showers or embedded rumbles
overnight, but the threat for severe storms should be done. It
will continue to be warm and muggy overnight with lows in the
60s.
The cold front will be crossing during the day on Saturday from
west to east. Models show some surface-based instability so will
continue to mention a slight chance to chance for thunder, along
with some rain showers, as the front passes through the area.
Best chance looks to be morning through early afternoon, as the
front should be crossing through by then, and some clearing will
start to occur. Highs should be low 70s to mid 80s across the
area, with the warmest temps in southeastern areas, where the
front will be last to cross.
Cooler and less humid air will be moving in for Saturday night.
It should be dry, with decreasing amounts of cloud cover through
the night. Lows look to fall into the 50s.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
Dry weather is expected at the start of the long term forecast
period with unsettled weather expected by the early to middle part
of next week.
Sunday through Sunday night is expected to be mainly dry as a large
ridge of high pressure becomes anchored across the eastern seaboard.
There could be a few showers across the northwest corner of the
forecast area. Highs on Sunday are expected to be in the upper 60s
to mid 80s with lows Sunday night in the 50s.
Unsettled weather is expected Monday through Tuesday night as a
couple of frontal boundaries move through the region. Highs Monday
and Tuesday are expected to be in the upper 60s to mid 80s. with
lows Monday night and Tuesday night in the mid 50s to mid 60s.
Tuesday looks like the wettest day of the long term period with
scattered thunderstorms expected in addition to showers.
Wednesday and Thursday look mainly dry although there could be a few
showers across eastern area Wednesday night and across northwest
areas on Thursday. High pressure will be moving across northern New
York and northern New England through the period. Highs on Wednesday
and Thursday will be in the upper 60s to lower 80s with lows
Wednesday night in the 50s to lower 60s.
Overall expect temperatures and precipitation to average near normal
during the long term period.
&&
.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
Stronger upper energy to our south will push north and east
through the night and Friday morning spreading more widespread
rain toward the KPOU and KPSF areas after midnight tonight.
So, VFR conditions with scattered to broken clouds above 3000 feet
through this evening until the stronger upper energy approaches and
low level moisture increases through the night. Ceilings and
visibilities are expected to fall into the MVFR range at KALB and
KGFL after the threat of of showers end between 09Z-14Z. The rain
at KPOU and KPSF after 07Z-10Z will result in ceilings and
visibilities dropping into the MVFR range. Steadier rain after
about 12Z-13Z will make ceilings and visibilities deteriorate toward
the borderline MVFR/IFR range. Late in the day another round of
showers and scattered thunderstorms will approach from the
north and west. Have indicated PROB30 at the TAF sites for much
of the afternoon hours
Winds will become light south at below 6 Kt after sunset. South
winds increase again to 5 to 10 Kt Friday morning.
Outlook...
Friday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Saturday: Moderate Operational Impact. Chance of SHRA...TSRA.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: No Operational Impact. NO SIG WX.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: Low Operational Impact. Slight Chance of SHRA.
Monday Night: Moderate Operational Impact. Chance of SHRA.
Tuesday: High Operational Impact. Likely SHRA...TSRA.
&&
.FIRE WEATHER...
Low pressure will move up the Northeast coast for late tonight
into tomorrow morning, with some rain showers for far
southeastern areas. The entire region will see a chance for some
showers or thunderstorms later tomorrow through Saturday. Some
areas will see a wetting rainfall during this time.
RH values will only fall to 50 to 70 percent tomorrow with south
winds of 5 to 10 mph. RH values will continue to be similar on
Saturday, with south-southwest winds becoming west at 5 to 15
mph.
&&
.HYDROLOGY...
Widespread hydrological issues are not expected the next several
days on the main stem rivers.
A wave of low pressure will move up the eastern seaboard tonight
into tomorrow morning. Although the bulk of the rainfall may
avoid our area to the south and east, there could be a brief
period of some steadier rain showers for the mid-Hudson Valley
into northwestern Connecticut. Although it will ultimately
depend on exactly where showers and isolated t-storms track, up
to an inch of rain is possible for far southeastern areas
through late tomorrow morning. This rainfall could cause some
ponding of water on streets and other poor drainage areas, but
no flooding is expected.
Some additional showers and thunderstorms are possible for the
whole area between tomorrow afternoon and Saturday evening as a
frontal system impacts the area. Rainfall amounts will be
variable, but widespread flooding/flash flooding is not expected
with this storm system. As always this time of year, any
thunderstorm is capable of locally heavy downpours.
Drier weather will return for Sunday into Monday, but the
threat for showers and thunderstorms will return with another
storm system on Tuesday.
For details on specific area rivers and lakes, including observed
and forecast river stages and lake elevations, please visit the
Advanced Hydrologic Prediction Service /AHPS/ graphs on our
website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...Frugis
NEAR TERM...Frugis/11
SHORT TERM...Frugis
LONG TERM...11
AVIATION...11/NAS
FIRE WEATHER...Frugis
HYDROLOGY...Frugis
Area Forecast Discussion
National Weather Service Gaylord MI
1016 PM EDT Thu Jul 6 2017
.UPDATE...
