Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 06/21/17
Area Forecast Discussion...UPDATED
National Weather Service Albuquerque NM
547 PM MDT Tue Jun 20 2017
.AVIATION...
00Z TAF CYCLE
North to northwest flow aloft over New Mexico on east side of Four
Corners high centered over east-central AZ and west-central NM.
Isold tstms will continue until around 20/04Z across the southwest
mountains and eastern plains. A few of the storms will contain brief
MVFR cigs/vsbys obscg mt tops and wind gusts to around 45kt as well
as hail. Potential for lcl MVFR cigs over the eastern plains aft
08Z. Storms will be mainly confined to the central mtn chain ewd
Wednesday as dry air filters into southwest NM.
33
&&
.PREV DISCUSSION...335 PM MDT Tue Jun 20 2017...
.SYNOPSIS...
Very hot temperatures will persist through at least Thursday across
the Land of Enchantment. A few storms will be possible each afternoon
and evening, which may produce gusty winds and small hail. Some
relief to the heat is expected on Friday, mainly across eastern New
Mexico as a cold front slides through the plains and westward into
the Rio Grande Valley. Moisture associated with the front will
enhance thunderstorm chances Friday through at least the weekend. The
thunderstorm activity should keep the triple digit heat at bay for
at least through the first half of next week.
&&
.DISCUSSION...
Hot temperatures will remain the rule for the next few days as a
597dam high parks over the AZ/NM border. Dewpoints were up in the
50s this morning here at ABQ, but have since dropped to 17 with 5%
RH. This has been the case across much of the RGV and points
westward to the ContDvd, which allowed temperatures to soar.
Temperatures will near records across much of central and western NM
through at least Thursday, if not Friday. Will expand the Heat
Advisory on Wednesday to include Espanola. Will also add in Thursday
for the same areas, plus Socorro.
As for storms, an axis of instability exists from the SW mtns across
NE NM this afternoon, with the strongest instability across Union
Co. per the LAPS analysis. Could see a few more strong or severe
storms in this area through the evening, with hail and gusty
downburst winds the main threats. Most models show a little complex
of storms lasting well into the evening across the northeast, but
should diminish by midnight. Wednesday should be similar to today,
with the northeast being favored for storms in the aftn and eve
again. Less storms are expected on Thursday, therefore, Thursday
should be the hottest day of this stretch.
On Friday, the upper high sinks southward as a trough crosses the
northern Rockies. An associated back door cold front is expected
to slide down the plains, and models are showing the front sliding
through much faster than they were this time yesterday. Both the 12Z
GFS and the 18Z NAM have the front completely through the plains by
18Z Fri, and pushing through the gaps of the central mountain in the
afternoon. As a result, have lowered temps a few degrees across the
east on Friday, particularly NE, but western areas will remain hot.
The RGV will depend on just how fast and strong the front pushes into
the area. The ECMWF remains much slower with the front, not bringing
it down the plains until Saturday. Gusty winds can be expected along
and behind the front.
Low level moisture will be replenished behind the front which will
likely enhanced thunderstorm chances Friday through the weekend with
northwest flow aloft. Not out of the question to see a few strong or
severe storms in this pattern, but shouldn`t see triple digit heat.
34
&&
.FIRE WEATHER...
...NEAR RECORD TO RECORD HEAT THROUGH THURSDAY AND POSSIBLY INTO
FRIDAY...
The upper high over New Mexico will continue to dominate through
Thursday and into Friday but with some not so subtle changes
starting to show up in the forecast models later this week. In the
meantime, increasing instability with high Haines and some areas of
Super Haines as well as near record to record heat and overall
drying will become more widespread Wednesday and Thursday. Moisture
trapped under the upper high will recycle for thunderstorms to
develop Wednesday and Thursday over the higher terrain then drift
into the valleys and plains, although the areal coverage and chances
for wetting rain will be at a minimum Thursday. Much of any wetting
rain may be relatively localized with many of the cells be more
likely to produce gusty variable winds rather than much rain.
For tonight, cell motion will be slow and somewhat erratic with
storms drifting off the Sangre de Cristo mts and into the highlands
and northeast plains. Farther south and west, motion will be the
most variable. The NAM12 indicates a complex of storms dropping into
ne NM later this afternoon/evening, creating a line of gusty
north/northeast winds which pushes into the east central and along
the east slopes of the central mt chain. This makes for difficult
timing of any east wind into the RGV this evening/tonight. Both RAP
and HRRR not nearly as aggressive with the thunderstorms over the
east and therefore the surface gradient tonight.
Northwest flow looks to strengthen some Wednesday and moreso
Thursday/Friday as the upper high center retreats southward. The
northern tier of zones, 101-102 and 103, may be most impacted by
increasing winds/dryness as the theta-e axis shifts to the east and
south. In fact, portions of the northwest plateau may see several
hours of critical conditions combined with super Haines Thursday
afternoon.
Overnight humidity recoveries continue to be mostly good central and
east tonight through Wednesday night with fair to locally poor
recoveries west. Thursday night will be drier especially for the
west and central where poor recoveries will be widespread after
largely single digit humidities Thursday afternoon.
Higher mixing heights Wednesday and Thursday lead to good to
excellent vent rates over the majority of the forecast areas.
Some of the forecast models are indicating the anticipated heat
relieving front may be faster, and could reach ne NM as early as
Friday morning then push into the RGV late Friday afternoon/early
evening. Confidence isn`t the greatest due to the timing differences
but the forecast is leaning towards a faster movement. While single
digit humidities persist central and west Friday with some areas of
Super Haines, the east will see improvement, and both min and max
humidities trend upward over the weekend as high temperatures cool
to near normal and below overall by Sunday. Chances for convection
with wetting rain increase as well over the east, central and
southwest. For next week, the drier westerly flow is nowhere in
sight, models now indicate what looks suspiciously like a monsoon
pattern for the middle of next week. Maybe picking up on climo.
&&
.AVIATION...
18Z TAF CYCLE
Upper high center over west central NM. Isold to sct tstms to develop
over the higher terrain aft 18Z and drift into the valleys and
plains. A few of the storms may contain brief MVFR cigs/vsbys obscg
mt tops and wind gusts to around 45kt as well as small hail.
Potential for lcl MVFR cigs over the eastern plains aft 08Z.
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM MDT this evening for the following zones...
NMZ501>509-519.
Heat Advisory from 2 PM to 7 PM MDT Wednesday for the following
zones... NMZ501>509-517-519.
Heat Advisory from 2 PM to 7 PM MDT Thursday for the following
zones... NMZ501>509-517-519-520.
&&
$$
34
Area Forecast Discussion
National Weather Service Albany NY
1103 PM EDT Tue Jun 20 2017
.SYNOPSIS...
An upper level disturbance will bring isolated to
scattered showers mainly north and west of the Capital Region late
tonight. Seasonable and comfortable weather is expected tomorrow
into Thursday before warmer and more humid conditions return for
Friday, along with a chance for showers and thunderstorms.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 11 PM EDT...A short-wave continues to move across the
forecast area, as a few isolated showers continue across the
Mohawk and Schoharie Valleys, as well as the Capital Region.
The sky cover was tapered to partly cloudy or mostly clear prior
to midnight, but another short-wave in the water vapor imagery
moving across the central/eastern Great Lakes Region and Lake
Huron is approaching western NY with the clouds increasing again.
Scattered showers with an isolated rumble of thunder is moving
across southeast Ontario and the eastern Great Lakes Region
towards the Niagara frontier of the western NY. We trended the
showers into the western Adirondacks and west-central Mohawk
Valley after midnight. The instability looks weak with less than
250 J/kg, we placed a slight chc of thunder in for the western
Dacks/western Mohawk Valley. We also tried to follow the last
3-km HRRR trends for the short- wave associated with the upper
trough axis approaching early WED morning. Overnight lows will
generally be in the mid 50s to low 60s.
On Wednesday, the upper level trough axis will shift across the
Northeast. There still may be a few isolated showers (perhaps a
rumble of thunder too) across far northern areas, although coverage
will likely be slightly less than today, with the best chance in.
the late morning through mid afternoon hours. In addition, the
threat for showers will start to decrease by later in the afternoon
hours, as the better forcing starts to shift east of the region, as
the upper level shortwave starts to depart.
