Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/05/16
Area Forecast Discussion
National Weather Service Albany NY
1025 PM EDT Tue Oct 4 2016
.SYNOPSIS...
Mostly cloudy skies will gradually give way to more
breaks this evening as an upper level storm moves away from the
area. High pressure will then move over the region over the next few
days, allowing for dry conditions with temperatures moderating above
normal through Friday. Hurricane Matthew may impact the eastern
seaboard this weekend and its effects, if any, on eastern New York
and western New England are still unknown at this time.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
As of 1025 PM EDT...Not much change as 11u-3.9u satellite imagery
reveals scattered stratocu clouds across the region. However,
additional breaks have been observed as heights continue to climb
and low level anticyclonic flow increases, expectations are for the
subsidence layer to lower further per our 00Z sounding which should
aid in breaking up the stratus deck overnight. Then some patchy fog
should develop as we will add to the grids at this time.
Prev Disc...An upper level low continue to be situated just east
of the region near the coast of southern New England. This is the
same storm system that has been impacting our region over the past
week, and its finally starting to slide eastward and lose its
influence on our area. Upper level ridging is now building over
the area, with rising heights and temps aloft.
Although both water vapor imagery and the 18z KALY sounding shows
plenty of dry air in place at mid levels, there remains lots of
low stratus clouds over the area. This is thanks to some low level
moisture trapped beneath a strong inversion at 725 mb, which is
very evident on the recent sounding as well. The low-level
moisture has been supplemented by a weak easterly flow at low
levels off the western Atlantic Ocean, which has resulted in
mostly cloudy skies over much of the region.
As the upper level low continue to move away tonight, clouds
should start to break up tonight as drier air starts to move into
the region. Model soundings and 3km HRRR guidance all suggest sky
cover will improve to partly cloudy to mostly clear by later
tonight. With the clearing skies, light winds and lingering low-
level moisture, some patchy fog may develop in some spots, such as
in valleys and near bodies of water.
Overnight lows will be cooler than recent nights due to the
clearing skies. Most areas look to fall into mid to upper 40s
tonight.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
Dry and quiet weather with warming temperatures is expected
during the entire short-term period.
Surface high pressure will be anchored over New England with
warming temps aloft and upper level ridging in place. 850 hpa
temps will warm from near +7 degrees C on Wednesday to as warm as
+13 C on Friday. Plenty of sunshine is expected each day with
clear skies at night. Some patchy fog is possible each night thanks
to the good radiational cooling in place.
High temps look to reach into the upper 60s to low 70s on
Wednesday, mid 70s on Thursday and mid to possibly upper 70s on
Friday. Overnight lows for Wednesday and Thursday nights look to
be in the 40s.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
The main forecast challenge in the long term period is where
Hurricane Matthew tracks and if it has any impact or influence on
our weather over the weekend.
Model guidance has shifted dramatically this afternoon with the
latest 12z guidance. Several major models (ECMWF, GFS, and GGEM)
and the 12z GEFS mean have all shifted with their track on the
storm. The latest GFS/GGEM/GEFS all are further east with the
storm as it reaches off the Northeast coast this weekend, while
the latest ECMWF keeps the storm spinning off the coast of the
Southeast. All of this is related to how the hurricane interacts
with a shortwave trough (and associated cold front) which moves
from the Great Lakes towards the Northeast this weekend. All of
this uncertainty within the guidance and run-to-run inconsistency
lowers the confidence on the current forecast.
