Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 08/15/19
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
552 PM MDT Wed Aug 14 2019
.AVIATION...
00Z TAF CYCLE
Showers and thunderstorms will continue to shift E-SE through the
evening, potentially impacting KTCC and KROW over the next several
hours before diminishing. Localized MVFR conditions in heavy rain
will be possible. Small hail and gusty outflow winds are also
possible. Current outflow boundary collisions near KAEG and KABQ
have not produced additional thunderstorms, thus the window for
storms at these locations is closing. The few showers and
thunderstorms persisting across the west will diminish by sunset. On
Thursday, though a few storms will be possible across northern NM,
the focus should be across the high terrain south of I-40.
34
&&
.PREV DISCUSSION...320 PM MDT Wed Aug 14 2019...
.SYNOPSIS...
Storms stretching from the Continental Divide to the central
mountain chain this afternoon will continue to track into the
eastern plains this evening, where a few could become strong to
severe with large hail and damaging winds. Thunderstorm coverage
trends downward Thursday and Friday as temperatures warm a little
across much of the state. Even drier conditions expected for the
weekend when portions of the east central and southeast may
experience near record highs. Storms could return to northern and
central New Mexico early next week.
&&
.DISCUSSION...
Drier air continues to reside over portions of northwest New Mexico,
while the boundary that pushed to the Continental Divide was the
focus for storm development this morning and early this afternoon.
With the upper high centered over western NM/eastern AZ, storms will
be moving to the east and southeast. Expect that the majority of the
current activity will be focused along and south of I-40 and along
and east of I-25 later this afternoon and early this evening,
propagating into the eastern plains, where a few strong to severe
storms with large hail and damaging winds are possible. Both the
RAP13 and HRRR hold onto some precipitation after midnight over the
eastern plains, but the RAP13 has much more lingering after midnight
over the west central and southwest, so will have to monitor for
this potential.
Drier air is still expected to make additional progress over
northern and central NM Thursday and Friday, as the flow aloft
trends more westerly. Storms will favor the southern high terrain
where moisture will be tougher to sweep out. High temperatures will
warm a few degrees and overnight lows over some of the northwest and
north central should be a bit cooler. The weekend appears even drier
with a dearth of storms. The southwest mountains would be the most
likely place to see a few storms. There could be some near record to
record highs over the east central and southeast, with Roswell on
track to experience several days in a row of 100 degree plus
temperatures, topping out on Sunday at 105.
The upper air pattern changes early next week, reverting to a ridge
centered over NM. Some moisture may seep back into the region, and
high temperatures may cool a few degrees over the eastern plains as
the the GFS drifts the center of circulation towards CO by next
Tuesday. The ECMWF positions the high center over AZ by the middle
of next week. Either way, monsoon storms will likely remain fewer in
number for mid August.
&&
.FIRE WEATHER...
Hot, dry and unstable conditions prevail today across far northwest
New Mexico, but a backdoor front pushed west to the Continental
Divide this morning and brought added moisture and cooler
temperatures to central and eastern portions of the state. The added
moisture is resulting in a round of wetting storms, which will
impact much of central and northeast New Mexico this afternoon and
evening. Otherwise, a warming and drying trend is forecast for at
least the northern half of the state over the next several days as
the westerlies penetrate further east. This will result in an
expansion of hot, dry and unstable conditions through at least
Sunday as the upper high sets up south of the state. The upper high
is forecast to move to near the Four Corners or southern Colorado
next week, which may allow moisture to come up from the south and
result in the return of chances for wetting storms. Until then,
expect above to well above normal temperatures and worsening
humidity recovery.
11
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
852 PM CDT Wed Aug 14 2019
.UPDATE...
Issued at 849 PM CDT Wed Aug 14 2019
Overall the forecast is working out okay, but did make a few
tweaks to PoPs based on latest HRRR output. The rest of the
forecast elements look okay.
&&
.SHORT TERM...(This Evening through Thursday Night)
Issued at 335 PM CDT Wed Aug 14 2019
Surface heating cu across the region under surface high pressure
will dissipate into the evening hours. Otherwise, expect mostly
clear skies tonight with some waa/mid level accas storms possible
mainly late tonight out west in advance of an approaching short wave
trough. There also may be some patchy fog in the east later tonight.
On Thursday, the ops models and high-res models all show better/more
numerous storm development on Thursday afternoon into the evening
with lift from a short wave trough and surface front moving in.
Cloud cover and morning storms could affect the build up of
instability for storms in the afternoon and evening. At this time,
expect there to be plenty of mucape/instability along with good deep
layer shear from 35 to 50 knots. Therefore, expect storms to develop
with some being supercells/possibly severe as they move southeast
with the associated upper trough and surface cold front. Have in the
best chances of storms in the afternoon/early evening across the
cwa. The severe weather slight risk area had been expanded across
most of the cwa for this time. The storms will leave the eastern cwa
Thursday night with cooler and drier north winds in behind them.
.LONG TERM...(Friday through Wednesday)
Issued at 335 PM CDT Wed Aug 14 2019
Progressive zonal to northwesterly flow will continue at 500mb
through Sunday night. A few disturbances rolling trough will help
trigger wet weather. Friday afternoon and evening will have the
highest chance of showers and thunderstorms over our southern
counties, with most of the activity being across NE. The focus will
then shift to our eastern counties Saturday morning through Sunday
night. 850mb temperatures will briefly fall to 10-13C again Saturday
afternoon and evening. Depending on cloud cover, we may need to cut
back on the upper 70s surface temperatures currently forecast for
Saturday afternoon. The cool down will likely be short lived 850mb
temperatures rebound to 16 to 22C Sunday afternoon, at least off the
12Z GFS. Just how quickly we return to southerly flow will impact
our temperatures Sunday. NBM looks a little slow/cooler than some of
the operational models to bring back the warmer air, and there is
plenty of uncertainty.
It`s more likely that we will return to temperatures that are more
typical for this time of year on Monday. This is when the 500mb high
across the south central U.S. pushes a ridge across South Dakota and
west central MN through much of the rest of the long term period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 641 PM CDT Wed Aug 14 2019
VFR skies/vsbys are expected through tonight, although there could
be patchy fog toward morning. Not confident enough to include in
forecast at this time.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...TDK
SHORT TERM...Mohr
LONG TERM...KF
AVIATION...TDK
Area Forecast Discussion
National Weather Service Denver/Boulder CO
830 PM MDT Wed Aug 14 2019
.UPDATE...
Issued at 830 PM MDT Wed Aug 14 2019
The airmass on the plains remained to stable to support any
afternoon convection and the main storm ended up being a lone
supercell moving southward from Yuma County. A few more weak
showers tried to develop over northern Weld County, but they are
now ingesting the cool and stable air left over from the earlier
shower activity. As the outflow reaches the foothills, the airmass
is expected to remain too stable for any nocturnal convection to
develop. Skei sshould remain mostly clear. High resolution models
do not advertise any fog or low clouds as winds are expected to
become drainage southerlies which keep the low levels dry
overnight.