Otherwise, skies will be partly sunny and good mixing is expected
once again thanks to the cooler temps aloft overhead. Some westerly
wind gusts may once again exceed 20 mph during the afternoon hours
with comfortable dewpoint levels in the 50s. High temps should
reach the mid to upper 70s for valley areas (perhaps near 80 around
Poughkeepsie) with upper 60s to low 70s across the hills and
mountains.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
A dry period of weather is expected Wednesday night through
Thursday as a ridge of high pressure settles across our region.
Lows Wednesday night are expected to be in the upper 40s to
upper 50s with highs on Thursday in the upper 60s to lower 80s.
However, another piece of upper energy begins to approach
Thursday night with increasing warm advection and moisture.
Scattered showers are once again possible Thursday night with
the forcing and moisture advection associated with the
increasing warm advection. Lows Thursday night in the upper 50s
to mid 60s.
Friday is expected to be unsettled with our area in a warm
sector ahead of a cold front approaching from the Great Lakes
with a zonal, southwest flow aloft. Guidance indicating a pre-
frontal surface trough moving into our area during the
afternoon, which would likely trigger showers and thunderstorms.
Will have to watch for the potential for strong storms due to
moderate instability and vertical wind shear. Highs on Friday
are expected to be in the mid 70s to mid 80s.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
The first part of the extended will be wet as we see a cold front
pass through Friday night...setting off showers and possible
thunderstorms. This will be followed by a mostly dry weekend as a
second cold front over extreme southeast Ontario succumbs to
gradually building high pressure originating over the Rockies. This
broad area will be centered over the mid-south Tuesday. In the
meantime, a developing wave along the cold front that passes through
at the end of this work week will provide at least a chance of
showers again for Sunday night and Monday, but this should be less
substantial than Friday`s precipitation.
Generally, day-to-day high temperatures will run the same or cooler,
with upper 60s to lower 80s readings on Saturday becoming around 60
degrees to mid 70s highs by Tuesday. Lows will follow a similar
pattern...with upper 50s to upper 60s readings Friday night becoming
upper 40s to mid 50s by Monday night.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions are expected at the TAF sites for the entire TAF
period ending at 00Z Thursday. A nearby upper level trough may
allow for a few brief rain showers early this evening especially
near the Mohawk Valley and Capital Region, but
coverage/duration is fairly limited should wane with the loss of
the diurnal heating. Further south, it looks to stay dry. All
sites should have sct-bkn cigs at 5-7 kft early on, but will
become few-sct shortly before or just after midnight. The winds
will start to diminish this evening with the loss of daytime
heating with the highest winds expected to stay under 10 kts.
There will be just some few-sct high cirrus clouds overnight.
During the day on Wednesday, an upper level trough will be
located over the area. Daytime heating will allow for a few
more clouds and the wind to pick up once again. Any isolated
showers on Wednesday should remain mainly west or north of the
TAF sites. West winds will increase to about 10 kts with some
sct-bkn stratocu around 6 kft and some passing mid-level clouds
as well.
Outlook...
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: No Operational Impact. NO SIG WX.
Thursday Night: Moderate Operational Impact. Chance of SHRA.
Friday: High Operational Impact. Likely SHRA...TSRA.
Friday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Saturday: Low Operational Impact. Slight Chance of SHRA.
Saturday Night: No Operational Impact. NO SIG WX.
Sunday: Low Operational Impact. Slight Chance of SHRA.
&&
.FIRE WEATHER...
Winds may gust to 25 mph Wednesday afternoon...
Seasonable and comfortable weather is expected tomorrow
into Thursday before warmer and more humid conditions return for
Friday, along with a chance for showers and thunderstorms.
Relative humidity values will recover to 75 to 100 percent
tonight, drop to 40 to 60 percent Wednesday afternoon, recover
to 75 to 100 percent Wednesday night, and drop to 35 to 60
percent Thursday afternoon.
Winds will be southwest winds at 5 to 10 mph tonight, west at 10
to 15 mph with gusts to 25 mph Wednesday, and west at 5 to 10
mph Wednesday night and Thursday.
&&
.HYDROLOGY...
Scattered showers and isolated thunderstorms are in the
forecast for Wednesday with more widespread showers and
thunderstorms Friday after a dry day on Thursday.
At this time most areas through Friday will have QPF values
between 0.10 and 0.50 inch. Heavier rain may fall on Friday
especially if some thunderstorms train over the same area.
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.
&&
.EQUIPMENT...
KGFL airport observation continues to experience intermittent
communication issues.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...Frugis/11/Wasula
NEAR TERM...Frugis/Wasula
SHORT TERM...11/NAS
LONG TERM...ELH
AVIATION...Frugis/11/Wasula
FIRE WEATHER...11/NAS
HYDROLOGY...11/NAS
EQUIPMENT...
Area Forecast Discussion
National Weather Service La Crosse WI
638 PM CDT Tue Jun 20 2017
.SHORT TERM...(Tonight through Wednesday Night)
Issued at 143 PM CDT Tue Jun 20 2017
Current water vapor imagery coupled with RAP 500mb analysis shows
the shortwave trough that gave the area morning convection now
sliding southeast toward Lake Michigan. High pressure now building
into our forecast area from the Dakotas/southern Canada. This high
will slide southeast across the area overnight for partly cloudy
skies. Given the rainfall that occurred today/moist ground, and
mostly clear skies/light winds tonight, should see areas of fog,
mainly over central WI where the ridge axis/lightest winds will
reside longest. Farther west, along and west of the Mississippi
River, there will be an increase in warm air advection mid-cloud
which should inhibit radiational cooling/fog formation. Otherwise,
looking for lows in the middle 40s in the Sand Country of central
WI, to the lower/middle 50s elsewhere.
For Wednesday, low pressure crossing the Dakotas will bring a push
of warm air advection and moisture transport into the area by
afternoon for a chance of elevated shower/thunderstorm activity.
Highest chances look to be along/west of the Mississippi River where
stronger push of moisture transport will exist. Otherwise, look for
highs in the middle 70s to around 80.
Showers and thunderstorms will become likely Wednesday night as
moisture transport increases ahead/along of a cold front pushing
into the area from MN. NAM/GFS showing 0-3km MUCAPE generally in the
1500-2000j/kg range with bulk shear values in the 25-40kt range.
Bufkit soundings showing this convection would be mainly elevated in
nature with LFCs generally above 800mb. At the same time, NAM is
pushing precipitable water values into the 1.5 to 1.7 inch range.
So, looking like a chance for a few strong to possibly severe storms
with hail, heavy rainfall being the main threats.
.LONG TERM...(Thursday through Tuesday)
Issued at 143 PM CDT Tue Jun 20 2017
The aforementioned cold front pushing into the area Wednesday night
looks to lay up across far southern WI/northern IL/IA by Thursday
afternoon as it becomes parallel to the mid-level flow. Increasing
moisture transport and lift over the front along with a fairly
strong mid-level frontogenetic feature will produce the likelihood
of showers/thunderstorms across our area. NAM/GFS showing MUCAPE
increasing into the 2000-4000j/kg range by afternoon mainly
along/south of I-90 with NAM displaying a whopping 50-60kt of Bulk
Shear in the 0-3km layer. Taking a look at Bufkit soundings shows
most of the thunderstorms over our area will have elevated LFCs
north of the front for a large hail threat with the more surface-
based storms/tornado threat across IL into IA. Of course, final
outcome will be the exact position of the front which is still yet
to be determined. In addition, with precipitable water values pumped
up into the 1.7-2.0 inch range, these storms will be efficient heavy
rain-makers. Will therefore have to keep a vigilant eye on the
evolution of this scenario for severe potential.
A longwave trough digs over the region for Friday through Tuesday.
Shortwave troughs embedded within this cyclonic flow and steeper
lapse rates will trigger daytime cumulus and the possibility of a few
showers/isolated thunderstorms from time to time. Otherwise, look
for cooler temperatures, especially on Saturday and Sunday with
highs only expected to be in the 60s/lower 70s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 638 PM CDT Tue Jun 20 2017
The NAM develops some fog at KLSE late tonight. However both the
GFS and RAP keep the boundary layer dry. With the diurnal mixing
that took place on Tuesday afternoon, thinking that the RAP and
GFS solutions seem more realistic, so went with them.