Issued at 1016 PM EDT Thu Jul 6 2017
Round two of organized strong-severe storms is currently moving
through the SE section of the CWA...round three is moving out of
central upper into Green Bay out ahead of approaching cold front
which is back in western upper Michigan. Still plenty of conditional
instability out there per SPC mesoanalysis page...although
boundary layer has certainly cooled/stabilized a bit which should
lessen our severe weather threat over the next several hours.
Will just have to see just how well this next round of convection
survives the trip across the lake and/or how well it can flare
back up upon reaching lower Michigan.
Otherwise...upstream cold front will work through the region
during the overnight hours...largely bringing an end to the precip
threat and ushering in noticeably cooler weather for Friday.
&&
.NEAR TERM...(Tonight through Friday)
Issued at 251 PM EDT Thu Jul 6 2017
...Severe thunderstorms possible into this evening...
High impact weather potential...Large hail and gusty winds possible
in stronger thunderstorm activity this afternoon and evening.
Pattern synopsis/forecast...Shortwave trough digging southeast out
of southern Canada, with an increasingly defined cold front racing
out just ahead of it. Northern Michigan clearly within the warm
sector this afternoon, as evident by temperatures up into the 70s
and 80s and dewpoints well into the 60s. Sharp instability gradient
lies within this warm/moist sector, with upwards of a few thousand
joules/kg of most unstable cape across sections of our area per
latest RAP analysis. Earlier MCS is long gone, but associated
outflow boundaries and convectively agitated mid levels has resulted
in renewed shower and thunderstorm development this afternoon, which
is punching east across the area as of this writing. Storms have
largely behaved, although radar trends definitely suggest some small
hailers and isolated gusty winds. Further west, the destabilization
process has begun as earlier cloudy skies have cleared. Approach of
cold front and remnant outflow/differential heating boundaries may
yet be the trigger for additional storms to develop within this
developing instability axis.
Cold front gets a kick southeast overnight as mid level flow
consolidates and strengthens, clearing our area near or shortly
after sunrise.
Primary forecast concerns/challenges...Addressing severe weather
potential into this evening.
Details...Low confidence forecast indeed heading through the
remainder of this afternoon and evening. Cold pool triggered showers
and thunderstorms will continue to propagate east across the area
the next few hours, waiting on additional upstream development to
arrive later this afternoon and evening as main cold front nears.
Much uncertainty on just how organized this upstream convection will
become, although earlier mentioned destabilization and arrival of
primary wave/cold front does support some decent organization. Would
tend to believe best activity would translate southeast as ongoing
overhead convection begins to stabilize the environment. While not
overly strong, deep layer and effective shear in excess of 35 knots
and still robust instability outside outflow stabilization area may
yet result in some severe weather later this afternoon through early
evening. Not a slam-dunk by no means, but something to monitor for
sure. Front clears the region from northwest to southeast overnight,
ending the rain threat in the process.
Despite frontal passage, lingering low level moisture and enhanced
surface convergence within background northwest wind environment may
provide a few afternoon showers across portions of northeast lower
Michigan Friday. Shouldn`t be a big deal, with much of the area and
most of the time remaining dry. It will be noticeably cooler and
drier on Friday.
&&
.SHORT TERM...(Friday night through Sunday)
Issued at 251 PM EDT Thu Jul 6 2017
...Dry through Saturday; rain chances Saturday night into Sunday...
High Impact Weather Potential...None.
Pattern Synopsis/Forecast...Upper level trough axis will pivot
across the Upper Great Lakes Friday night with cold air advection
ongoing. Longwave trough pattern will remain over the region through
the weekend as a deep cutoff low wobbles over Hudson Bay. However,
surface high pressure over the central/northern Mississippi Valley
combined with a dry airmass overhead is expected to keep dry
conditions over the area through Saturday. A cold front will drop
south across northern Michigan late Saturday night into Sunday,
interacting with a narrow ribbon of higher PWATs ~1 inch along the
front. This will bring the next chance of showers...and possibly a
few storms by Sunday afternoon with increasing daytime instability.
Temperatures look to remain a tad below normal.
Primary Forecast Concerns...Rain chances Saturday night into Sunday
will be the main forecast concern. Fgen lift looks to be strongest
along the front as it crosses through eastern Upper, gradually
weakening as it progresses further south through the day Sunday.
Meanwhile the better instability and hence thunder potential looks
to develop generally south of M-72 Sunday afternoon. Not expecting
severe storms.
.LONG TERM...(Sunday night through Thursday)
Issued at 251 PM EDT Thu Jul 6 2017
An early week cold front and shortwave will bring the primary
chances for rain, and possibly some thunder, as high pressure will
be overhead for the remainder of the week. Pattern remains blocky,
and a cutoff low over the Gulf of Alaska could eject some shortwaves
and kick off showers in currently expected dry periods. Temperatures
will warm through the period, starting near normal and warming to
slightly above by Thursday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 805 PM EDT Thu Jul 6 2017
Batch of thunderstorms continue over parts of NE lower Michigan
this hour...close to APN. But otherwise TSTM threat at the
terminal sites is minimal for the the next few hours. There is a
batch of TSTMs moving through far western upper Michigan that will
roll down through northern lower Michigan late this evening into
the overnight hours...but should weaken before getting into the
area. Will see...