The forecast has been updated for the canellation of the Severe
Thunderstorm Watch and to remove the mention of thunderstorms
overnight.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 329 PM MDT Wed Aug 14 2019
Current GOES-16 data and surface observations show the surface
boundary, separating much more moist low-level air from a bit
drier air to the west, across the far northeast corner of
Colorado. Dewpoints are still in the low 60s with ESE winds east
of the boundary, while west of the boundary dewpoints are in the
mid to upper 50s with SW winds. We don`t expect the boundary to
light up this afternoon in Colorado, it`s not a sharp gradient and
it is fighting mid-level subsidence from the departing short wave
trough. However, convection is expected to initiate in Wyoming
and then roll off the Cheyenne Ridge 4 PM or so. Storm coverage
will be minimal, as we expect any storms to form to be isolated,
perhaps just a couple of them. MLCAPE and shear profiles are
enough for supercells, with the main threat giant hail and
possibly a tornado. They should move ESE across northeast
Colorado, generally east of a line from Cheyenne to Fort Morgan to
Burlington. Elsewhere, instability is limited, and shear a bit
weaker. Weak convection is occurring across the Palmer Divide
presently, and this activity should move off to the east across
Lincoln County. Severe weather potential is more limited to the
south but lightning and marginally severe hail are possible,
especially as they move into Lincoln County. Storm chances are
very low for the I-25 urban corridor and the high country,
especially west of the Continental Divide.
Convective activity should wind down across our area after 11 PM.
The chance of a repeat of last night`s convection along I-25 is
much lower than last night. Instability is less, there is mid-
level subsidence, and the strength of the gust front should be
less given the expected isolated nature of the storms this
afternoon/evening. Still, can`t rule it out so will preserve
10-20% PoPs east of the foothills through midnight. Clearing skies
and lows in the 50s across the plains, and around 60 in the urban
heat islands. Mountains should cool into the 40s.
On Thursday, weak WNW flow continues across Colorado with a
dominant sub-tropical ridge over the desert southwest. PW values
drop to 0.5" across the front range in the dry WNW flow, but
still 1.0" across the far eastern plains. A moisture gradient will
set up again across the far eastern plains and thus there is a
slight chance of thunderstorms for the far northeast corner. Any
storms that manage to develop could be severe with large hail.
Elsewhere, convective chances are low. Just a slight chance of a
weak thunderstorm across the Palmer Divide. 700 mb temperatures
warm a few degC, so highs should be 90-95 across the plains,
especially given even less afternoon cloud cover. Expect 70s to
low 80s in the high country, with 50s above treeline.
.LONG TERM...(Thursday night through Wednesday)
Issued at 329 PM MDT Wed Aug 14 2019
There will be a few more weak shortwaves moving over the northern
Rockies through Saturday, then the upper ridge will build
northward over Colorado. Dry and hot air aloft will be moving over
from the west, but there will still be some low level moisture
over the plains on Friday. Models have had pretty good agreement
on a shallow surge of moist and possibly cooler air over the
plains, but they disagree on the strength of this. The NAM
actually keeps temperatures in the 70s near the eastern border
Friday afternoon, which looks overdone. There will likely be some
stratus that could hold on long enough to impact the temperatures
by a few degrees though, which in turn could restrain convection.
Moisture should mix out pretty well further west, so if there are
any storms they should be on the dry/windy side. Still a threat of
severe storms over the eastern plains if/when it gets warm enough
late in the day.
Saturday looks like a transition day as the ridge builds. The
westerly flow aloft should bring continued drying, but there may
still be enough moisture left, and a little lift from the last
effective shortwave passing north of us, for some isolated
convection. The combination of heat/dry/breezy/isolated storms
raises fire weather concerns for Friday and Saturday--see below
for more on that.
For Sunday into next week, the ridge will be overhead with hot dry
air. The models are still producing some convection to create
mid/high clouds each afternoon, but not any precipitation. This
could restrain highs a little, but only if it develops early
enough in the day. We nudged highs a couple of degrees warmer than
the model blends for Sunday and Monday, with highs in the mid to
upper 90s on the plains which will be near the records for those
days. The trend in the models is toward holding the ridge
stronger over the central Rockies or shifting it a bit further
west which would shield us from much moisture import through the
week. There will still likely be a gradual northward creep of
moisture, enough for some late day storms mainly over the
mountains, but maybe not much in the way of rain or cooling if the
latest trends turn out to be correct.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 830 PM MDT Wed Aug 14 2019
The outflow boundary from this evening`s convection over the far
northeast plains will be reaching KDEN before 9 PM with easterly
gusts up to about 25 knots. Although dew points will be rising
with the arrival of the outflow boundary, the HRRR model shows the
winds turning to drainage southerlies by 11 PM and no fog is
expected. Winds are expected to become westerly through the day
tomorrow, so the only aviation impacts should be the gusty winds
between 845 and 10 PM.
&&
.FIRE WEATHER...
Issued at 329 PM MDT Wed Aug 14 2019
Hot temperatures and moderate westerly flow aloft will combine
with low humidities to create conditions near Red Flag criteria
over the mountain valleys and foothills on Friday and Saturday
afternoons, with minimum humidities around 15% and wind gusts in
the 20-30 mph range. At this point, the worst conditions are
expected Friday afternoon. Fuels will continue to dry and may be
dry enough for rapid fire growth in the areas that have received
less rain over the last month. Hot and dry conditions will
continue into next week, but winds will be lighter.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Dankers
SHORT TERM...Schlatter
LONG TERM...Gimmestad
AVIATION...Dankers
FIRE WEATHER...Gimmestad
Area Forecast Discussion
National Weather Service Caribou ME
1043 PM EDT Wed Aug 14 2019
.SYNOPSIS...
High pressure in Ontario will slowly build toward the region
through tonight. The high will settle into Maine Thursday
before moving east Friday. A southwest flow will develop across
the area over the weekend and into Monday.
&&
.NEAR TERM /THROUGH THURSDAY/...
1025 PM Update...Clouds continue to hang on per the latest satl
loops showing some clouds extending from NE Maine down into SW
Maine. Most of the cloudiness was sct-bkn w/bases at 7k ft. 00Z
UA showed a trof axis across the region w/some moisture showing
up around 850 mbs. This trof was aiding the clouds. The last
few runs of the RAP showed the clouds starting to break up after
06z as some high pres ridging takes hold. Temps were adjusted to
match to the current obs. Overnight forecast lows look w/in the
ballpark attm.
Previous Discussion...
High pressure will be moving across the region overnight into
Thursday. Patchy fog around lakes and rivers early morning then
lifting then scattered cumulus clouds building. Not as cool
tonight with lows in the lower 50s. Pleasant tomorrow with highs
in the low 70s north, mid 70s central and southern portions of
the forecast area.