A short wave trough will bring a broken mid to high deck of clouds
to the area late tonight and Wednesday morning as it moves
southeast through Iowa. A 6 to 8K deck of diurnal clouds will
develop on Wednesday afternoon. There is a a chance of showers and
storms on Wednesday afternoon, but confidence was not high to
include them at this time.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...Boyne
Area Forecast Discussion
National Weather Service Bismarck ND
954 PM CDT Tue Jun 20 2017
.UPDATE...
Issued at 952 PM CDT Tue Jun 20 2017
Current POP trends too fast especially northwest into the
central for this evening. Cut back for the evening until early
morning. Otherwise current forecast ok.
UPDATE Issued at 623 PM CDT Tue Jun 20 2017
Trimmed the early evening POPs back based on current CAM models
and satellite and radar trends. Will see more showers and
scattered thunderstorms develop as upstream shortwave and low to
mid level warm advection develop around or after midnight.
Otherwise current forecast looks good.
&&
.SHORT TERM...(This evening through Wednesday)
Issued at 256 PM CDT Tue Jun 20 2017
Highlights of the short term forecast period include isolated to
scattered showers and thunderstorms tonight and early Wednesday,
followed by a warm and breezy Wednesday afternoon.
As of 19 UTC, isolated and high-based showers continue moving to
the southeast and extend from about Watford City to New Salem and
Fort Yates. Despite a dry lower atmosphere as sampled by the 12
UTC Bismarck and Glasgow RAOBs, some precipitation is reaching the
ground per ASOS/AWOS observations and thus we have extended low-
end precipitation chances through late afternoon in south central
ND. Overall, the weak vorticity maximum embedded in northwesterly
flow aloft on the leading edge of 500 mb height rises that seems
to be driving this activity is forecast by recent RAP iterations
to shear southeast and weaken by 00 UTC.
Synoptically, a shortwave trough is expected to strengthen as it
rapidly moves from western British Columbia this evening and into
southern Manitoba by Thursday evening. A 35-45 kt southerly low-
level jet is forecast to develop in advance of that wave tonight,
and ascent based near 850 mb related to that wind maximum and the
associated warm air advection will likely be sufficient to yield
isolated to scattered showers and thunderstorms, mainly after 05
UTC and mainly from Minot to Jamestown per CAMs through the 18 UTC
HRRR and 15 UTC ESRL HRRR. Forecast soundings show steepening mid-
level lapse rates associated with an elevated mixed layer. We will
lack rich moisture and MUCAPE for parcels lifted from about 850 mb
will generally peak from 500 to 800 J/kg, so while a strong storm
or two is possible, the probability of severe weather appears low
at this time despite strengthening wind fields aloft.
A mid-level thermal ridge will cross the region Wednesday ahead of
a cold frontal passage that is expected during the afternoon. We
leaned on the warmer edge of of model temperature forecast output
for highs on Wednesday given expected deep mixing along and to the
west of the frontal zone, and in respect to recent model biases. A
low probability of convection will exist in the James River Valley
during the afternoon, but we are downplaying any risk of strong or
severe storms because we believe the prospects of deep convective
development are highest east of the area per the 12 UTC NAM, GFS,
and ECMWF simulations. The 09 UTC SREF calibrated severe storm
guidance is also very low in our area Wednesday. Behind the front,
northwest wind gusts to 30 mph are forecast with momentum transfer
via cold advection in a deep boundary layer. Low humidities near
20 percent will yield some elevation in fire concerns, but fuel
status may not yet support critical (red-flag type) designation.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 256 PM CDT Tue Jun 20 2017
Much cooler, below-normal temperatures are expected late this week
and into the weekend.
The 12 UTC global model suite continued to advertise a trough at
500 mb developing over the region by Friday and lingering through
the weekend. In general the last few GFS and ECMWF cycles have
been trending drier during this time period, with a tendency for
shortwaves embedded in the mean trough to be open waves instead of
closed with deeper dynamics as some earlier iterations suggested.
Thus, our forecast stayed the course with only a chance of showers
in this period. Instability per model-derived CAPE fields is low
and thus the probability for thunderstorms is low. Our confidence
remains high in highs only staying in the 60s F in many areas on
Friday and Saturday, before mid-level heights begin to rebound and
yield a warming trend again by early next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 623 PM CDT Tue Jun 20 2017
A warm front extended from low pressure in Alberta southeast
through eastern Montana. The warm front will be the focus for
scattered showers and thunderstorms tonight northwest around 06Z
moving into the central between 09-15Z. Otherwise VFR at all TAF
sites through the 00Z period.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...CJS
LONG TERM...CJS
AVIATION...WAA
Area Forecast Discussion
National Weather Service Cleveland OH
858 PM EDT Tue Jun 20 2017
.SYNOPSIS...
An upper level trough will gradually shift eastward across the
Great Lakes through tonight. High pressure will build east
across the area Wednesday and Wednesday night, with a warm
front lifting northward over the area by Thursday. The front
will push south on Friday reaching the Ohio valley by Friday
night.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Update...Adjustments made to sky, pop, and hourly temps taking
current conditions into expected trends based on the HRRR and
satellite based timing.
Original...Last piece of jet energy is currently diving through
the west side of an upper level trough that remains over the
central Great Lakes. Expect to see isolated/scattered
showers/thunderstorms move across the area this evening into the
early overnight.
Lows tonight will be similar to last night.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY NIGHT/...
Cold front looks as if it will be south of the area by late
morning with all the shower/thunderstorm chances sagging
southward with it. HIgh pressure will then increase its
influence on the region Wednesday afternoon into Wednesday
night. The frontal boundary will lift back to the north on
Thursday with chances for thunderstorms increasing through the
day. Better chances will be closer to Lake Erie. IT will be
warmer and more humid on Thursday highs back into the 80s. A
cold front will move into the central Great Lakes Thursday night
and then sweep across the region at some point Friday evening.
THunderstorms will become most numerous on Friday with some
strong to severe storms possible. Still some uncertainty on how
much impact cloud cover will have on the instability across the
region. Friday will be another humid day with highs once again
in the 80s.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
With only marginal moisture on Sat will stay with just small chc
pops for shra or maybe and isolated tsra. The next s/w trough
digging into the upper lakes will start to induce a surface low to
develop somewhere near lower MI Sat night into Sun. Moisture is
shown to pool over the area so will ramp up pops Sat night into Sun.
The low and associated cold front should be shifting ENE of the area
by Sun night so the threat for shra will taper off west to east.
High pressure should build NE into the area Mon and still dominate
on Tue. The high should try and provide dry wx Mon thru Tue but
there will be an upper level trough over the area so some isolated
convection could occur with daytime heating or off of lake erie late
at night or in the morning.
Near normal temps Sat into Sun will trend cooler by Mon then start
to moderate a few degrees warmer for Tue.
&&
.AVIATION /00Z Wednesday THROUGH Sunday/...
A trough across SERN WI will move SE across the area overnight.
A band of sct shra ahead of the trough will move across the
forecast area overnight. Can not rule out an isolated rumble of
thunder or two.
OUTLOOK...Low chance of non-VFR Wed thru Sun in shra/tsra
except good chance Fri into Fri night with passage of a cold
front.
&&
.MARINE...
West winds of 15 to 20 knots producing marginal SCA conditions for
the east part of the lake will diminish tonight as high pressure
starts to spread north into the lake. The high will provide
relatively light winds Wed that turn south by Thu then SW as the
high shifts off to the east.
A cold front should push SE across the lake later Fri into Fri night
veering winds to the NW for late Fri night and Sat. Winds get more
uncertain Sat night and Sun as a weak low may start to develop over
lower MI and track near the lake Sun.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Beach Hazards Statement until 9 PM EDT this evening for OHZ012-
089.
PA...Beach Hazards Statement until 9 PM EDT this evening for PAZ001.
MARINE...Small Craft Advisory until 9 PM EDT this evening for
LEZ147>149.
&&
$$
SYNOPSIS...Mullen
NEAR TERM...TK/Mullen
SHORT TERM...Mullen
LONG TERM...Adams
AVIATION...DJB
MARINE...Adams
Area Forecast Discussion
National Weather Service Cheyenne WY
618 PM MDT Tue Jun 20 2017
.UPDATE...