Cold front swings through the region overnight into Friday
morning. Behind the front...there may be a period of MVFR and
possible IFR cigs Friday morning as the shallow cooler airmass
overspreads the region. Improvement for the afternoon.
Outside of any storms...winds will be generally under 10
knots...westerly tonight turning into the north for Friday.
&&
.MARINE...
Issued at 251 PM EDT Thu Jul 6 2017
Southwest to west winds become northwest overnight and
Friday as a cold front crosses the region. Thunderstorms remain
possible prior to this frontal passage, some of which could become
strong to severe producing very gusty winds and large hail.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...TBA
NEAR TERM...MSB
SHORT TERM...MEK
LONG TERM...MEK
AVIATION...TBA
MARINE...MSB
Area Forecast Discussion
National Weather Service Quad Cities IA IL
951 PM CDT Thu Jul 6 2017
.UPDATE...
Issued at 938 PM CDT Thu Jul 6 2017
Monitoring convective trends over WI for any updates to going
forecast. Appears best chance for storms would be in our
N IL counties late eve into overnight per 1) favorable E/SE
propagation vectors and/or 2) additional development aided
by outflow boundaries, and impinging 850 mb moisture transport
and convergence. SPC has downgraded to marginal risk given
uncertainties in convective trends and magnitude (given later
timing). Still though any stronger storms should pose a risk of
large hail given WBZ height ~9800 ft AGL per DVN 00z RAOB combined
with steep mid level lapse rates of nearly 7c/km 850-500 mb and
dry air aloft along with bulk shear 0-6km of 40+ kts. Strong,
gusty winds also possible with sub-cloud dry air, very steep sfc-
3km lapse rates of nearly 9c/km and DCAPE of 1000-1500 j/kg. Have
kept pops in lower chance for now and will keep an eye for any
changes. Otherwise, rest of the cwa precip prospects would appear
quite low, but non-zero given surface cold frontal passage.
However, would appear isolated coverage at best given presence of
EML near 800 mb, and latest NAM/RAP models depicting flow veering
and convergence washing out near to just above 850 mb in absence
of any coherent trigger aloft not readily noted with latest
observational data set.
&&
.SYNOPSIS...
Issued at 253 PM CDT Thu Jul 6 2017
18Z surface analysis has a cold front running from northeast
Minnesota into South Dakota. Dew points ahead of the front were
mainly in the 70s with 60s and cooler behind the front.
&&
.SHORT TERM...(This Evening through Friday)
ISSUED AT 253 PM CDT Thu Jul 6 2017
Although cumulus clouds have developed this afternoon, satellite
trends have not shown any additional development. These trends taken
in concert with RAP trends suggests the atmosphere is probably
capped in regards of convective storms developing. Thus although not
zero, it appears that dry but humid conditions will be seen through
sunset.
After sunset, the question then becomes where will the thunderstorm
complex that develops across WI/MN go. RAP trends indicate a
majority of the activity will remain north of the area but
boundaries put out by the storm complex will move into the area.
These boundaries may provide just enough forcing to initiate new
convection that will move through most of the area before sunrise
Friday.
How the storms develop and evolve on these boundaries will be
important. Given the energy that will have built up during the
daylight hours, one cannot rule out any severe storms. Based on what
is being suggested, wind would be the primary threat with hail a
secondary threat. Areas north of highway 30 would be favored for
any severe storms.
Friday, any lingering convection in the far east and southeast will
exit the area by the morning commute. Otherwise, expect dry and less
humid conditions across the area with temperatures close to normal.
.LONG TERM...(Friday Night through Thursday)
ISSUED AT 253 PM CDT Thu Jul 6 2017
Occasional active weather will dominate the long term forecast
period.
Friday night into early Saturday will be a continued reprieve from
the hot, humid, and stormy weather of late. Expect slightly below
normal temps, with lows Friday night in the upper 50s/low 60s and
highs Saturday mainly in the 80-85 degree range.
Saturday afternoon, a warm front is forecast to lift north into the
area and depending on the eventual location, could be the focus for
thunderstorms during the afternoon and night. The shear/instability
profiles indicate a low threat of significant severe weather.
Looking ahead to Sunday, a boundary will likely remain in the area,
but there is considerable model spread regarding the location and
the track of short wave energy in the northwest flow. The GFS has a
high CAPE/low shear scenario with pockets of heavy rain and isolated
downburst winds the main issues.
Next week, look for more hot and humid weather as upper ridging
builds into the midwest. Monday and Tuesday should be the most
active days with synoptic models suggesting several thunderstorm
complexes with attendant heavy rain/severe threats.