Loaded a blend of the GFS/NAM/ECMWF/GEM to smooth out the minor
differences in the models.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
A low will track into the state early in the period, bringing
rain to the area. The low will track from SW to NE Maine and
exit the area early Saturday morning, higher pressure will
briefly build into the area ahead of another system. Early
Sunday morning a warm front pushes into western Maine border
with Quebec, by morning it will move into central Maine bringing
another round of showers to the area. By the end of period
Sunday evening it will exit the region into New Brunswick.
Loaded a blend of the GFS/NAM/ECMWF/GEM to smooth out the minor
differences in the models.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Upper level westerly flow will be over the region Sunday through
Wednesday. Will be difficult to time shortwaves this far out in
this pattern, but there appears to be a chance of precipitation
most days. Warm and muggy as well especially Sunday and Monday,
which also appear to be the days with the best shot at showers
and storms at this point. Most models have slightly drier air
moving in Tuesday and Wednesday behind a weak cold front with
temperatures dropping from above average to near average.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR conditions through the period, patchy morning fog
in and around lakes and rivers. The fog will lift by mid morning
then sct cu will develop.
SHORT TERM: Thursday evening through Monday... VFR conditions early,
falling to MVFR in showers for FVE, CAR, PQI, and HUL as a low
pressure system tracks across the northern half of the state.
The low will clear the area early Saturday morning and higher pressure
will briefly build in.
Saturday Morning...MVFR conditions will remain across northern Maine
until the next system moves into central Maine. Northern
sites will fall to Low MVFR to IFR conditions in showers. These
conditions will spread to BHB and BGR Saturday evening.
Monday morning...This system will clear the area, VFR conditons will
return to all sites. Patchy fog near rivers and lakes during the
early morning hours, otherwise VFR through the end of the
period.
&&
.MARINE...
NEAR TERM: Winds and seas below Small Craft Advisory levels
through the period.
SHORT TERM: Winds and seas below Small Craft Advisory levels
through the period.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...None.
&&
$$
Near Term...Hewitt
Area Forecast Discussion...UPDATED
National Weather Service Cheyenne WY
601 PM MDT Wed Aug 14 2019
.UPDATE...
Issued at 549 PM MDT Wed Aug 14 2019
Please see updated 00Z aviation discussion below.
&&
.SHORT TERM...(This evening through Friday)
Issued at 240 PM MDT Wed Aug 14 2019
Short term concerns will be on convective potential and coverage
through Friday. Right now quiet over the CWA as inhibition and
lack of any forcing has prevented all but a few brief showers
around the mtns so far. HRRR/NAM remaining quite sparse on
activity the rest of this afternoon into this evening with just a
few indications near the Colorado border over the next few hours.
A somewhat better chance for some strong storms looks to occur
later tonight over far northern parts of the CWA as a shortwave
clips that area but latest HRRR has also backed off on that
activity.
Not much change seen for Thursday with best chances for convection
over northern parts of the CWA in the afternoon with another weak
impulse passing by. Sfc boundary will be banked up against the
mtns Thursday through Friday keeping temperature over the plains
on the mild side for this time of year. Modest upslope flow will
keep chances for convection going through Friday.
.LONG TERM...(Friday night through Wednesday)
Issued at 240 PM MDT Wed Aug 14 2019
A drier pattern looks to set up over the area this weekend into
early next week as the westerlies lift northward and upper ridging
strengthens over the area. A mostly westerly upper flow will be
over the region with moisture limited so only isolated late day
showers and storms seen, mainly Weds. Turning warmer Sunday with
quite warm conditions remaining into early next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 549 PM MDT Wed Aug 14 2019
Conditional aviation impacts possible this evening and partially
overnight with isolated/scattered TSRA near KCDR/KAIA 06-09Z
tonight. Isolated -SHRA will also be possible near KCYS through
03Z tonight. Some Hi-res models indicate the TSRA possible near
KCDR/KAIA could be farther east in central Nebraska. The next
aviation impact will be patchy fog and low ceilings in the
Nebraska Panhandle with highest confidence near KBFF/KAIA/KSNY
from 10-15Z Thursday morning. Thereafter, VFR conditions are
expected through the day. Surface winds will be southeasterly for
the Nebraska Plains and west in the high terrain at 10 to 15
knots overnight and then increasing again Thursday afternoon with
gusts upwards of 20 to 25 knots.
&&
.FIRE WEATHER...
Issued at 240 PM MDT Wed Aug 14 2019
Overall Fire weather concerns look to remain on the low side with
fuels still mostly non-critical. Exceptions will continue to be
over southwestern Carbon county where winds and low afternoon
humidity will continue to produce near critical to critical
conditions again Thursday. Otherwise widely scattered showers and
storms will move over parts of the area at times tonight through
Saturday before drier conditions settle in Sunday into early next
week.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Red Flag Warning until 8 PM MDT this evening for WYZ304.
Fire Weather Watch from Thursday afternoon through Thursday
evening for WYZ304.
NE...None.
&&
$$
UPDATE...JSA
SHORT TERM...RE
LONG TERM...RE
AVIATION...JSA
FIRE WEATHER...RE
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1050 PM CDT Wed Aug 14 2019
.UPDATE...
New storms have developed along the gust front south of I-10. Cells
are showing signs of weakening as the cold pool is starting to move
away from the convection. Have adjusted POPs to show rain chances
farther south. We have also removed POPs overnight. Short term models
show this as the last round.
&&
.PREV DISCUSSION... /ISSUED 857 PM CDT Wed Aug 14 2019/
UPDATE...
A second line of showers and thunderstorms is moving through the
eastern part of the CWA. This line will continue for another hour or
two. We are starting to see the outflow becoming dominant which
suggests the storms losing energy. Convection has ended out west. We
have adjusted the POPs for the rest of the evening to reflect these
developments. We have also made some adjustment to the POPs for
Thursday. With the convection we`ve had today, chances for
development seem less likely Thursday, so we have reduced POPs across
the area. It sill looks like there will be a slight chance across the
north and east with a bit higher chance over the southeast. But, most
places will probably be dry.
PREV DISCUSSION... /ISSUED 640 PM CDT Wed Aug 14 2019/
UPDATE...
A broken line of showers and thunderstorms is moving southward
through our CWA. This line stretches from Blanco to Del Rio. It has
been slowly weakening as it moves south and this trend should
continue as the sun sets and the convection pushes more stable air
ahead of it. We have adjusted the POPs in the short term to reflect
this situation, increasing them a little farther south and decreasing
them behind the line. Some places have had significant cooling with
rain: Fredericksburg dropped to 77 degrees after a rain shower. It
might be hard to keep up with hourly temperatures where there is
rain cooled air. But temperatures should rebound once warmer air
mixes back in.
PREV DISCUSSION... /ISSUED 627 PM CDT Wed Aug 14 2019/
AVIATION /00Z TAFs/...