Issued at 617 PM MDT Tue Jun 20 2017
Convection continues to expand in coverage over the mountains and
high valleys, and even eastward toward I-25 where showers are
currently developing off a number of llvl boundaries. Expanded
PoPs accordingly. Do think a few hundredths of an inch of
rainfall will reach the sfc with a few of the storms, but will
continue to advertise gusty winds of 40 to 50 mph as well due to
the dry sub-cloud layer. HRRR seems to be capturing current
conditions pretty well, so increased PoPs slightly through tonight
even further east into the Panhandle as the shortwave moves
overhead.
UPDATE Issued at 354 PM MDT Tue Jun 20 2017
Quick update to add some isolated thunderstorms into western
Carbon County late this afternoon and early this evening based on
latest satellite and radar trends. Any storms should be high-based
and may not produce much in the way of precip but isolated
instances of gusty winds may occur with any of these showers or
storms due to the deep, dry sub-cloud layer.
&&
.SHORT TERM...(This evening through Thursday)
Issued at 150 PM MDT Tue Jun 20 2017
Weak shortwave energy will
track to our north tonight. The strong upper ridge currently in
place over the SW US will flatten somewhat on Thursday as a stronger
shortwave moves quickly eastward along the Canadian border. At the
surface, a weak trough/front will be located over western NE on
Wednesday trailing southwestward into CO. This trough will
weaken/wash out on Wednesday night as a second front drops south and
across the area early Thursday.
Wednesday will be another warm day and with the surface trough to
our east initially, westerly to northwesterly boundary layer winds
will limit moisture and thus chances for convection, especially with
the continued presence of warm and dry air aloft. Early on Wednesday
evening some isolated to widely scattered convection is possible
over the mountains and along/east of the Laramie Range as winds turn
more easterly and upslope.
Heights aloft fall slightly on Thursday as the above-mentioned
shortwave tracks to our north. In the post frontal environment on
Thursday afternoon, models show fairly rich boundary layer moisture
characterized by dewpoints in the upper 40s to low 50s returning
east of the Laramie Range in northeasterly to easterly upslope flow.
This moisture will be topped by steep lapse rates and moderately
fast westerly flow aloft providing favorable instability/shear
parameter space for the development of locally strong/severe
convection. Best chances for this will be along the Cheyenne Ridge
east of the Laramie Range where upslope flow should be able to be
maximized and any cap overcome. Large hail looks to be the primary
threat with this convection.
.LONG TERM...(Thursday night through Tuesday)
Issued at 150 PM MDT Tue Jun 20 2017
Thursday night:
A few strong to severe thunderstorms still looks like a good bet
mainly across the southern portions of Wyoming into the southern
Panhandle. The NAM/GFS still are showing some capping taking place
especially across the panhandle, but we are still concerned that
some storms may fire along the Laramie range and may be able to
push into the southern Panhandle Thursday evening despite the
capping potential.
Friday-Saturday:
Cooler and drier conditions are in store for the area on Friday
ahead of a much stronger cold front. This unseasonably strong
front is progged to push through the area Friday night. A strong
gradient is possible along this front, which may result in some
abrupt changes Friday night. Temperatures may tumble into the 40s
by midnight along with the potential for rain showers with even
some snow showers possible in elevations above 9000ft. On
Saturday,the ensembles are showing the surface high pressure
(1028mb) nosing its way south along the Laramie Range on Saturday.
In fact, the NAEFS ensembles are showing mean sea Level standard
deviations about 2 to 3mb higher than normal for this time of
year. This will most likely result in a very chilly morning on
Saturday with lows starting out in the upper 30s in the Laramie
Valley, and low to mid 40s east of the laramie Range. Meanwhile,
afternoon highs may struggle to reach the 60s depending on how
long the rain and cloud cover hangs on.
Sunday-Tuesday:
Temperatures should begin to moderate during this period as the
upper level ridge slows builds into the area. In addition, drier
conditions should be in store early next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 617 PM MDT Tue Jun 20 2017
Showers and thunderstorms will occur over portions of southeast
Wyoming this evening, with a few showers potentially spreading
east into the northern Nebraska Panhandle tonight. Impacts will be
focused on gusty and erratic winds for any storms that move over
the terminals. Otherwise, VFR conditions will prevail with
widespread breezy northwest winds expected on Wednesday.
&&
.FIRE WEATHER...
Issued at 150 PM MDT Tue Jun 20 2017
Warm and occasionally breezy conditions will occur
each afternoon through Thursday to the west of the Laramie Range.
Fuels remain relatively green though which preclude much of a fire
weather concern. Much cooler temperatures and some chances of
showers/rain are on tap for Friday into Saturday.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
UPDATE...RJM
SHORT TERM...DEL
LONG TERM...REC
AVIATION...RJM
FIRE WEATHER...DEL
Area Forecast Discussion
National Weather Service Dodge City KS
605 PM CDT Tue Jun 20 2017
...UPDATE TO AVIATION...
.SHORT TERM...(This evening through Wednesday)
Issued at 151 PM CDT Tue Jun 20 2017
Afternoon CU developing along a surface boundary that extended
from extreme southeast Colorado to north central Kansas earlier
this afternoon. East of this boundary a southerly wind and surface
dew points in the mid to upper 60s. Based on 18z verification it
appears that the HRRR may have the right idea with the better
chance for convection developing later today a along surface
boundary in west central and north central Kansas. At this time
the area most favorable to late day convection will be across
north central Kansas given that it will be just east of the 700mb
temperature gradient. 0-6km shear and mid level instability late
today and early tonight suggests that any storm that does develop
in these areas has the potential to become severe with the primary
threat early in the event being 2 to 3 inch hail and strong
damaging winds in excess of 60 mph.
Once developed these storms are expected to move south across
western Kansas early this evening. Still some question how long
these storms will last early tonight but given the latest HRRR and
18z NAM the potential exists that these storms may hold together
as they move all the way south to near the Oklahoma border based
on the low level moisture axis and 25 to 35 knot 0-1km south
winds. Will therefore keep a mention of ongoing convection through
midnight for much of western Kansas. This evening the hail threat
will decrease as these storms move south but strong winds and
heavy rainfall will still be possible from some of these storms
early tonight.
On Wednesday 850mb temperatures warm into the upper 20s to lower
30s which suggests highs will climb into the upper 90s to around
100 degrees for all of western Kansas. By late day there will once
again be a chance for some scattered strong to severe
thunderstorms along a surface boundary which is forecast to be
located once again near the Colorado border. Convection that does
develop along this boundary late Thursday will move southeast
again across western Kansas and is expected to weaken through the
evening. The GFS does hint at a weak upper wave crossing southwest
Kansas early Wednesday night which if this does occur may enhance
convection and keep some night time storms going through at least
midnight for locations west of highway 283.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 151 PM CDT Tue Jun 20 2017
On Thursday the surface boundary/dry line will again be located
from extreme southeast Colorado to northwest Kansas. 850mb
temperatures at 00z Friday are forecast to be at or only a degree
or two warmer compared to 00z Thursday. Highs once again around
100 degrees still look on track for western Kansas along with a
chance for late day severe thunderstorms.
Thunderstorm chances for western Kansas currently appears more
favorable Thursday night as an upper level trough exits the
central Rockies and crosses the West Central High Plains.
Confidence is not high on how organized this convection will be as
it crosses Western Kansas Thursday night but at this time this
may be the better opportunity for widespread precipitation.
Periods of heavy rainfall and gusty winds will be the main hazard
should an organized complex of storms roll across western Kansas
Thursday night.
A stronger upper level trough will cross the plains on Friday and
as it does a surface cold front will move across western Kansas.
This will not only bring another chance for thunderstorms on
Friday but also some cooler air is expected to return. Models over
the weekend disagree on how much cooling will occur behind this
front and how far this front will move before stalling out. At
this time confidence is not on which solution is more correct so
will stay close to the latest guidance for both precipitation
chances and temperatures through the weekend into early next week.