Additional scattered convection cannot be ruled out Wednesday into
Thursday, with low confidence in timing/coverage at this time.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday Evening)
ISSUED AT 636 PM CDT Thu Jul 6 2017
VFR conditions expected to dominate the TAF cycle. Chance of storms
exists late this evening and overnight, but EML and lack of forcing
makes for low confidence on occurrence and coverage, thus have left
out any mention in 00z TAFs. Most favored timeframe for any
development should it occur would be just ahead of cold front, as it
passes through the terminals between roughly 07z-13z. Friday will
bring gusty NW winds 10-20+ kts by mid morning through afternoon.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...McClure
SYNOPSIS...08
SHORT TERM...08
LONG TERM...RP Kinney
AVIATION...McClure
Area Forecast Discussion...UPDATED
National Weather Service Fort Worth TX
830 PM CDT Thu Jul 6 2017
.UPDATE...
Most of the showers and thunderstorms that developed this
afternoon have dissipated. The 18z NAM NEST indicated that
isolated showers/thunderstorms would form just south of the Red
River and move southeast early this evening, but am not seeing
this on satellite or radar. The HRRR and the 18z TTU WRF indicate
that we will be rain-free for the rest of tonight. Have lowered
the PoPs to less than 20 percent for now and if the 00z NAM NEST
comes into line, will do another update to remove mention of rain
at all for the rest of tonight. Have also made minor adjustments
to bump up the high temperatures by a degree or two across most of
the forecast area for Friday and Saturday. Updates have been sent.
58
&&
.AVIATION... /Issued 625 PM CDT Thu Jul 6 2017/
Isolated thunderstorms will continue into the early evening in
vicinity of DFW Metroplex TAF sites. Will carry VCTS through 01z
at which point convection should be on a downward trend with loss
of heating. Winds are generally light and variable with the
exception of locations impacted by thunderstorm outflow.
For the remainder of the TAF period, VFR conditions will prevail
at all sites. Light erratic winds will become predominantly
southeast on Friday, but remain around 5-8 kts. There is a chance
for an isolated diurnally-driven shower or storm to develop Friday
afternoon, but the potential is too low to include in any of the
TAFs at this time.
-Stalley
&&
.DISCUSSION... /Issued 302 PM CDT Thu Jul 6 2017/
Upper level trof continues to bisect the area this afternoon as
clearly evident on water vapor imagery. Drier air at mid and
upper levels is slowly sagging southward towards the I20/30
corridors with the highest moisture south of this area with
corresponding to PWs in the 1.8-2.0 inch range. Even in the drier
air...showers and thunderstorms have popped up early this
afternoon and we will continue to see additional thunderstorm
activity develop through the afternoon into the early evening with
highest pops and better chances for locally heavy rainfall south
of the I20/30 corridors. Overall coverage appears that it will be
less than yesterday...but where the higher moisture exists
rainfall rates and slow movement of storms may produce a brief
flash flooding threat.
Short-term models pretty consistent with showing much of the
convection dissipating rapidly shortly after the 00Z timeframe
though a few storms will be possible in the areas with the higher
moisture content across the southern zones.
Friday looks to be very similar to today though overall coverage
should be a bit less with the higher chance for pops over the
eastern and southern zones as the upper level trof continues to
slide slowly eastward and becomes more diffuse and this regime
will likely continue into the weekend as well.
By early next week...center of upper high that has been located
over the western U.S. shifts more towards the Southern Plains and
then expands into north Texas into the middle and latter portions
of next week. This should result in decreasing chance for pops and
increasing high temperatures. With moisture in ground from recent
rainfall...temps should be held down a bit from what they would be
otherwise for this time of year. On the other hand....humidity
levels will continue to be high making for afternoon heat values
in the 105-110 range.
Wiley
&&
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 76 96 77 96 76 / 10 10 5 10 5
Waco 76 96 75 97 75 / 10 30 10 20 20
Paris 72 95 74 91 73 / 10 10 5 30 20
Denton 74 95 75 94 75 / 10 10 5 10 5
McKinney 74 94 74 93 75 / 10 10 5 10 10
Dallas 77 96 77 96 76 / 10 20 5 10 5
Terrell 73 93 74 94 75 / 10 20 5 20 10
Corsicana 75 94 75 94 75 / 10 30 10 20 20
Temple 74 96 74 97 74 / 10 30 10 30 20
Mineral Wells 72 94 73 95 73 / 10 20 5 5 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
58/26
Area Forecast Discussion
National Weather Service Hastings NE
701 PM CDT Thu Jul 6 2017
.SHORT TERM...(This evening through Friday)
Issued at 223 PM CDT Thu Jul 6 2017
Forecast concerns include small chances for tstms in the next 24 hrs
along with extent of cooling for Friday.