VFR conditions are expected to prevail through the TAF period, save
for temporary drops to MVFR should TSRA impact DRT through sunset. A
series of southward-sagging outflow boundaries and stationary front
bisecting Central Texas will continue to serve as foci for TSRA
development through early evening before loss of heating allows for
convection to wane. Have removed VCSH mention from SAT/SSF as current
motion keeps outflow north and west of the San Antonio terminals
until closer to 04-06Z and will handle any lingering TSRA/SHRA with
amendments if needed. Outflow has cleared DRT this evening and with
visible satellite showing new updrafts forming behind it have added
a TEMPO TSRA mention for DRT through 01Z. 20-30 knot gusts will be
possible in the vicinity of TSRA. Otherwise, outflow approaching AUS
may result in isolated SHRA development near the terminal and a
northerly wind shift between 01-02Z.
Light and variable winds are expected overnight in the presence of
these boundaries with heating resulting in a secondary round of
SHRA/TSRA development late in the TAF period as convective
temperatures are reached. Have introduced VCSH starting 18-20Z for
all South Central Texas terminals for Thursday afternoon with
additional refinements to timing likely as boundary positions become
better defined during the day Thursday.
PREV DISCUSSION... /ISSUED 230 PM CDT Wed Aug 14 2019/
SHORT TERM (Tonight through Thursday Night)...
Weak boundary north of the region has had just enough low level
convergence to get showers and thunderstorms going this afternoon
aided by daytime heating. Scattered rain chances this afternoon and
evening are for areas west of I-35 and north of US-90. Rain chances
linger into tomorrow in association with the passage of this
boundary. As a result, temperatures should be a couple degrees below
what they have been earlier in the week for most of the area.
However, eastern areas will still be near heat advisory criteria.
Forecast soundings from Del Rio and Austin tomorrow afternoon show an
inverted V pattern in the lower levels with elevated DCAPE values
near 1500 J/Kg. If a thunderstorm or two were to get going tomorrow,
the biggest threat will be strong winds.
There is model disagreement for tomorrow`s possible activity with
the ECMWF keeping the region mostly dry, GFS and NAM are more robust
with the convection. Latest runs of the NMMB and HRRR also suggest
scattered convective activity Thursday. Not anticipating much in the
way of accumulation, most areas will be lucky if they get a tenth of
an inch, isolated amounts could be higher.
LONG TERM (Friday through Wednesday)...
By Friday the forecast enters another dry and warming trend as the
subtropical high continues to remain anchored over the state.
Temperatures will climb back to the century mark for most places and
heat advisory criteria will likely be met for our eastern counties
with heat index values forecasted to be 108-110 early next week. Near
the end of the period, a weakness in the ridge develops east of the
Mississippi River Valley and may allow disturbances to ride around
the edge of the high as it is suppressed to the west and bring
chances for rain to South Central TX. Looking beyond the long term
period (famous last words of a meteorologist) long range model
guidance is beginning to suggest a tropical wave amplifying as it
moves out of the western Caribbean and into the southern Gulf of
Mexico. It is far too early to know what will come of this
disturbance.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 79 98 78 100 78 / 20 20 0 - 0
Austin Bergstrom Intl Airport 78 98 77 99 77 / 20 20 0 - 0
New Braunfels Muni Airport 77 98 76 99 76 / 20 20 - - 0
Burnet Muni Airport 76 96 75 98 75 / 20 20 - - 0
Del Rio Intl Airport 80 102 80 104 80 / 30 10 10 0 0
Georgetown Muni Airport 77 98 77 100 77 / 20 20 0 - 0
Hondo Muni Airport 77 101 76 102 76 / 30 20 - - 0
San Marcos Muni Airport 77 98 76 99 76 / 20 20 - - 0
La Grange - Fayette Regional 78 99 77 100 78 / 20 30 0 - 0
San Antonio Intl Airport 79 98 78 99 78 / 20 20 - - 0
Stinson Muni Airport 79 98 78 99 78 / 20 20 0 - 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Aviation...Huffman
Short-Term/Long-Term...05
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1012 PM EDT Wed Aug 14 2019
.SYNOPSIS...
Slightly drier air will filter into the forecast area to end the
work week, limiting chances for afternoon and evening storms
Thursday and Friday. Moisture will begin increasing again by the end
of the weekend as a Bermuda high strengthens over the western
Atlantic Ocean. A weak area of tropical low pressure and associated
moisture may impact the Southeast early next week.
&&
.NEAR TERM /THROUGH THURSDAY/...
As of 1010 PM: Shower and thunderstorm activity has ended across the
region and will send out an update shortly to reflect that. A few
isolated showers are possible until around midnight along remnant
outflow boundaries south of Charlotte. Latest RAP guidance shows
moisture convergence associated with weak northerly upslope flow in
the mountains and south of Charlotte. These areas along with the
Lakelands of the Upstate have the highest odds of patchy fog and
low clouds for tonight. Light northerly flow atop the region should
limit dense fog formation outside of the most protected mountain
valleys. Temperatures and dewpoints bottoming out in the upper 60s
to near 70 will make for another muggy August night.
The axis of the 500mb trough shifts slightly eastward for Thursday
afternoon; drier air will filter in above the PBL as a high
pressure center builds across the Mississippi Valley. With the
pattern still not having changed much, some low PoPs continue to
be warranted along and east of the Escarpment. Temps will trend
down slightly compared to today. The availability of the drier
air has two effects: it suggests greater potential for dewpoints
to mix out and further reduce the impact of heat index, but also
suggests any storms that do form will be more likely to generate a
severe microburst--though the risk still looks isolated. The risk
is not enough that SPC has noted us on the Day 2 outlook.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
As of 210 pm Wednesday: Surface trough will remain across the
forecast area through at least the first half of the short term,
delineating unseasonably low theta-e/PWAT air (over much of our
area) from a more tropical air mass (closer to the coast). As such,
fairly robust boundary layer mixing will result in surface dewpoints
falling off into ~the mid 60s across much of the area Friday
afternoon, and all but perhaps the extreme southeast zones are
expected to see little in the day of significant instability during
that time. As such, pops for diurnal convection are unseasonably
low, with 20% chances limited to the extreme southeast tier of the
forecast area.
By the end of the period, a strong Bermuda high is forecast to begin
showing signs of retrogression toward the Southeast Coast, allowing
for a moist southerly flow to become established across much of the
region, allowing for some degree of moisture return. The most
interesting aspect of the entire forecast revolves around the
potential for tropical/subtropical low development, which most major
model guidance depicts in some form or another, but with fairly wide
disagreement regarding timing/location/intensity. While this would
most likely impact our area (if it impacts our area at all) during
the medium range, some guidance sources suggest moisture from this
feature could impact the area as early as late in the short term. At
the very least, increasing low level moisture/instability supports
increasing pops to 20-30% across the forecast area for Saturday
afternoon. Temps are forecast to be right around normal through the
period.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 225 pm Wednesday: Eyes will be on the tropics (subtropics?)
for the medium range, with the latest 12Z run of the ECMWF being of
particular interest for our forecast area in bringing a tropical or
perhaps hybrid area of low pressure straight through the heart of
the western Carolinas Sunday through Sunday night. However, to say
that confidence in any one deterministic model solution is low at
this point would be quite the understatement. The latest GFS never
really achieves notable surface development, while the Canadian GEM
offers weak development that remains confined to the coast.