For now, we have gone with a dry forecast for Friday night with
lows falling into the 40s. Over the weekend, we are currently
going with chc pops for rain showers. Even if Matthew stays
south/east, there will be chance for some rain as the northern
stream cold front moves across the area. If some tropical moisture
is able to get pulled northward, there could be some locally
heavier rainfall along or ahead of the front thanks to higher
PWAT air, otherwise, it could be just some typical frontal
showers. If the latest models are all wrong and the earlier runs
are more correct (such as yesterdays or last night`s runs), there
could be a more direct impact of the storm passing closer to the
area with more significant rainfall and wind. At this point, its
too early to pin down specifics, so we recommend to keep up with
the latest local forecasts and latest advisories from the
National Hurricane Center, which are updated every 6 hours on
their website: www.hurricanes.gov
With the current forecast for expected clouds and precip, temps
look a little cooler on Saturday with highs in the 60s. Behind
the departing cold front (and possibly coastal storm), it looks
even cooler for Sunday with highs in the low 50s to low 60s, with
clouds eventually breaking for some sunshine.
By early next week, it looks dry and cool for Monday (Columbus
Day) with high pressure nearby. High temps may only be in the 50s
with a mix of sun and clouds. Another cold front may be moving
towards the area for Tuesday with another chance for rain showers
and some passing clouds. Highs once again look in the 50s to low
60s for Tuesday.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Diverse cloud coverage across the region as we range from CLR to
MVFR CIGS. As evident in our 00Z sounding, the inversion layer is
lowering but moisture remains a bit trapped. So clouds continue
to linger across the area as moisture is trapped under an
inversion as we will continue with mainly SCT-BKN MVFR CIGS (even
where skies are clear at the moment). Cloud cover is expected to
gradually erode as drier air works in with mostly clear skies
developing tonight. With clearing skies and calm winds
radiational fog is expected to form. IFR conditions are expected
to develop at the terminals with mainly TEMPO groups. The fog
will lift and burn off after sunrise with a clear day on tap for
Wednesday with ridging over region at all levels of the
atmosphere.
Outlook...
Wednesday Night through Friday Night: No Operational Impact. NO
SIG WX.
Saturday through Sunday: Moderate Operational Impact. Chance of
SHRA.
&&
.FIRE WEATHER...
RH values will be near 100 percent tonight with some dew and fog
formation. Wind will be very light or calm tonight. Clouds will
gradually break up overnight, but no precipitation is expected.
During the day tomorrow and Thursday, it will continue to be dry
with a partly to mostly sunny sky. RH values will fall to 40 to
55 percent with light and variable winds.
The next chance for a wetting rainfall may be this weekend.
&&
.HYDROLOGY...
The latest US Drought Monitor continues to show drought
conditions across much of the region. Precipitation departures
this calendar year have been 3 to 12 inches below normal, with the
greatest departures across southeastern parts of the HSA. As a
result, streamflow and ground water levels have been running below
normal.
High pressure will dominate the weather through Friday with dry
conditions and no precipitation. This will allow rivers and
streams to hold steady through much of the week.
The next system to watch will be Hurricane Matthew, which is
currently in the Caribbean Sea. It looks to track north off the
coast of Florida over the next few days and eventually northeast
off the eastern seaboard. It is still too early to say if this
storm will have any direct impact on the HSA. If there was to be
any impact, it would be over the weekend. Even without Matthew
directly impacting the area, a cold front may bring some showers
to the region for Saturday into Sunday, although the amounts of
rainfall with this front will also depend on the track of the
tropical system.
For details on specific area rivers and lakes, including observed
and forecast river stages and lake elevations, please visit the
Advanced Hydrologic Prediction Service /AHPS/ graphs on our website.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.
&&
$$
SYNOPSIS...Frugis
NEAR TERM...Frugis/BGM
SHORT TERM...Frugis
LONG TERM...Frugis
AVIATION...IAA/BGM
FIRE WEATHER...Frugis
HYDROLOGY...Frugis
Area Forecast Discussion
National Weather Service Grand Forks ND
654 PM CDT Tue Oct 4 2016
.UPDATE...
Issued at 649 PM CDT Tue Oct 4 2016
500 mb upper low and sfc low continues to slowly move north and
near the ND/MT/SK border. Shortwave trough seen in water vapor
from eastern nebraska into southeastern ND lifting NNE. Increasing
area of rain entering SE ND and now WC MN. This area will lift NNE
this evening. Raised pops a bit more and expanded higher pops a
tad west more into the RRV as well. Sfc front located on western
edge of this short wave trough roughly from the low in far nw ND
through the Rugby-Harvey area to west of Valley City-Aberdeen.