Despite the differences between the models over the weekend it
does appear a break in the heat can be expected for western Kansas
this weekend into early next week. Could easily have highs Sunday
and Monday only in the 70s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 602 PM CDT Tue Jun 20 2017
Scattered thunderstorms will move southward across west central and
southwest Kansas through late this evening, potentially affecting
all TAF sites with MVFR cigs/vsbys. Brief IFR vsbys will be possible
with the strongest storms. Otherwise, VFR conditions will prevail at
all TAF sites through late Wednesday morning. Other than convective
outflow winds from thunderstorms gusting in excess of 30 to 40kt,
southerly winds 10 to 25kt will persist through early Wednesday
as a lee side trough of low pressure remains anchored across
eastern Colorado.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 70 97 69 96 / 30 10 30 0
GCK 69 101 67 100 / 70 20 30 10
EHA 67 101 66 100 / 30 20 40 10
LBL 69 100 68 100 / 20 10 40 10
HYS 70 97 70 96 / 60 20 30 10
P28 70 95 69 95 / 20 0 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...JJohnson
Area Forecast Discussion
National Weather Service GRAND JUNCTION CO
1004 PM MDT Tue Jun 20 2017
.UPDATE...
Issued at 1001 PM MDT Tue Jun 20 2017
Added mention and increased coverage of showers and isolated
storms for areas north of I-70 as a shortwave continues to track
across northern portions of the CWA keeping shower and storm
activity ongoing through the evening. HRRR is picking up on this
better than most models and shows showers continuing to track
eastward through the early morning hours before dissipating. Not
getting much precip out of these showers with mainly gusty outflow
winds the primary concern with a few lightning strikes here and
there.
&&
.SHORT TERM...(Tonight through Wednesday night)
Issued at 200 PM MDT Tue Jun 20 2017
A large upper-level ridge analyzed at 596 DM over central Arizona remains
firmly in control of the weather over the western CONUS this
Tuesday afternoon. Along the northern fringes of this ridge, some
mid-level moisture and a bit of faster flow aloft has resulted in
convective development over the higher terrain of the Great Basin
and middle Colorado River valley this afternoon. In northeastern
Utah, around 500 j/kg of mixed-layer CAPE will fuel a few
convective showers through the afternoon. Dry air near the surface as
evidenced in model and observed soundings does not bode well for
precipitation making it to the ground, however some locations in
the Roan, Tavaputs, and eastern Uintas may see a hundredth or two
out of any stronger cells that develop. Dry lightning will be a
low, but not non-existent, threat this afternoon as one or two of
the strongest cells may grow high enough above the freezing
level to form graupel. Any convection will quickly wane after
sunset this evening as daytime heating is lost. Temperatures this
afternoon look on track as of 2pm, and will run near or just
slightly below record values for the day.
Despite 500mb heights lowering by 2-4 DM over the region
tomorrow...an uptick in winds aloft, some slight WAA from the
southwest, and a bit better mixing will likely make Wednesday the
warmest day of the year across the Four Corners. Slightly faster
flow aloft will aid any convection that develops in the higher
terrain north of I-70, and PoPs have been adjusted slightly upward
in this package.
.LONG TERM...(Thursday through Tuesday)
Issued at 200 PM MDT Tue Jun 20 2017
The main forecast challenge in the long term will be with winds on
Thursday. Forecast soundings from the NAM/GFS indicate the
potential for mixing down winds of 20mph with some 30+ mph gusts
across eastern Utah and especially northwest Colorado. The ECMWF
is much less bullish regarding wind speeds at the surface, as it
models the 300mb jet streak weaker and faster than its American
counterparts. Due to the continued low confidence in this
forecast, have opted to refrain from any Fire Weather headlines on
Thursday for now. Future shifts will continue to monitor the
forecast for any changes.
After the passage of a weak frontal boundary on Friday morning,
the heat wave will ease a bit as we head into the weekend. Some
afternoon cloud cover will help curtail the warmth on Friday
afternoon. Heights will lower notably by Saturday and Sunday.
While temperatures are still expected to remain about 5 degrees
above average, they will be 10 or so degrees cooler than the
midweek-heat currently gripping the region.
Late in the weekend, guidance is in fairly good agreement
developing a new ridge of high pressure over the desert southwest.
Eastern Utah and western Colorado will be on the eastern fringes
of this ridge, and forecast models indicate a bit of lingering
mid-level moisture lingering around the Continental Divide early
next week. This would result in a better chance for showers and
thunderstorms in the mountains than we have seen in recent days,
before the ridge kicks this moisture east by midweek. Despite a
relatively benign weather pattern upon first glance, there are
certainly plenty of subtle forecast challenges to monitor through
next week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 748 PM MDT Tue Jun 20 2017
Scattered showers along and north of the I-70 corridor will
persist this evening. There is a low chance that KASE and KEGE
will see additional showers. Thunderstorms over the eastern Uinta
Mountains may generate a strong outflow at KVEL before midnight.
Otherwise, VFR conditions and CIGS above 18,000 feet MSL will
continue through the night and through midday Wednesday. Showers
and thunderstorms are expected over the mountains Wednesday
afternoon resulting in conditions similar to today.
&&
.FIRE WEATHER...
Issued at 200 PM MDT Tue Jun 20 2017
Dry weather will continue over much of the forecast domain with
only a small chance of convective activity in the Roan and
Tavaputs as well as the eastern Uintas. Only trace amounts of
precipitation are expected out of any development in these
locations over the next two days. A low chance of some lightning
does exist with any shower that develops. Winds will increase
slightly during the afternoon on Thursday as a weak mid-level jet
moves overhead. Under full mixing, some of these winds may
translate to the surface resulting in near-critical Fire Weather
conditions on Thursday. Confidence remains low on this borderline
event and will not issue headlines as of this afternoon forecast
package.
&&
.HYDROLOGY...
Issued at 200 PM MDT Tue Jun 20 2017
A flood advisory has been issued for the Roaring Fork River in
Aspen as snowmelt and tunnel closures upstream have caused the
river to reach bankfull. This advisory will run through Friday
evening.
A number of streams and creeks also continue to run strong, cold,
and high and will continue to do so through the week. Where water
is running high, river banks may become saturated and unstable.
Lowlands along the rivers may also become inundated with water.
Remember if you are going to raft, kayak or tube on the rivers be
sure to always wear a life jacket.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...Heat Advisory until 10 PM MDT Thursday for COZ006.
UT...Heat Advisory until 10 PM MDT Thursday for UTZ022-027-029.
&&
$$
UPDATE...MDA
SHORT TERM...MAC
LONG TERM...MAC
AVIATION...NL
FIRE WEATHER...TGJT
HYDROLOGY...TGJT
Area Forecast Discussion
National Weather Service Indianapolis IN
1023 PM EDT Tue Jun 20 2017
.UPDATE...
The AVIATION Section has been updated below.
&&
.SYNOPSIS...
Issued at 330 PM EDT Tue Jun 20 2017
Some chances for storms early tonight across the northern counties
will give way to dry conditions for central Indiana for the most
part until the remainder of a tropical system interacts with a
frontal system to bring rain and thunderstorm chances across the
area for Thursday night through Friday night. The front moving
through will bring lesser chances for precip to the area until
Sunday night once it has passed. Then dry, cooler weather moves
in.
&&
.NEAR TERM /Overnight/...
Issued at 941 PM EDT Tue Jun 20 2017
A weak trough of low pressure was push across Central Indiana this
evening. Weak instability along with the effects from daytime
heating have allowed a few light rain showers and isolated
thunderstorms to push across the area.
HRRR shows a gradual dissipation of the showers and storms over
the next few hours as heating is lost and best forcing is lost.
Furthermore good subsidence remains in place near the Ohio
River...which also should hamper further development and
progression. Thus based upon radar trends have trendy pops high
downstream of the echos...but have trended toward a dry forecast
overnight as the forcing and instability is lost.
Trended lows slightly cooler than the previous forecast...mainly
across the northern areas that have seen some light rain fall.
&&
.SHORT TERM /Wednesday through Friday/...