Current water vapor imagery along with 12Z upper air analysis shows
a high amplitude ridge over the western half of the country with the
high centered near the four corners region. Looks to be broad
troughing in the east with the low/trough that has lingered to our
southeast the past several days now phasing in with the northern
trough. This puts our area in N to NW mid/upper flow as evidenced by
MCS overnight that dove south and affected our northern CWA before
weakening. 15Z surface analysis had low pressure extending from NW
Minnesota to the SW part of the Neb panhandle. Decent pressure rises
of 2 mb per 3 hr behind the trough/front should help it slowly push
south today and tonight. Update...front has continued south with
wind shift line from NE to SW Neb, including north winds at ODX
where temp had climbed to 101 at 2 pm CDT.
First concern involves tstm chances late this afternoon into the
evening. Not seeing much in the way of forcing in the mid/upper
levels, although we do have the weak cold front sagging into the
CWA from the north. Instability shouldn`t be an issue as ML CAPE
values are progged to be in excess of 1500 J/KG ahead of the front
while 0- 6 km bulk shear should be in the 25-30 kt range. But in
addition to the lack of a strong forcing mechanism, we are also
expecting some mid level capping with 700 mb temps in the 12-13C
range be mid/late afternoon. Moisture also lacking a bit. As is
often the case this time of the year, the question boils down to
will there be enough heating at the surface to overcome the cap.
If we do get anything to pop, a few storms could be strong/severe
with damaging winds the primary threat as forecast soundings
showing inverted V configuration. HRRR has been consistent today
showing isolated tstms over the Neb part of our CWA. Given this
and the fact it hasn`t taken much the past week to get spotty
storms, will leave slight chc going.
Several models including the HRRR and NAM nest keep precip chances
going during the daytime on Friday which seems reasonable with a
weak mid level disturbance passing through. Temps should be
around 10 degrees cooler with the cold front expected to be south
of the CWA. Precip chances look to be the best for the SW CWA
Friday night with MCS progged.
.LONG TERM...(Friday night through Thursday)
Issued at 223 PM CDT Thu Jul 6 2017
Don`t see much change in the overall pattern into the weekend as
the upper ridge is progged to remain over the Rockies with
troughing to our east. Cannot rule out weak shortwaves moving into
our area on northwest flow, but timing these more than a day out
is difficult. This is a typical pattern for this time of year.
Seasonal highs in the upper 80s/lower 90s with 20 percent chances
of afternoon/overnight tstms.
For the early to middle part of the workweek, an upper trough may
move into the northwest part of the U.S. which could dampen the
ridge and push it east and over us. Precip chances do not look as
promising depending on how warm we get in the mid levels of the
atmosphere. With the ridge overhead, temps should hot, with
mid/upper 90s expected, with some sites in our KS CWA hitting the
century mark.
&&
.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday)
Issued at 634 PM CDT Thu Jul 6 2017
VFR conditions are expected to continue throughout the TAF valid
period. The chance for thunderstorms is present tonight, but very
low and thus not included in the TAF. Thunderstorms this evening
will likely end up southwest of our KEAR and KGRI TAF sites. Best
chance, although still small of catching a shower or thunderstorm
at our TAF sites will likely be Friday morning but still too low
to include in this TAF. The wind direction will remain light and
variable tonight.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&
$$
SHORT TERM...Ewald
LONG TERM...Ewald
AVIATION...Wesely
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
609 PM CDT Thu Jul 6 2017
.SYNOPSIS...
Issued at 254 PM CDT Thu Jul 6 2017
High pressure aloft continued to dominate the weather
pattern across the western CONUS this morning with H5 hts. of 5980
meters noted at Grand Junction Colorado and at Flagstaff Arizona.
The high was anchored over the four corners with a ridging extending
north into western Canada. Upstream of the ridge, a closed low was
noted over the Gulf of Alaska. Downstream of the high and ridge, a
decent shortwave trough was noted over the lower Ohio valley. Well
north of this feature, closed low pressure was located over
Greenland with a trough extending swwd into northern portions of
Hudson Bay. Looking at WV imagery this afternoon, weak disturbances
were noted on the periphery of the high across the western CONUS.
The first wave was noted over northeastern Kansas and was
responsible for thunderstorms overnight in the eastern forecast
area. Elsewhere, weak shortwaves were noted in northern Wyoming,
southwestern Montana and southern California. The Wyoming shortwave
has spread some high cloudiness across northern Nebraska this
afternoon. At the surface, a weak trough of low pressure extended
across northwestern portions of the forecast area. Winds on the back
side of this feature were east northeast, with westerly and
southwesterly winds south of this feature. Temperatures as of mid
afternoon ranged from 94 at Gordon, to 103 at Thedford.
&&
.UPDATE...
Issued at 506 PM CDT Thu Jul 6 2017
The RAP, HRRR and NAM are carrying the disturbance over the Big
Horns through Ncntl Neb late tonight and Friday. A new forecast is
in place for this event. POPs are capped at 40 percent because
recent model inconsistencies.
&&
.SHORT TERM...(This evening through Friday)
Issued at 254 PM CDT Thu Jul 6 2017
Tonight through Friday night: Thunderstorm chances
over the next will be the main forecast challenge in the short term.