&&
.SHORT TERM...(This evening through Wednesday)
Issued at 335 PM CDT Tue Oct 4 2016
Placement of precipitation as well as strength will be the main
challenges for the period.
The upper low will continue to lift northeast across the Northern
Rockies and Northern Plains. The first round of precip is entering
southeastern ND and west central MN as a lead shortwave is
rotating through and the surface cold front approaches. The HRRR
has been doing a decent job with the current convection and they
continue to have the band of rain lifting north along the RRV late
this afternoon. It then shifts the main rain area eastward into
MN, which makes sense as a more significant shortwave currently
over western SD/Neb lifts northeast and the cold front pushes
through. Current elevated CAPE values are around 500 J/kg and this
is not expected to change too much. Deep layer bulk shear values
are around 40-50 kts, and as the low level jet kicks in over the
eastern forecast area this evening some intensification of storms
is possible. However, think the greatest threat will be heavy
rainfall as the rain trains northward and some areas in the
southeastern counties could see over an inch of accumulation.
The upper low will continue to slowly move over the Northern
Plains and southern Canada tomorrow. With the front pushed most of
the way through think the overnight showers will be pushing off
through the northeastern counties at daybreak. However, wrap
around showers will begin to enter the northwestern counties by
late in the day. Temperatures will be much much cooler with highs
mainly in the 50s and some spots staying in the upper 40s.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 335 PM CDT Tue Oct 4 2016
No major precipitation chances throughout the period as winds and
frost/freeze potential will be the main concerns.
The period begins with an upper low continuing to spin across
southern Saskatchewan/Manitoba before it finally begins to propagate
off towards Hudson Bay. The associated trough will be slow to pull
away from the area so a few lingering rain/snow showers near the
international border, along with gusty west/northwesterly winds,
will persist as the trough pulls away and weak upper ridging builds
in. Cool surface high pressure building into the Northern Plains by
late in the week will keep conditions dry heading into the weekend
before northwest upper flow returns.
Below normal temperatures will persist for the first half of the
period with highs struggling to get into the 50s. Thursday night
will bring the first chance of a hard freeze to the Devils Lake
basin with chances spreading south and eastward for an even colder
Friday night. Did go a few degrees lower than guidance for Friday
night with the surface high passing directly over the area. Warmer
air will return late in the weekend and early next week with highs
back into the 50s/lower 60s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 649 PM CDT Tue Oct 4 2016
Several hours of rain this evening RRV into NW MN. Thunder risk is
very low. Ceilings mostly MVFR in rain area...briefly IFR with
some vsby reductions and or low clouds. Overall though as short
wave trough moves through a dry slot over DVL basin and central Nd
will spread NE into the RRV overnight. Timing of this dry slot and
rise of MVFR cigs to more high/mid clouds is tricky and will be
monitored. Gusty south-southeast winds ahead of trough will
diminish overnight.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...Riddle
SHORT TERM...JR
LONG TERM...Lee
AVIATION...Riddle
Area Forecast Discussion
National Weather Service Wilmington NC
1128 PM EDT Tue Oct 4 2016
.SYNOPSIS...
Strong high pressure will build from the north through the mid-
week period. The center of the high will slide well offshore from
the NE states allowing powerful Hurricane Matthew to move
northward through the Bahamas Wednesday and up the Southeast
U.S. Coast Thursday thru Saturday, possibly skirting the immediate
coasts of the Carolinas before finally exiting northeast of the
area by Sunday. Given this far out in time, this latest Matthew
path in the vicinity of the Carolinas will likely be tweaked due
to continued updates from the National Hurricane Center. Cool high
pressure will build back across the area from the west early next
week.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
As of 1045 PM Tuesday...Have took out the low chance pops for the
coastal areas south of Cape Fear for the overnight period into
daytime Wed morning. The latest HRRR and RAP show that the pcpn
comes back onshore during the pre-dawn Wed hours mainly from Cape
Fear northward. It remains on the light side in the form of light
rain or light rainshowers, with the QPF having also been updated.