Issued at 330 PM EDT Tue Jun 20 2017
On Wednesday surface high pressure and weak upper ridging will be
over the area. These features currently look like they will be
sufficient to quell any chances for showers along the washed out
front during the day. For the most part dry weather will then
continue until midday Thursday. By that point could see some low
chances for thunderstorms start to move in from the south ahead of
the tropical system. By late Thursday night a cold front will move
toward the area from the northwest while the tropical remnants
approach from the south. The highest chances for precipitation will
be across the south. During the day Friday precipitation chances and
amounts will increase as the bulk of the tropical moisture is drawn
north and interacts with the aforementioned frontal boundary making
rain likely and bringing chances for thunderstorms across most of
the area. At this point bulk of model guidance keeps the axis of
heaviest rainfall to the south of the forecast area, but this will
be something to watch going forward.
Highs Wednesday will likely be a couple degrees warmer than today
with some warming at 850 mb and a mostly sunny day expected.
Thursday should again be warm with a strong flow of warm moist air
into the area. Friday though should see cloudy skies with the
tropical remnants drawing further north, and this additional cloud
cover should cap highs off in the low 80s.
&&
.LONG TERM /Friday Night through Tuesday/...
Issued at 253 PM EDT Tue Jun 20 2017
Showers and a few thunderstorms will linger into Friday night as a
front across central Indiana moves on to the south. The front will
be far enough south Saturday for Indiana to be dry. Models...
especially the european indicate a weather disturbance may bring
chance POPS around Sunday...then mostly dry weather will occur
Sunday night through Tuesday as high pressure over the central
plains moves towards the Ohio valley.
Temperatures will be cooler than normal...especially Sunday and
Monday.
Highs will be in the upper 70s to lower 80s Saturday and again
Tuesday and in the 70s Sunday and Monday. Lows will be in the lower
to middle 60s Friday night...around 60 Saturday night and 50s Sunday
and Monday night. Generally stayed close to model initialized
temperatures.
&&
.AVIATION /Discussion for the 210300Z KIND TAF Update/...
Issued at 1023 PM EDT Tue Jun 20 2017
Scattered showers continue along an upper level disturbance from
central Indiana back into east central Illinois. Threat for showers
in the vicinity of the KIND terminal will linger for a few more
hours.
Will also make some adjustments to the wind forecast for the next
several hours as winds expected to gradually veer around to the
south or southeast in the wake of outflow boundary.
Previous discussion follows.
Upper level disturbance currently dropping southeast from the
Great Lakes resulting in scattered convection over northern
Illinois. Short term model guidance suggests this feature will
pass over the terminals through about 210400Z. Instability axis
runs from northern Indiana back into west central Illinois, with
the air mass locally still fairly stable, so threat for lightning
strikes should diminish with time this evening, but some
scattered showers may linger longer into the evening. Best threat
for lightning strikes at this time appears to be in the KLAF/KHUF
vicinity, closest to instability axis. CB bases around 060.
Briefly gusty and shifting winds possible near shower activity.
Otherwise, scattered to broken clouds above 050 tonight. Surface
winds 220-250 degrees at 8-12 kts early this evening expected to
diminish to 6 kts or less late tonight.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CP
NEAR TERM...Puma
SHORT TERM...CP
LONG TERM....JH
AVIATION...JAS
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
1047 PM EDT Tue Jun 20 2017
.UPDATE...
Issued at 1047 PM EDT TUE JUN 20 2017
WSR-88D still picking up on a few isolated rain showers and/or
sprinkles. These will remain light and most spots will remain dry
tonight. Updated to allow a bit more time on the sprinkles and
also updated clouds with latest obs and satellite trends. Also,
the clouds are playing a role in keeping temperatures a bit warmer
than the current temperature curve. Therefore, adjusted the curve
some to better match trends.
UPDATE Issued at 857 PM EDT TUE JUN 20 2017
Despite surface high pressure, a 500MB wave and 300mb divergence
is just enough to POP off a rain shower or sprinkle this evening
based on WSR-88D radar this hour. The HRRR seems to be handling
this fairly well and will somewhat lean toward it with edits. For
now will update to add in sprinkles at most for a couple of hour.
These will be showers will be light and are expected to dissipate
over the next couple of hours.
UPDATE Issued at 625 PM EDT TUE JUN 20 2017
Surface high pressure continues to build into the region and
matter of fact the highest pressure reading nearby is at CSV in
the TN Valley region. Overall this and mixing will lead to a drier
night and based on crossover temps not as much fog. However, while
the CU will dissipate and we will be left with mostly high clouds
streaming in from the SW. No major changes needed for this update
but did load in the latest obs and trends.
&&
.SHORT TERM...(This evening through Wednesday night)
Issued at 359 PM EDT TUE JUN 20 2017
The latest surface map features broad high pressure across the
mid-Mississippi Valley, with Tropical Storm Cindy located across
the central Gulf of Mexico. Aloft, a strong ridge remains poised
across the Desert Southwest, with troughing in the northeastern
quadrant of the CONUS. Eastern Kentucky has been enjoying dry
weather, with temperatures in the low to mid 80s and dew points
down as low as the lower 50s in places at times.
Dry weather will continue through the rest of the short term, as
high pressure remains nosed in from the east southeast through the
column. Tonight will feature a mostly clear night, with lows
ranging from the mid 50s in some of the cooler valleys, and lower
60s on the ridges. Wednesday will feature a warmer day, with highs
in the mid 80s, and dew points also a bit higher.
The moisture will make a bigger increase through Wednesday night,
as thicker high clouds stream in from the approach of Cindy. Lows
will be in the mid to upper 60s.
.LONG TERM...(Thursday through Tuesday)
Issued at 359 PM EDT TUE JUN 20 2017
The extended portion of the forecast begins on Thursday with the
upper level pattern favoring a more northern track with the jet
leaving the central and southern CONUS under weak flow to begin the
extended. Focus of the extended will be on the approach of the
remnants of or rather a still organized Tropical Depression
possible moving into Kentucky. Models have wavered a bit on the
track and QPF amounts but overall have kept a consistent time period
of rainfall. As the surface tropical low track north and northeast
around the mid level ridge parked over the southeastern CONUS it
will track east into KY and the TN Valley. At this point the system
interacts with a cold front dropping from the western Great Lakes
southeast into the Ohio Valley. Models have indicated, though
slightly inconsistent on the placement of the heaviest band of
precip, that this interaction with the front and the deep rich
tropical moisture will produce the heaviest rainfall during the Sat
00Z to 12Z period. Model soundings during this time indicate a 2
inch plus PWAT over eastern Kentucky. However, the inconsistency of
models and the lessened QPF of WPC 12Z solution has made the case to
reduce QPF a bit so added a 50% blend to the super blend from the
WPC run. Thus have gotten a more reasonable QPF amount and in
agreement with the neighboring offices. So will continue to mention
the heavy rainfall threat in the HWO for Friday through Saturday
night with the best chance being Friday night into Saturday.
By Sunday, expect a brief period of dry weather before the next
disturbance tracks east across the mid MS Valley into eastern
Kentucky by Sunday afternoon. The front will hang up along the
middle Appalachians keeping the chance of precip lasting from Sunday
afternoon into Monday afternoon. Confidence at this point is not
very high given the uncertainty of the track of the remnants of
Tropical system Cindy. Thus pop chances will be slight for Sunday
night through Monday night.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 728 PM EDT TUE JUN 20 2017
We will remain VFR for the period as surface high pressure
remains in control. Most sites are drier and crossover temps are
not likely to be met. Therefore, fog will be limited to the
deeper valley locations tonight. Kept the TAFs simple with CU
disipating and only high to mid clouds expected overnight. The
latest model soundings do show moisture at the 7k ft level again
Wednesday afternoon and added this to the TAF. Winds will remain
light, but west to southwest winds of 5 to 10 knots will mix down
wednesday afternoon.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...GEOGERIAN
LONG TERM...SHALLENBERGER
AVIATION...DJ
East Central Florida Forecast Discussion
National Weather Service Melbourne FL
939 PM EDT Tue Jun 20 2017
.DISCUSSION...
MLB radar shows isold showers over the open waters and recent
decictions of 2KM WRF and HRRR show at least isold activity
continuing over the open waters and Gulf Stream overnight. The
updated forecast keeps a slight chance (20%) for showers with a
storm or two psbl over the Gulf Stream. Lows quite mild once again
in the upper 70s along the coast and mid 70s inland.
Prev disc...