For tonight: The shortwave, over sern Montana, will approach eastern
Wyoming early this evening leading to the development of
thunderstorms. H5 flow will remain northwesterly tonight and any
activity which does develop, will track into western and
southwestern portions of the forecast area. Deep layer shear this
evening is favorable for rotating thunderstorms, however, very
meager CAPE exists, so any storms which do develop will be elevated
with gusty winds and lightning being the main threats. With the very
dry conditions recently, as well as the expected elevated nature of
storms, will continue to mention a dry lightning threat in the HWO.
Overnight tonight, high pressure will build into the Dakotas,
forcing a weak back door cold front through the forecast area. On
Friday, the front will lie down from southeastern Wyoming into
western Kansas. Cooler temperatures will reside north of the front
with highs Friday in the mid to upper 80s. With the front south of
the area, easterly winds Friday, will allow low level moisture to
pool across western portions of the forecast area. Add in surface
heating and an approaching shortwave, the threat for thunderstorms
will increase late Friday afternoon into Friday night. Attm. with 40
KTS of bulk shear Friday evening and SB capes around 2000 J/KG,
there seems to be a better setup for severe storms over the setup
for tonight-particularly in the west.
.LONG TERM...(Friday night through Thursday)
Issued at 254 PM CDT Thu Jul 6 2017
Saturday through Sunday: Thunderstorms across western and
southern Nebraska Saturday night, will shift south into northern
and central Kansas Saturday. The front will remain anchored well
off to the south of the forecast area Saturday into Saturday
night, with the best low level moisture pooling INVOF the front in
central and southern Kansas. This will lead to mainly dry
conditions for the mid range period and will leave the forecast
dry attm. The front will wash out across Kansas Saturday night
with much warmer air pushing into the region for Sunday. After
highs in the upper 80s to around 90 for Saturday, highs will reach
the mid to upper 90s for Sunday.
Sunday night through Thursday: Upper level high pressure will
meander from the central Rockies, onto the central plains next week.
Hot temperatures are likely with most days seeing highs from the mid
90s to the lower 100s. Confidence in the temperature forecast is
high at this juncture as both the ECMWF and GFS mos guidance show
strong agreement with their forecast highs next week. Precipitation
chances remain meager during the period though as storms will be a
result of weak disturbances rotating around the northern periphery
of the high.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 609 PM CDT Thu Jul 6 2017
The RAP, HRRR and NAM are carrying the disturbance over the Big
Horns through Ncntl Neb late tonight and Friday. This should
result in an area of scattered to numerous thunderstorms affecting
Ncntl Neb from about 05z tonight through 15z-18z Friday.
The area of thunderstorms across Swrn Neb should exit the region
by 02z.
Otherwise VFR is expected overnight through Friday afternoon.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...CDC
SYNOPSIS...Buttler
SHORT TERM...Buttler
LONG TERM...Buttler
AVIATION...CDC
Area Forecast Discussion
National Weather Service Lake Charles LA
710 PM CDT Thu Jul 6 2017
.DISCUSSION...
Radar showing a collection of thunderstorms with multiple colliding
outflow boundaries across NE TX/NW LA continuing this evening,
moving to the SE. HRRR guidance shows this continuing the next 2-3
hours before finally dissipating with the loss of daytime
heating, but not before moving across Northern Tyler/Jasper/Newton
counties in SE TX & Vernon/Rapides in C LA. Updates this evening
include increasing pops to 30-40% across this region for the
expected showers and thunderstorms through this period. Activity
should be diminishing by 10 PM to midnight. No other changes made.
DML
&&
.PREV DISCUSSION... /issued 645 PM CDT Thu Jul 6 2017/
AVIATION...A few showers and storms are expected near KAEX
through the next few hours, then across the whole area tomorrow
afternoon, but overall mostly VFR conditions are expected. A brief
period of lower vis will be possible in showers and storms.
Outside of storms, light south to southwest winds are expected
through the period.
PREV DISCUSSION... /issued 349 PM CDT Thu Jul 6 2017/
DISCUSSION...
Upper trof axis to the west is in the process of shearing apart as
jet energy dives SE from Canada through the Northern Plains/Upper
Midwest, which is forecast to yield an eroding subtropical ridge
and mean ERN CONUS trof over the weekend downstream of an already
present robust ridge over the Four Corners. Meanwhile, an upper
low and associated weak inverted low/mid level trof was noted over
the NW Gulf just off the TX coast, which is progged to continue
WWD tonight and FRI.
More in the way of afternoon showers and thunderstorms today as
higher PW air associated with the inverted trof filters into the
region, with convergent cloud bands, the sea breeze, and
subsequent convective outflows serving as initiation points.
Above normal rain chances are forecast to continue for the next
several days as MSTR pooled along a stationary front to the north
sags slowly southward and higher PW air continues filtering into
the region from the S/SE as the inverted trof over the Gulf moves
into TX. In addition, a weak front is forecast to sag into the
area on SUN, providing an additional focusing mechanism.