Previous.........................................................
As of 715 PM Tuesday...This update concerned with increasing the
opaque cloudiness across much of the ILM CWA based on latest model
output and trends. Have kept the rain chances slight along the
immediate coast with little if any deviation from the previous
update. If a drier trend is established at 1st look of the 00z
models, may take out the rain chances altogether for the immediate
coast at the next update. In addition, with this cloud blanket,
especially east of the I-95 corridor, have tweaked min temps
upwards by a degree or 3. NE winds to stay frisky along the
immediate coast, and will likely stay refreshed well inland. This
will keep any fog formation at bay.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
As of 3 PM Tuesday...Gradually the offshore rain chances edge
landward this period and by late Thursday, likely rain chances are
advertised along the coast. QPF values remain however on the low
side Wednesday and most of Thursday, until 1/4-1/2 inches of rain
falls Thursday night. because of the pressure gradient between a
high pressure wedge to the north and lower pressure S-SE of the
area, moderate NE winds will prevail through the period, gusty at
beaches to 25 mph occasionally. No coastal flooding is expected at
area beaches however through Thursday. Late thursday night both
winds and rain chances will begin to increase. With clouds and NE
flow daily diurnal ranges remain narrow, highs in the middle and
upper 70s and lows in the upper 60s to middle 70s. Late Thursday
night Matthew should be located just offshore of Cape Canaveral.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 3 PM Tuesday...Long term will be marked by 2 significant
features. The first will be Matthew, chewing its way up the coast
Fri and moving across the area Sat. While there remains
uncertainty with respect to the storm`s track and strength, it is
likely there will be significant impacts from this storm within
the forecast area. Excessive rainfall is expected with 10 inches
or more possible in some locations. Significant rainfall in the
area over the last 30 days will increase the likelihood of
widespread downed trees. Surge will also be a concern but will
depend on the track and is something that will be narrowed down
as time passes. Further refinements to the track and strength
forecast are likely and the finer details will become clearer as
the weekend draws closer.
Following Matthew ridging at the surface and aloft will build over
the region. The surface high will build in from the northwest early
next week, sliding overhead late in the period. Flat ridging aloft
will extend across much of the southern CONUS with much drier and
cooler conditions in place for the beginning of next week.
Temperatures Sun through Tue will be below climo with highs in the
upper 60s to lower 70s and lows in the low to mid 50s.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
As of 00Z...VFR this evening. Increasing low level moisture will
result in the development of stratus cigs generally after midnight.
Wind speeds should maintain VFR vsbys. Confidence is high IFR cigs
will develop at KFLO/KLBT. Cigs could fall into the LIFR range but
confidence is low. Generally MVFR cigs will develop at the coastal
terminals.
As the morning progresses IFR cigs at KFLO/KLBT will improve into
the the MVFR category. MVFR cigs likely coastal terminals the entire
day. KLBT/KFLO will possibly improve to low VFR during the late
afternoon.
Winds will be NE through the period, gusting to around 20 kt at
times, highest and most often at the coastal terminals. Some
intermittent -RA possible coastal terminals through the TAF period.
EXTENDED OUTLOOK...THU, VFR inland terminals, MVFR coastal
terminals. Reduced flight restrictions due to low clouds/rain/breezy
and gusty winds are possible Friday through Saturday as Hurricane
Matthew tracks along or near the Southeast U.S. coast.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
As of 1045 PM Tuesday...This update concerned with the placement
of the low pops for either rw- or r- for the overnight period into
daylight Wed. Via the latest HRRR and RAP models, the waters from
Cape Fear northward will have the possibility of seeing pcpn move
back across the local waters. South of Cape Fear, from the present
to sunrise Wed, have kept the pops for rw- or r- just offshore.