Wednesday...Little change in the overall weather pattern with a
squeeze play between the Atlantic ridge to our east and Tropical
Storm Cindy to our west. This will maintain deep southeast flow
through the mid-levels. Expect a similar evolution of convection
to today with isolated maritime showers moving onshore the
Treasure Coast in the morning, transitioning to diurnally driven
showers across the interior in the afternoon. Models indicate
slightly better moisture developing during the second half of the
day, so will carry 40-50% PoPs west of the St. John`s River.
Elsewhere, 20-30% will suffice.
Thursday and Friday...Surface high pressure ridge axis north of the
area will keep a sustained southeasterly flow. For Thursday the best
chance of showers and thunderstorms will be over the interior
locations in the afternoon and evening with the inland moving sea
breezes. The southeasterly flow continues on Friday but only have a
slight chance of showers and thunderstorms as PWATs are forecast to
be quite a bit lower than on Thursday. The "best" chance looks to be
south of a line from Kissimmee to Melbourne where the GFS depicts
wave of slightly higher PWATs moving into this area during the
afternoon hours.
Highs on Thursday and Friday will top out in the lows 90s inland and
upper 80s to near 90 along coastal areas. Lows will continue above
average with the persistent onshore flow. Mid 70s in most areas with
some locations near the coast staying in the upper 70s.
Saturday-Sunday...Mid level ridge builds east of the area and
extends across the peninsula over the weekend through Sunday. This
will bring some mid level drying to the area and lower mean
moisture levels. Should see a more typical summer sea breeze
regime with 20-30 percent rain chances near the coast and around
40 percent across the interior through Sunday.
Monday-Tuesday...Rain chances will increase slightly Monday/Tuesday
into the 30-50 percent range as a deep layer trough moves into the
northern portion of the state and deep moisture ahead of the trough
moves across East Central Florida.
&&
.AVIATION...
Dry conditions expected overnight with a low chance for onshore
moving showers along the Treasure/Space Coasts.
&&
.MARINE...
Tonight...With the Atlantic Ridge to our east and Tropical Storm
Cindy to our west, southeast flow will continue. A tighter pressure
gradient will support 15 - 20 knots over the open waters, south of
Cape Canaveral. Will carry Small Craft Exercise Caution headlines
over the Brevard and Treasure Coast waters through tonight. Seas up
to 4 feet nearshore and 5 feet offshore.
Wed...SSE winds to around 15 knots the first half of the day will
decrease to 10-15 knots in the afternoon. Seas 3-4 ft nearshore
and up to 4-5 ft offshore.
Thursday-Saturday...Winds/seas subside a bit as the Atlantic ridge
axis drops back southward. SE to S winds 10 knots with seas 2-4 ft
with isolated showers and storms expected.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&
$$
JP/AC
Area Forecast Discussion
National Weather Service Morristown TN
940 PM EDT Tue Jun 20 2017
.DISCUSSION...
Latest IR imagery shows fairly extensive cirrus shield extending
NE out of the Gulf Of Mexico and across the Tennessee Valley this
evening as Tropical Storm Cindy sits in the Northern Gulf. With
forecast for a northward drift expected overnight, do not expect
to see any end to cirrus ceilings area wide. Updated forecast to
reflect increased cloudiness through tonight.
Additionally, decreased POP`s in SW NC for remainder of the night
as radar echoes are beginning to weaken S of the area and any pcpn
looks to remain S of the area through the overnight hours, in
agreement with latest HiRes HRRR and RAP13.
Tweaked temperatures/dew points slightly in order to bring in
line with latest observations. Dew points have dropped into the
upper 50s and lower 60s across much of the area, helping to make
it feel a little cooler and drier on this Summer Solstice...which
occurs at 12:24 AM tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 68 85 70 82 / 10 20 30 70
Knoxville McGhee Tyson Airport, TN 66 85 68 82 / 10 10 10 50
Oak Ridge, TN 65 87 68 82 / 10 10 10 50
Tri Cities Airport, TN 61 84 64 81 / 10 10 10 40
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...None.
TN...None.
VA...None.
&&
$$
EJH
Area Forecast Discussion
National Weather Service Pueblo CO
324 PM MDT Tue Jun 20 2017
.SHORT TERM...(This evening through Wednesday)
Issued at 324 PM MDT Tue Jun 20 2017
Currently...
Skies mostly sunny for the most part across the cwa. ISolated
thunderstorms were noted over the S Sangres S of KTAD. Towering
cumulus were noted along the mtns, and along a lee trough that
extended from E of KLAA down towards Kim, CO.
It was quite warm across the region with temps in the 90s across
nearly all of the plains. The warmest temp was in Pueblo with a
reading of 97F.
Instability was quite high east of the lee trough, with MLCAPE of
3500 J/KG with effective shear values of about 20 knots.
Rest of the afternoon...
One or two strong to marginally severe thunderstorms will be
possible along and east of the lee trough this afternoon into early
this evening. Storms should push off to the east-southeast and
should move into KS by early evening.
Other storms will be possible along the mtns/plains interface,
especially south of Canon City.
This evening into tonight...
Simulations show that a weak short wave will move across the region
late this evening into the early morning hours. The HRRR has been
pretty consistent on indicating one or two storms will form across
the Pikes Peak region around 10-11 pm and move east-southeast across
the plains. For this reason have included some low POPs across this
region for later this evening.
Otherwise, expect mostly clear skies across the region with low
temps 60s plains and 40s and 50s in the mtns.
Tomorrow...
We should see an uptick in convection across most of the cwa
tomorrow afternoon as a weak boundary is expected to move down the
plain. Temps tomorrow will actually be a degree or two higher
tomorrow. Boundary should stall over far se CO and this will be a
focusing area for convection. SPC has this area in marginal risk
tomorrow and given the instability and inverted V soundings, strong
gusty winds and some hail may be an concern.
Mtns/plains interface may also see a slightly better chance of some
thunder tomorrow along with a couple of storms in the interior mtn
locations. Several 100F readings are likely along the lower ark rvr
valley tomorrow. /Hodanish
.LONG TERM...(Wednesday night through Tuesday)
Issued at 324 PM MDT Tue Jun 20 2017
...Cooling down for the Weekend...
Wednesday night-Friday...Weak to moderate west to northwest flow
aloft continues to be advertised across the State, with the center of
large upper high across southern Arizona and southern New Mexico,
and several embedded waves moving through the stronger flow aloft
across the Northern Tier of States. Any high based convection across
the area late Wednesday afternoon looks to diminish with the setting
of the sun Wednesday evening. A stronger wave moving across the
northern Rockies Wednesday night sends a front across the eastern
Plains through the day Thursday, with low level moisture pooling
along and behind the front. This front will be the focus for storms
across eastern Colorado Thursday afternoon and evening, as it pushes
southeast and west across all of the southeastern plains by early
Friday morning. There could be a few stronger storms across northern
portions of the area, generally along and north of the Palmer Dvd
into northeastern Colorado, where the best shear will be located.
Slightly cooler temperatures will be noted across the area Thursday,
with a more noticeable cool down expected on Friday, with highs
mainly in the 70s and 80s across the lower elevations and mainly
50s and 60s across the higher terrain. Morning stratus and
easterly upslope flow look to keep the eastern plains too stable
on Friday, though with the upslope flow, will likely see some
storms develop across the eastern mountains and immediate adjacent
plains Friday afternoon and evening.
Saturday-Sunday...Models differ on Saturday, with the latest ECMWF
still indicating another surge of cooler air digging across the area
on Saturday, whereas the latest GFS is not as strong with the push
of cooler air, keeping the main front across the northern high
plains through the period. The GFS keeps moist south to southeast
flow across the area Saturday and Sunday, owning to better chances
of afternoon showers and storms, especially across the southeast
mountains and plains, where as the EC solution would keep the plains
generally too stable. For now, stayed close to model blended
solutions which keeps slight chances across eastern Colorado through
the weekend. Either way, temperatures look to stay generally below
seasonal levels through the weekend.
Monday-Tuesday...Upper level ridging rebuilds across the Desert SW
and into the Great Basin, supporting a warming trend back to around
seasonal levels into early next week. Some moisture embedded within
the weak northwest flow aloft will also support increasing chances
of afternoon and evening showers and storms across the area, most
notable across the higher terrain.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 324 PM MDT Tue Jun 20 2017
VFR conditions through the next 24 hours. winds will be diurnally
driven tonight. A weak weather disturbance will move across east
central CO late this evening and there is a very slight chance of
some -TSRA in the vicinity of KCOS between roughly around 05-06 UTC
later this evening.