PoPs are still expected to decrease a bit through the upcoming
week as the ERN CONUS trof lifts out and the WRN CONUS ridge
shifts eastward over the Plains, but at the same time the
subtropical ridge will become re-established to our east,
resulting in a moist low/mid level onshore flow.
Little variation in temperatures is expected through the forecast
period other than local moderation by convection. Daytime highs
are expected to climb to around 90, with overnight lows falling
into the mid/upper 70s.
13
MARINE...
A light onshore flow and low seas will prevail through the period
as high pressure remains to our southeast. Isolated to
scattered showers and thunderstorms are possible each day.
13
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 74 93 76 92 / 40 40 20 40
LCH 78 90 78 91 / 20 50 10 40
LFT 76 90 76 90 / 20 50 10 50
BPT 76 90 75 90 / 20 40 10 40
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...None.
TX...None.
GM...None.
&&
$$
PUBLIC...08
Area Forecast Discussion
National Weather Service Marquette MI
734 PM EDT Thu Jul 6 2017
.SHORT TERM...(This evening through Friday)
Issued at 423 PM EDT THU JUL 6 2017
WV imagery and RAP analysis indicated a mid/upper level ridge over
the cntrl/srn Rockies and a trough over ne Canada resulting broad
cyclonic wnw flow through the nrn Great Lakes. The combination of a
weak shortwave and convergence along a cold front extending from the
srn end of James Bay to ne MN supported thunderstorms from west of
CYQT into the MN arrowhead. In the wake of the shra/tsra this
morning into early afternoon, capping remained over Upper Michigan,
per 18z GRB sounding, with mostly sunny skies over the west half and
a only a few shallow cu.
Tonight, expect sct tsra to redevelop this evening over the wrn cwa
as the front and shrtwv approach, per upstream trends and short
range highs res model guidance. Dewpoints in the lower 60s and temps
into the lower 80s over the interior west have resulted in MLCAPE
values into the 1k-2k range. The instability along with 0-6km shear
to around 40 knots will support strong storms with a few possibly
becoming severe with damaging winds as the main hazard. The
convection should move through the area quick enough to clear the
se portion of the area by 05z. Cooler drier air moving overnight
will allow temps to drop into the mid 50s.
Friday, nrly flow will bring in enough 900-700mb moisture for mostly
cloudy skies. The onshore north flow over the north will keep temps
in the low to mid 60s while readings over the south climb into the
lower 70s. Some isold light showers may also be possible over the
south in the afternoon where some weak instability (CAPE to near 500
J/Kg) will develop.
.LONG TERM...(Friday night through Thursday)
Issued at 342 PM EDT THU JUL 6 2017
Minor changes to the overall longterm pattern, with ridging trying
to amplify across the Northern Rockies then retrograding west by the
second half of the weekend. Downstream 500mb trough over Hudson Bay
will remain through the weekend, with a few weak lobes vorticity
traversing the southwest side and over the Upper Peninsula.
A weak frontal boundary will push southeast through the region Fri
aftn/eve, with broad surface riding returning and providing seasonal
temps and dry weather for Fri ngt/Sat. Another weak wave will then
arrive under the northwest flow later Sat and bring a chance for
showers and perhaps an isolated thunderstorm. Then periodic chances
for showers again Sun with temps remaining in the 70s and overnight
lows in the mid/upr 50s. Later in the extended periods the 500mb
ridge across the western CONUS will begin to flatten allowing a
quasi-zonal orientation to the longwave pattern. This will bring
some moderation to the temps late in the extended with periodic
chances for showers and perhaps thunderstorms.
&&
.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 724 PM EDT THU JUL 6 2017
Mainly VFR conditions are expected through the forecast period.
Scattered showers and thunderstorms are rolling through western
Upper Michigan at this time ahead of a cold frontal passage.
Expect tsra to affect IWD through 01z and SAW from 01-03z. It
looks like tsra will split south and north and not impact CMX.
There is a potential that lake MVFR fog/stratus could affect the
western TAF sites of IWD and CMX later this evening given the fact
that storms have moved over the lake and expected onset of north
winds behind cold front. Expect VFR through the day on Friday.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 423 PM EDT THU JUL 6 2017
Northerly wind of 10 to 20 knots are expected late tonight into
Friday behind a cold front. Winds should also increase to around 20
knots Saturday ahead of another trough approaching the area from the
northwest. Otherwise, Wind conditions across the lake should remain
tranquil through the forecast period with winds staying below 20
knots.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...Beachler
AVIATION...Voss
MARINE...JLB
Area Forecast Discussion
National Weather Service Blacksburg VA
1138 PM EDT Thu Jul 6 2017
.SYNOPSIS...
An upper level trough of low pressure over the Mid-Mississippi
Valley will continue to eject upper level disturbances across
the forecast area through Friday with an opportunity for
showers and thunderstorms. A cold front will sweep through the
area Saturday with a period of drying Sunday and Monday.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 1132 PM EDT Thursday...