Regardless, pops will be on the increase through the period, as
southerly flow deepens west of rather strong Bermuda high. In terms
of the forecast, this will be manifest as pops for diurnal
convection creeping above climatology by Sunday afternoon,
continuing through the end of the forecast period. Temps are
generally forecast to remain near climo, although maxes could slide
a little below normal in light of increasing cloud cover.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
At KCLT and elsewhere: Moderate confidence in 00Z TAFs. An isolated
shower or thunderstorm can`t be completely ruled out at any TAF site
through 04Z including KCLT, mainly forming around remnant outflow
boundaries. Low clouds and patchy fog is likely for mountain valleys
tonight including KAVL, although light northerly flow across the
region should limit cigs/vsbys to IFR/LIFR or higher. There is a 10
percent chance of these conditions occurring at other locations
including KCLT. Any low cigs/vsbys should rapidly improve around 12Z.
Convection will be more isolated for Thursday with ridgetops,
foothills and I-77 corridor including KCLT having about a 40 percent
chance of shra or tsra sometime between 20Z and 00Z.
Outlook: The passing frontal boundary will remain stalled SE of the
area through Saturday, with lower end convective chances persisting.
Convective activity will likely be on the increase late this weekend
into early next week. Early fog/stratus will be possible each day
across mountain valleys.
Confidence Table...
02-08Z 08-14Z 14-20Z 20-00Z
KCLT High 100% High 89% High 100% High 100%
KGSP High 100% High 100% High 100% High 100%
KAVL High 90% Med 66% High 97% High 100%
KHKY High 100% High 95% High 100% High 100%
KGMU High 100% High 100% High 100% High 100%
KAND High 100% High 100% High 100% High 100%
The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:
www.weather.gov/gsp/aviation
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.
&&
$$
SYNOPSIS...JDL
NEAR TERM...Munroe/Wimberley
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...Munroe
Area Forecast Discussion
National Weather Service Newport/Morehead City NC
955 PM EDT Wed Aug 14 2019
.SYNOPSIS...
A cold front will slowly approach the area through Thursday
then dissipate over the region this weekend. High pressure
offshore will dominate early next week.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
As of 940 PM Wednesday...Showers and storms were most active
over southern and western portions of the CWA this evening and
continue at late evening over the Coastal Plains. Will leave
high chance PoPs in over these areas for the next few hours as
storms should gradually dissipate. HRRR and 3km NAM show
redevelopment of convection close to the coast early in the
morning and will continue to trend forecast in that direction
with high chance PoPs. No changes needed to forecast
temperatures as very warm and humid conditions persist with
continued above climo lows well into the 70s.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
As of 230 PM Wed...Area will remain in the moist warm sector
with front to the west, as weak shortwave energy continues to
move through the flow aloft. Expect isolated to scattered
showers and storms early, becoming scattered to numerous in the
afternoon and evening. Increased pops to likely for most of the
area with good agreement between guidance (NSSL-WRF, HREF and
HRRR). There is still a marginal severe threat, with damaging
winds possible, but main threat still looks likely locally heavy
rain with PWATS 2.25-2.5". Highs in the upper 80s to low 90s,
with heat index values around 100 deg.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
As of 230 AM Wed...A cold front will approach the area through
late week leading to unsettled weather. The front will
gradually dissipate over the region this weekend.
Fri through Tue...Better moisture begins to shift to cst late
in week into the weekend as the front sags into the area and
gradually dissipates. Will keep chc pops for the cst with mainly
slight chc inland thru Sunday. As offshore high pres becomes
dominant early next week expect wdly sct activity. With hgts
building a bit over the weekend into early next week and mdls
now not showing much E to NE wind raised temps a bit with highs
around 90 or low 90s inland with mid/upr 80s beaches most of the
period.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Short Term /through Thursday/...
As of 750 PM Wed...Largely VFR conditions this evening with the
exception of sites impacted by decaying showers and occasional
thunderstorms. Expect coverage to wane with loss of heating but
in the near term occasional sub-VFR conditions are possible at
all sites except PGV. Patchy fog and stratus are possible late
tonight into Thursday morning although with expected lingering
cloud cover confidence is lower than average. Some brief IFR is
possible. VFR returns by mid-morning with scattered showers and
thunderstorms expected again by the afternoon and evening with
brief sub-VFR conditions possible.
Long Term /Thursday night through Monday/...
As of 230 AM Wed...Deeper moisture begins to shift mainly E of
taf sites Fri into the weekend with less shra/tsra coverage and
mainly VFR. As usual some patchy fog/st poss early morn espcly
after most areas see decent rainfall.
&&
.MARINE...
Short Term /through Thursday/...
As of 955 PM Wednesday...Minimal changes needed to marine
forecast as SW winds continue at 10-20 knots with seas of 2-4
feet. The gradient relaxes a bit Thu with SW winds 10-15 kt.
Seas of 2-4 ft will persist through Thursday, but may see some 5
ft on the outer central and southern waters.
Long Term /Thursday night through Monday/...
As of 230 AM Wed...The weakening front tries to push into the
area Fri and Sat but looks like will dissipate with any post
frontal winds very light with dir grad becoming S/SE again later
Sat and SSW Sunday aob 15 kts. Seas mainly 2 to 4 ft thru
pd.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...MHX
NEAR TERM...CTC
SHORT TERM...CQD
LONG TERM...RF
AVIATION...RF/MS
MARINE...RF/CTC/CQD
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1106 PM CDT Wed Aug 14 2019
.UPDATE...For 06Z Aviation discussion below
&&
.SHORT TERM...(This evening through Thursday night)
Issued at 245 PM CDT Wed Aug 14 2019
Short term concerns remain convective trends into Thursday
afternoon/Thursday night.
Some heavier cumulus across southern MN with little in the way of
any radar returns associated. HRRR is gradually backing away at
its isolated shower threat late this afternoon. Will leave the
area dry overnight. Models indicate we will keep some form of mid
cloud deck across the CWA during the night associated with the
incoming weak short wave over southern Manitoba Canada at this
time. This may this may limit overall extent of fog formation.
Also, some drier air did work into the eastern CWA during the day
and will likely limit overall fog threat as well. We did keep
patchy wording for now.
Deterministic models diverge some on timing of next short wave
trough, with the ECMWF most consistent on moving it into eastern
Dakotas later Thursday afternoon. Expect some sunshine will warm
temepratures through the upper 70s most areas to the east by
Thursday afternoon. We continued to ramp up PoPs to likely over
west central by 00z Fri. Does look like forcing will be strong
enough and instability great enough for at least a small threat of
severe weather into the evening over western MN. 12z HREF drive
some hail/wind potential into west central MN. Will bring likely
PoP east into eastern MN as the upper trough moves through 06z-09z
Fri. It appears overall instability wanes overnight.