A weak surge will come down the plains tomorrow morning and this may
keep the winds northeasterly at KCOS and KPUB a good part of the day
before becoming upslope late in the afternoon. There will also be an
outside chance of a TSRA at KPUB and KCOS tomorrow afternoon.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HODANISH
LONG TERM...MW
AVIATION...HODANISH
Area Forecast Discussion
National Weather Service Blacksburg VA
920 PM EDT Tue Jun 20 2017
.SYNOPSIS...
Variable cloudiness for tonight as a stalled front lifts
northeast across southeastern Virginia. Weak high pressure
remains in control on Wednesday. Weather turns increasingly more
unsettled into Friday and Saturday with several periods of rain
and embedded thunderstorms.
&&
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
As of 920 PM EDT Tuesday...
Added a few showers in the west early tonight as highlighted on
HRRR and HiResW-ARW-east, and continue light pops across
southern portions of forecast area as frontal boundary lifts
northward overnight into Wednesday morning. Modified cloud cover
to capture sharp cloud gradient on satellite image. Made some
minor adjustments in low temperatures to allow for cooler
readings in the north with less cloud cover. Have a good night!
As of 710 PM EDT Tuesday...
Made some minor adjustments in temperatures for this evening
utilizing surface obs with their trends and shaped towards
glamp tonight. Slowed the drop of temperatures in the south
with additional cloud cover. Trimmed back northern edge of light
pops for the overnight.
As of 325 PM EDT Tuesday...
Overall a pleasant afternoon across the central Appalachians and
into the Piedmont, along with a much-needed dry repreive from
several prior days of wet weather conditions. Broad trough exists at
500 mb across the Great Lakes region, with upper-level moisture/high
clouds stemming from circulation associated with what is now
Tropical Storm Cindy in the central Gulf streaming northeastward.
Weak surface ridge in place across the northern two-thirds of the
forecast area, with a stalled frontal zone which trails across
eastern VA into the central VA Piedmont and into Upstate SC.
For Tonight: Generally quiet conditions tonight. Toward mid-
evening, will watch a a mid-level shortwave trough embedded in
the broad Great Lakes trough lift some of the deeper moisture
associated with the stalled front back northeastward. The net
effect this will have, though, is for an increase in clouds
across the southeastern tier of counties in VA and in the
Piedmont counties in NC. There may even be a isolated light
shower from these but the prospect of that is not high. Honestly
waffled between whether or not to call it a sprinkle or light
shower, so definitely not significant. Patchy river fog will
again be possible outside of the cloud shield and particularly
in the New River and Greenbrier Valleys into the lower Tennessee
Valley. Lows should be pretty similar to last night, in the mid
50s to near 60 east of the Blue Ridge and some 5-7 degrees
warmer east of the Blue Ridge into the Piedmont.
For Wednesday and Wednesday Night: Any light showers associated with
the frontal wave dissipates by mid-morning, along with any river
valley fog. Deeper west to northwest flow develops during the day,
with mostly sunny to partly cloudy skies (mainly fair weather
cloudiness with high clouds interspersed) from mid-morning through
early evening. While most of the evening hours are dry, will be
returning into a warm, moist advection pattern especially late in
the night. Look for mostly clear skies to start, but with an
increase in mid-level clouds late across the far southwest mountains
of VA and the High Country of NC. Overall, looking for highs
Wednesday in the upper 70s to mid/upper 80s (warmest northeast),
with light west to southwest winds. Lows should be a few degrees
warmer than tonight in the upper 50s to middle 60s, tending to occur
a few hrs before sunrise with the increase in warm advection.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 324 PM EDT Tuesday...
Transition to tropical/muggy airmass commences this period as upper
ridge of 588 to 590 DM builds across the southeast U.S. while what
is now Tropical Storm Cindy heads into the LA/TX area.
Westerlies aloft will stay north of us, from the northern Plains to
the mid-Atlantic Thursday. Should see less of a threat Thursday of
storm coverage, as models seem to confine activity more over the
Southern Appalachians west and southwest to the Gulf Coast. With
convergence in the low level winds and increase in moisture will
still see a few showers/storms fire up in the afternoon. Best threat
likes over the NC mountains/foothills into the Mountain Empire of
Southwest VA. At the moment flooding threat looks marginal.
Thursday night into Friday night, Cindy is expect to shift northward
into Arkansas. A deeper northern stream shortwave will move across
Ontario/Hudson bay digging a trough over the midwest, and causing
heights to fall over our area. Models indicate a few pieces of
energy moving east ahead of Cindy with potential for heavier rains
shifting from KY/TN east/northeast to the Central Appalachians.
Precipitable water values will be increasing to 1.5 to 2.0 inches
and right now, rainfall Friday will be heavy at times, but still
some question on where greatest corridor of rain will fall, with 12z
GFS/ECM very close in having northern KY into Ohio, northern WV as
the area to get the higher amounts. Given some uncertainty should
still be a limited threat of localized flooding from downpours. As
far as svr threat, thinking is with more clouds/tropical like
soundings, the storms should stay sub-severe.
Lows this period will be warm, about 5-8 degrees above normal
ranging from the lower to mid 60s mountains, to around 70 to lower
70s east of the Blue Ridge.
Thursday appears a little less cloudy in the east, so will see
temperatures reach the mid 80s, possibly near 90 east of Danville,
while the mountains get into the mid 70s to around 80.
Friday should be a few degrees cooler with more clouds/rain around,
but still noticeably muggy in the 70s mountains, to lower to mid 80s
east.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 148 PM EDT Tuesday...
Still looking muggy and showery this weekend, especially Saturday as
remnants of now Tropical Storm Cindy get pooled in along a cold
front moving in from the northwest. Model solutions favor Cindy
weakening/eroding but some have it staying situated back over the
mid MS Valley behind the front into Saturday then getting kicked
east ahead of digging northern stream trough.
So in terms of precip chances, Saturday looks like a good soaker,
Sunday is iffy as but still chance is there with frontal boundary in
the vicinity. Northern stream front moves across Monday morning so,
overall Monday/Tuesday look drier and a little cooler.
Temperatures this weekend will be seasonal but muggy, with highs in
the mid to upper 70s west to lower to mid 80s east.
Still early on flooding concerns with 12z GFS a little lower on QPF
into Sunday keeping higher amounts west of the Appalachians. Will
ease off some on the HWO wording, but localized flooding will remain
the main concern.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
As of 719 PM EDT Tuesday...
VFR conditions will continue at the taf sites this evening into
tonight. In general, some SCT CU expected with some high level
clouds especially in southern portions.
Tonight into Wednesday morning, the frontal boundary`s
northeast advance may push MVFR clouds, SCT020 to BKN020 into
KDAN. There may even be an isolated unrestricted shower or
sprinkle. With such a high clouds base, have low confidence
in precipitation. However, the NAM and HRRR still support
an isolated showers across the extreme southeast portion of
the forecast area. Radiation fog is possible with higher
confidence of MVFR/temporary IFR visibilities at KLWB and
KBCB. Potential is there at KLYH as well but a little less
confident there as it will depend on extent of cloudiness. Held
on to some light fog after 09z for Lynchburg. Winds should
trend light and variable tonight.
Should trend VFR again Wednesday, though like today, greater
low to mid-level cloud cover further southeast. Winds again
become west to southwest 4-8 kts.
Extended Aviation Discussion...
Generally VFR Wednesday late afternoon through Thursday
afternoon. Low-confidence prospect for radiation fog Wednesday
evening into Wednesday night.
More active aviation forecast period Thursday evening into the
weekend. Lowering, sub-VFR conditions anticipated Thursday
evening into Friday with first surge of showers advancing SW to
NE. Potential for low-level wind shear western terminals.
Continuation of sub-VFR conditions Friday evening into Saturday with
moderate to at-times heavy rain. Confidence is low on timing of
rain. The unsettled weather continues Sunday into Monday with
sub-VFR condition possible with convection.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...AL
NEAR TERM...AL/KK
SHORT TERM...WP
LONG TERM...RAB/WP
AVIATION...AL/KK