Severe threat seems over, with only a few thunderstorms around
in the mountains until 1-2am. HRRR and RAP showing showers
lingering over the WV mountains overnight thanks to an upper
level shortwave situated in the central Appalachians. Further
south and east a few showers still possible but overall trend
is for less coverage overnight. Added patchy fog in as thinking
in the Piedmont clearing taking place with earlier rain will
promote fog development.
Previous discussion from early evening...
Moist/unstable airmass still leading to scattered convection
across the area, namely east of the Blue Ridge. Mesoanalysis
and satellite showing 2-3 areas of higher potential for
convection, one east of the piedmont, then another along a
theta-e sfc gradient from the NC Triangle area west to the
foothills, then across eastern KY/far SW VA.
Per latest high-res models favored more coverage east and west,
with less in the New River Valley early on, then shift more
concentration west ahead of better upper energy moving across
the Ohio Valley into WV after midnight.
Previous discussion from mid afternoon...
Several upper level disturbances will rotate eastward across the
region in the westerly upper level flow. The broad upper level
trough in the Ohio Valley will pivot eastward and amplify along the
East Coast during the weekend.
Scattered afternoon and evening showers and thunderstorms will
develop in the unstable air. The larger-scale forcing mechanisms are
hard to find. However, weak upper features combined with low level
boundaries and surface convergence, orographic lift with a healthy
instability should trigger convection. The 17z SPC mesoscale
analysis displayed sbcapes from 1000 to 2500 j/kg across forecast
area this afternoon.
There is a marginal threat for severe weather as highlighted on the
Day One Convective Outlook across the entire forecast area for this
afternoon and evening. The primary threat will be damaging winds
with water loading and thunderstorm clusters or line segments.
The potential for torrential downpours continues with high PWATs
above 1.5 inches and healthy rain efficiency. Will have to monitor
for water problems that received heavy rains recently. However,
the DAY 1 excessive rainfall placed marginal risk to our west
and north.
It will be another mild night with low temperatures from around 60
degrees in the mountains to around 70 degrees in the Piedmont.
The combination of light winds and low level moisture may result in
patches of fog overnight into Friday morning especially where it
rains.
As the upper trof settles in over the Eastern United States on
Friday, the initial shortwave will push through early Friday and
move a weak front across across the area. This looks like a
more progressive system which would allow some drier air to mix
down as Friday progresses. The latest Day 2 Convective Outlook
has a marginal risk of severe thunderstorms across southeast
West Virginia. The main threats will be damaging winds and heavy
downpours. High temperatures Friday will range from the lower
70s in the mountains to the near 90 degrees in the Piedmont.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 222 PM EDT Wednesday...
Some colder air aloft and a shortwave in the northern stream
trof Saturday, so locations ahead of the front will have
scattered thunderstorms in the afternoon. Models showing upper
diffluence too during Saturday. Not much backing of the winds to
the southwest ahead of the front. NAM/GFS/ECMWF/GEFS suggests
no precipitation in the Virginia and North Carolina piedmont
Friday night, perhaps because of deep western flow.
Have minimum temperatures Friday night ahead of the front
slightly warmer than guidance. Models consistent bring in lower
surface dewpoints and relatively cooler 850mb temperatures by
Sunday morning.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 1245 PM EDT Thursday...
Starting with a 500 MB ridge from the southwest United States
to the northern Rockies and a long wave trough over the east. By
Thursday morning, the upper ridge will progress into the center
of the country. A short wave coming out of Pacific Northwest
over this ridge may reach the northeast United States on
Tuesday, potentially pushing a surface cold front toward the Mid
Atlantic region. Will have the highest probability for showers
and thunderstorms on Wednesday. 850MB temperatures warm back up
into the +16 to +20 range for Monday through Thursday. This will
keep temperatures just above normal for much of the week.
&&
.AVIATION /04Z FRIDAY THROUGH TUESDAY/...
As of 730 PM EDT Thursday...
Aviation conditions will be centered on convection into tonight,
especially BLF/LWB where upper support and models showing better
threat. Given this highly moist airmass a potential always
exists for dense fog and/or low clouds to form overnight. With
cloud cover around per convection will have to wait and see if
things stay clear enough for low level moisture to lead to
fog/low clouds. Confidence is higher that at least MVFR and
possibly IFR occurs at most sites.
Models showing more of a morning threat of showers/storms in the
west then sliding the threat east of our area after 18z. Morning
hours can be highly variable with low cigs/showers around in the
mountains, and possibly into the foothills east of ROA.
Think by 18z Friday most if not all taf sites will be VFR.
Medium confidence on ceilings, visibilities and winds during
the taf period.
Extended Aviation Discussion...
Another upper impulse moves in Friday night/Saturday morning
with showers and some storms situated mainly west of ROA-BCB.
Potential for areas of MVFR and local IFR conditions with these
showers. Generally VFR conditions are anticipated for the
weekend as dry northwesterly winds develops for a few days. MVFR
conditions could return Monday and Tuesday with showers and
thunderstorms, and possibly late night fog.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...KK/PM
NEAR TERM...KK/WP
SHORT TERM...MBS
LONG TERM...AMS
AVIATION...KK/PM/WP