.LONG TERM...(Friday through Wednesday)
Issued at 245 PM CDT Wed Aug 14 2019
With the long term period beginning on Friday morning, overnight
precipitation should be exiting to our east. After that, we will
have one main chance of potentially widespread precipitation on
Saturday evening. The remainder of the period looks to be mostly
dry, with a warming trend for the middle of next week.
There are still timing differences with pushing the Thursday
night/early Friday shortwave east of our area, so we still carry
chance pops in eastern MN and western WI as that wave departs
Friday. Meanwhile, a strong low pressure system advancing eastward
across northern Saskatchewan and Manitoba will drag a trailing
cool front across the Dakotas Saturday and into Minnesota most
likely Saturday night. The strongest forcing will likely stay
north of our area, closer to the upper jet, and a separate
shortwave across Iowa will focus additional lift there. Still
expect showers and thunderstorms to move through along the front,
but with the strongest forcing to the north and south of us, it`s
uncertain at this point as to how widespread precipitation will
be locally. Mid level lapse rates are marginal and with MUCAPE
under 1,000 J/kg, severe weather chances are quite low. Individual
storms could produce temporary heavy rainfall, but overall the
flooding threat is also low.
High pressure will follow into early next week and push east of
our area by Tuesday. This will lead to southerly flow developing
and the western CONUS thermal ridge expanding eastward leading to
warming conditions by Wednesday and Thursday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1106 PM CDT Wed Aug 14 2019
Mid/high clouds will initially inhibit fog overnight, but
models/satellite indicate some scattering from the west so still
cannot rule out some patchy development. Expect an increase in
mid-level clouds on Thursday, especially during the afternoon.
Shower and thunderstorms look to spread eastward across the MN
portion of the area between 23Z Thursday and 06Z Friday. Light
and variable winds overnight become south-southwest on Thursday
morning ahead of the trough.
KMSP...There could be patchy fog around during the morning push,
but expect visibility at the site to remain VFR. Otherwise, increasing
low-end VFR clouds on Thursday afternoon with shra/ts chances
returning around/after 03Z Friday.
/OUTLOOK FOR KMSP/
Fri...VFR with MVFR/TSRA possible early. Wind S 5-10 kts.
Sat...VFR with MVFR/TSRA possible. Wind SW 10 kts.
Sun...VFR. Wind SW 10 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
&&
$$
SHORT TERM...DWE
LONG TERM...SPD
AVIATION...LS
Area Forecast Discussion
National Weather Service Marquette MI
731 PM EDT Wed Aug 14 2019
.SHORT TERM...(This evening through Thursday)
Issued at 411 PM EDT WED AUG 14 2019
WV imagery and RAP analysis indicated a low amplitude pattern with a
mid/uper level ridge over the southwest CONUS and a broad trough
from northeast Canada through the Great Lakes resulting in wnw flow
toward Upper Michigan. An upstream shortwave trough located over
southern Manitoba with limited moisture available supported mainly
an increase in mid/high clouds. Otherwise, with surface high
sprssure building across the northern Great Lakes, Vis loop showed
clear to partly cloud conditions with fair weather cu over inland
locations.
Tonight, favorable radiational cooling conditions during the early
overnight period should allow temps to again drop into the low to
mid 40s before mid clouds move in late and thicken ahead of the
shrtwv, especially over the west half. The clouds should also
limit potential for fog development.
Thursday, the shrtwv could bring some light showers or sprinkles
into the west early. However, expect a better chance for isold/sct
shra/tsra in the afternoon inland west, especially along lake
breeze boundaries, as daytime heating pushes MLCAPE values to near
500 J/Kg. With only marginal instability and 0-6km shear to
around 25 knots, no strong/svr storms are expected.
.LONG TERM...(Thursday night through Wednesday)
Issued at 307 PM EDT WED AUG 14 2019
The large-scale CONUS pattern continues to be one of southern U.S.
ridging and an active subtropical jet with multiple short waves on
its northern periphery keeping our weather locally unsettled at
least through the weekend.
The first chance of showers will be late tomorrow night over the far
west as a mid-level short wave approaches from the southwest.
Forcing with this wave will spread across the rest of Upper Michigan
during the day Friday, though ascent is not particularly strong. The
models struggle to destabilize beyond perhaps 1000 J/kg MLCAPE in
just a few pockets, again mainly west, so not too enthused about
thunderstorm chances on Friday, though there could be at least a few
rumbles. As the wave lifts off to the northeast Friday night,
heights rise briefly, though another subtle short wave quickly
approaches. Models shear it out enough that we don`t get any showers
from it, but it probably will be enough to keep clouds around early
Saturday.
The next big weather-maker will be a cold front approaching from the
northwest on Saturday. Still some timing uncertainty with the EC
slower than the American guidance. Right now, the timing isn`t
favorable for widespread thunderstorms with the front moving through
late Saturday night or early Sunday morning, though if the slower EC
verified there could be a window for storms on Sunday. Unfortunately
because of this timing uncertainty, had to carry shower and storm
chances for nearly all of Saturday and Sunday in this package. But
in reality there will likely be a decent dry period one of the two
days; stay tuned as we narrow that window down.
High pressure builds in behind the front and it looks like we`re dry
Monday through at least the middle of next week, except for maybe a
pesky shower or two over the west Tuesday night. Some of the models
try to reintroduce more summerlike temps by the end of the week, but
still plenty of time to watch that.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 730 PM EDT WED AUG 14 2019
VFR conditions continue through the forecast period, along with
winds less than 10 knots. Still some potential for ground fog in the
KIWD area later tonight but with mid clouds moving into that area
later this evening expect fog threat to be very limited and have
left out of the forecast at this time.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 411 PM EDT WED AUG 14 2019
Winds over the lake are expected to stay at or below 20 knots
through Saturday. Models are indicating the chance for an active
period of weather this upcoming weekend. Expect chances of showers
and thunderstorms through the weekend as well as the chance at gusty
conditions, up to 25 knots, Sunday morning through Sunday evening.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...RJC
AVIATION...RJT
MARINE...JLB
Area Forecast Discussion
National Weather Service Pueblo CO
259 PM MDT Wed Aug 14 2019
.SHORT TERM...(This evening through Thursday)
Issued at 238 PM MDT Wed Aug 14 2019
Some isolated showers/tstms will be possible into the early evening
over the mtns and high valleys, but the I-25 corridor and eastern
plains will be the main focus area for storms this evening as a weak
weather disturbance moves across the area. Isolated to scattered
storms are expected across portions of the I-25 corridor and plains,
with the are east plains likely see the best chances. The HRRR
shows only some isolated storms, The NAM Nest has a little more
coverage over the plains, with the potential for some strong storms
early in the evening over Otero and Bent Counties, and then after
about 7 pm, some strong storms moving into Kiowa and eastern Prowers
Counties. The earlier run of the NAM has showers/tstms continuing
over the far southeast plains into the late night hours, but the 18Z
run, as well as the lastest HRRR, shows activity ending by about
midnight or 1 AM. SPC still has the southeast plains outlooked for
the possibility of severe storms, with the main threats being large
hail and damaging wind gusts, but with shear values of 40+ kts
cannot rule out an isolated tornado.
On Thu a northerly surge moves through eastern CO by around midday,
and conditions look drier. Dew points this afternoon over the
southeast plains are in the 50s, but Thu afternoon they are expected
to drop into the 30s along the I-25 corridor, with some lingering
lower 50s over the eastern border area, while over the high country
dew points should be mostly in the 20s to lower 30s. There will
likely still be a be enough moisture and instability for a just a
few showers and tstms. Temps on Thu will be warmer across the
plains, with 90s for highs, with some locations along the Arkansas
River Valley see highs nearing 100. The San Luis Valley and the
Upper Arkansas River Valleys should see highs in the lower to mid
80s.
.LONG TERM...(Thursday night through Wednesday)
Issued at 238 PM MDT Wed Aug 14 2019
Flat westerly flow across the area will keep best mid level
moisture shunted fairly south of the region into the weekend,
before upper ridge amplifies over the Rockies early next week,
leading to a brief influx of deeper moisture Tue/Wed. Beginning
with Friday, low level moisture in place across the plains early
mixes eastward by late day, though perhaps just enough
instability/moisture linger for isolated afternoon/evening
convection along and east of the mountains. Best chance for a
stronger storm would be over the far east and up into nern CO,
where greater instability will reside. Sat will features a low
risk of some high based storms over the mountains and Palmer
Divide Sat as upper wave slides by to our north, while max temps
begin to creep back upward a few degf at many locations. Sun/Mon
look dry and hot, with only some very isolated weak convection
possible over the mountains Mon afternoon. Moisture returns
Tue/Wed under building high pressure aloft, with thunderstorm
chances increasing both days, especially across the mountains. Max
temps will remain warm, with lower Ark Valley again near 100f
both days.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 238 PM MDT Wed Aug 14 2019
Showers and thunderstorms will be possible thru early this evening
at KALS, KCOS and KPUB. If storms do move into the vicinity of a
terminal forecast site, the main threats will be gusty outflow winds
and lightning. Otherwise, VFR conditions are expected. Otherwise
VFR conditions are expected tonight and Thu. Chances for showers
and thunderstorms look lower on Thu.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...PETERSEN
AVIATION...28
AREA FORECAST DISCUSSION
National Weather Service Raleigh NC
932 PM EDT Wed Aug 14 2019
.SYNOPSIS...
A series of surface boundaries will likely stall and slowly
dissipate across central NC through late week. This will keep
unsettled and very humid conditions in place.
&&
.NEAR TERM /TONIGHT/...
As of 932 PM Wednesday...
The main cold front continued to weaken and remain well NW of our
region this evening. Therefore, much of NC continued in the very
humid air mass with surface dew points ranging in the lower 70s NW
into the upper 70s in the Coastal Plain. The depth of the moisture
was larger in the SE, where the 00Z/15 observed data indicated
Perceptible Water (PW) values near 2.25 inches across SE NC. These
readings tail off a bit to the NW, where readings were still 1.75
inches in the Triad region. Showers and thunderstorms have been more
isolated in the NW where the moisture depth is lower and convergence
has been lacking. In the east, showers and thunderstorms have been
generally scattered and associated with a weak trough over the
Piedmont, and along outflow/sea breeze boundaries that raced NW into
the Coastal Plain and southern part of NC. Several thunderstorms
have clustered in the vicinity of Johnston/northern Sampson/NW Wayne
and Wilson Counties where these boundaries were merging.
It appears that the showers and thunderstorms will be focused along
the merging boundaries over the eastern Sandhills, far SE Piedmont,
and Central Coastal Plain through around midnight. This is the
region where observational data including surface moisture
convergence, instability, and lift support the radar trends and CAM
forecasts support continued development until the instability is
worked over. Smithfield, Wilson, and areas NW of Goldsboro appear
likely to get locally heavy rain of 2+ inches. Additional widely
scattered showers/storms may develop near the boundaries in the next
few hours, mainly extending from near Southern Pines to Raleigh and
Rocky Mount. Otherwise, little if any additional showers are
expected.
Some stratus/fog appears likely late tonight given the nearly
saturated air mass. Lows hold above 70 to the mid 70s.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
As of 440 PM Wednesday...
A complex forecast continues in the short term as a low
amplitude trough axis remains centered over the Ohio Valley.
This morning at 500 mb a potent shortwave was analyzed back in
Oklahoma. This wave is forecast to continue to push southeast
and round the base of the trough. The wave will then push over
North Carolina Thursday afternoon. A significant amount of model
discrepancy exists here as the RAP holds the wave somewhat
together while the GFS shears it apart. One thing that is rather
consistent though is an upper level jet will strengthen across
the North Carolina Mountains. As this occurs central North
Carolina will be placed in a RRQ with upper level divergence
increasing. This working in tandem with the approaching
shortwave will provide more than sufficient lift. ML CAPE values
are again being advertised around 2000 J/kg with SFC to 6 km
shear forecast around 30 kts. PWATs are forecast to be around
1.75". Given the more than sufficient PWATs, instability, and
lift showers and thunderstorms appear likely. Shear values which
are around 30 kts would support some multi- cell clustering.
SPC has central/eastern North Carolina in a marginal risk to
account for this. Damaging wind gusts will be the primary
threat. High temperatures Thursday will be near normal, or
around 90 degrees.
Thursday night a cold front will approach from the west with the
upper level jet located over central North Carolina. Lower PWAT
air will slowly filter into the northwest Piedmont before the
front stalls across central North Carolina.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
As of 240 PM Wednesday...
Fri/Fri night: The surface boundary extending through the E Piedmont
early Fri is expected to drift back NW into the Foothills, propelled
in part by the westward-expanding Atlantic ridge. A very subtle
shear axis will hold over the coastal Carolinas, and forecast
soundings depict a fairly dry column west of this feature, including
western and much of central NC, with PW under 1.5" NW of the
Triangle. Will maintain the general flavor of the current forecast
with chance pops SE of Highway 1 and low to no pops to the west,
peaking in the afternoon followed by diminishing pops after
nightfall. High PW down east and meandering cell movement within
weak steering flow may result in pockets of high rainfall totals
there. Highs around 90 to the lower 90s, followed by lows of 69-76
with areas of fog/stratus likely to develop, mainly E, overnight.
Sat through Wed: A humid pattern with above-climo pops is expected
this weekend into early next week, as the main band of westerlies
holds well to our N. A weak mid level trough axis will hold to our
W, as Atlantic ridging attempts to build westward over the Southeast
coast through the period. A stream of high PW (over 2") sets up
through central NC, propelled inland from the coast over the weekend
with the building offshore ridge. Will carry good shower/storm
chances, focused during (but not limited to) the afternoon and
evening/early overnight hours. The greatest chance may occur this
weekend, as an 850 mb low located over E GA Sat afternoon tracks NE
through the Carolinas, bringing the potential for a shot of enhanced
low level moisture flux Sat night through Sun, and will show an
uptick in pops, mainly E, during this time. There is a band of
comparatively drier air, now noted on the west side of the Atlantic
ridge on GOES channel 9 WV imagery, that the models show swinging W
then NW, perhaps brushing through Eastern NC late Mon night through
Tue, which may lead to a relative lull in pops during this time
frame, providing a glimmer of dry hope within what should otherwise
be a muggy pattern with at least some pop every day, along with a
nearly daily risk of early-morning stratus/fog. Low level
thicknesses trend from slightly above normal over the weekend into
Mon to near normal Tue. Expect both highs and lows to edge a bit
warmer than usual. -GIH
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
As of 805 PM Wednesday...
Scattered showers and storms will dissipate in roughly the region
bounded by RDU, FAY, and RWI during the next few hours, where
outflow boundaries are about to merge there. Otherwise, areas of
low stratus and fog (IFR-MVFR) are expected to develop late tonight-
early Thu, with the associated moist layer expected to yield
occasional MVFR ceilings as it is heated and lifted into VFR range
by early Thu afternoon. Scattered convection will develop/occur
within a convergence zone provided by an Appalachian lee trough/old
front over cntl NC Thu aft-eve, but with a pulse-type/random nature
that yields low predictability of precise timing and location until
just a few hours prior to occurrence.
Outlook: Areas of stratus and fog are likely to develop again Thu
night, followed by patchier coverage each morning through the
weekend. A climatological chance of diurnal, pulse-type storms will
also exist through the weekend.
&&
.EQUIPMENT...
Twice daily upper air flights from GSO are scheduled through 12Z
Fri/16th.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Badgett/Haines
NEAR TERM...Badgett/Haines
SHORT TERM...Haines
LONG TERM...Hartfield
AVIATION...Haines
EQUIPMENT...RAH
Area Forecast Discussion
National Weather Service Tucson AZ
803 PM MST Wed Aug 14 2019
.SYNOPSIS...Excessive heat will remain as the primary concern for
Thursday and Friday. A small increase of moisture will promote
additional thunderstorm activity for the next few days but will
remain relatively subdued due to a poor monsoon pattern.
&&
.DISCUSSION...It was a quiet afternoon today with the high
pressure overhead inhibiting convective development. There was a
small moisture intrusion from the southeast that allowed for
isolated thunderstorms to develop, mainly over mountains south and
east of Tucson. The dewpoint struggled to reach 40 for Tucson
midday and 00Z sounding only had a PW value of 0.79. The main
story was the max temperature of 107 which tied the record set for
this day. Its unusual to have these high temperatures in August
and tomorrow will be even hotter for a forecast of 109 which will
be just under the record of 110. As such, an excessive heat
warning is in effect for Tucson until Thursday evening and for
other lower desert areas until Friday.
GFS and ECMWF show a splitting high overhead which is depressing
convective activity. A weak southeasterly flow in the mid levels
allow for some moisture transport from Sonora to support
convection Thursday afternoon. Storm development will likely
remain mountain bound to the south and east of Tucson and over the
White Mountains. UA WRFNAM is probably the most excited for
convection, but other HiRes models concur with the lack of
activity. As the highs split, the mean flow becomes more westerly
on Friday preventing moisture from aiding convection for the rest
of the weekend.
The mean flow will slowly starting shifting southeasterly and then
easterly early next week as the high slowly migrates back to the
four corners area. This should allow for a small uptick in
thunderstorm activity compared to the weekend. However, it will
remain relatively weak for this time of year. Higher temperatures
will return as the high rebuilds over AZ.
&&
.AVIATION...Valid through 16/06Z
SKC-FEW to the west and north of KTUS. SCT-BKN at 25k ft MSL
mainly to the east which inlcude KOLS/KDUG. Winds generally remain
under 10 kts. Isolated TSRA/SHRA expected Thursday afternoon and
evening, mainly near mountains, but within vicinity of KOLS/KDUG.
Aviation discussion not updated for TAF amendments.
&&
.FIRE WEATHER...
Dry and hot conditions are expected across most of southeast Arizona
through Friday with only slightly cooler conditions into the
weekend. Moisture will then begin to increase across eastern areas
later Thursday, with isolated to perhaps scattered showers and
thunderstorms primarily from Tucson east and south Thursday through
the upcoming weekend. Aside from gusty thunderstorm outflow winds,
wind speeds remain light and terrain driven through the weekend.
Minimum Relative Humidity values will be in the 10-20 percent range
in the valley locations through Friday, with only a modest increase
in values over the weekend, before likely dipping back into the
teens by next week.
&&
.PREV DISCUSSION... /issued 259 PM MST Wed Aug 14 2019/
Heat with a low-grade monsoon pattern into next week. Strong high
pressure overhead today and tomorrow for near record heat across
Southeast Arizona; especially from Tucson into the lower deserts.
We`re still pretty dry today with surface dew points in the upper
30s to lower 40s across the area and precipitable water values
around 60 percent of normal at about 1 inch (plus or minus a
tenth). As you might expect, much deeper moisture in central
Sonora southward along the Sierra Madres and west coast of Mexico.
A weak and shallow surge is working up the Gulf of California,
and the HRRR continues to advertise a strong outflow pushing into
our area from northern Sonora convection this evening. That should
give us enough moisture for a few more storms Thursday and Friday
afternoons.
As high pressure continues to spread westward and buckle a bit,
our flow will weaken and then gain a westerly component at most
levels by late Friday. This will tend to limit additional
significant moisture gains and keep our thunderstorm coverage
rather pedestrian with below average activity for mid August.
Ensembles and ensemble means continue to show good support for
strong high pressure rebuilding over Arizona and New Mexico the
first half of next week. We will probably end up with another
bout of excessive heat by next Tuesday and Wednesday. We may have
enough moisture around to help moderate that a couple of degrees,
and if the high center reconsolidates in a more favorable position
to bring back southerly and/or easterly flow we should manage a
few more storms (hopefully around next Wednesday or so).
&&
.CLIMATE...Near to record highs today and Thursday and possibly on
Friday. Below are forecast high temperatures and the record high
for today August 14th and tomorrow August 15th for select
locations across southeast Arizona.
DATE Aug 14 Aug 15
Fcst Rcd/Year Fcst Rcd/Year
Tucson Intl Airport 107 107/2015 109 110/2015
Bisbee-Douglas Airport 100 100/2010 97 101/2015
Ajo 111 113/2012 113 113/2015
Kitt Peak 89 88/1962 90 87/1962
Organ Pipe Cactus 111 112/2015 112 112/2015
Picacho Peak 111 110/2015 111 111/2015
Safford Ag Station 105 105/2015 105 106/2015
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
Excessive Heat Warning until 8 PM MST Thursday for AZZ504-506-
509.
Excessive Heat Warning until 7 PM MST Friday for AZZ501-502-505.
&&
$$
Pawlak
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