Winds updated earlier still look in the ballpark. Significant seas
will range 5 to 7 ft except as low as 3 to 4 ft nearshore in the
protected areas with a NE wind, ie. South of Cape Fear to Murrells
Inlet.
Previous......................................................
As of 730 PM Tuesday...Strong SCA to continue overnight into Wed
mainly a result of the 1030+ MB high offshore from the NE states
but continuing to ridge SW to and across the SE States.
This update concerned with increasing the NE winds and gusts
slightly by several kts to account for latest local buoy trends
and the latest model consensus projected sfc pg. Current seas
forecast remains in the ballpark and see no reason to tweak attm.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 3 PM Tuesday...Gradually the offshore rain chances edge
landward this period and by late Thursday, likely rain chances are
advertised along the coast. QPF values remain however on the low
side Wednesday and most of Thursday, until 1/4-1/2 inches of rain
falls Thursday night. because of the pressure gradient between a
high pressure wedge to the north and lower pressure S-SE of the
area, moderate NE winds will prevail through the period, gusty at
beaches to 25 mph occasionally. No coastal flooding is expected
at area beaches however through Thursday. Late thursday night both
winds and rain chances will begin to increase. With clouds and NE
flow daily diurnal ranges remain narrow, highs in the middle and
upper 70s and lows in the upper 60s to middle 70s. Late Thursday
night Matthew should be located just offshore of Cape Canaveral.
LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 3 PM Tuesday...Treacherous marine conditions are expected
through the period with headlines likely Fri through Sun. Based on
the latest forecast from NHC east to northeast winds will already
be near tropical storm force as the period begins and seas will be
running in the double digit range. Conditions will deteriorate Fri
night into Sat with the worst conditions expected Sat morning into
early afternoon. Offshore winds start decreasing Sat night into
Sun following the exit of Matthew but seas will remain above 6 ft
for much of Sun.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...Beach Hazards Statement from 8 AM EDT Wednesday through
Wednesday evening for SCZ054-056.
NC...Beach Hazards Statement from 8 AM EDT Wednesday through
Wednesday evening for NCZ106-108.
MARINE...Small Craft Advisory until 6 AM EDT Thursday for AMZ250-252-
254-256.
&&
$$
SYNOPSIS...dch
NEAR TERM...DCH
SHORT TERM...MJC
LONG TERM...III
AVIATION...MRR
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
631 PM CDT Tue Oct 4 2016
.SHORT TERM...
255 PM CDT
Tonight...
Slow and perhaps just partial clearing of the overcast ceilings
will allow temperatures to fall into the lower 60s but
persistent southeasterly flow will keep lows considerably warmer
than average for early October. Precip chances increase from west
to east toward daybreak as an upper trough swings toward the area
ahead of the large low pressure system positioned across the
Northern Plains. The best moisture transport appears to be focused
west of the area closer to the surface boundary, so have only
carried chance to slight chances of rain locally.
Lenning
&&
.LONG TERM...
313 PM CDT
Wednesday through Tuesday...
A challenging latter half of the week presents itself with rain
chances Wednesday-Friday, including some thunder potential within
that, but definitely not a washout through that entire period. In
fact, temperatures look to be above to well above normal if some
sun can be realized, before a drop into the weekend.
The upper air pattern remains amplified and blocked on Wednesday
and Thursday, with a broad and baggy yet strong upper trough
across the western half of the U.S., and an anomalous ridge
across the east. Within the western trough, a couple potent waves
will be rotating through, one resulting in a deep surface low
across far southern Canada on Wednesday. An associated occluding
and weakening front will push east into the area Wednesday. Ahead
of this, a 40 kt low level jet and associated ribbon of moisture
transport forecast by the RAP and NAM will veer into northern
Illinois Wednesday morning. Convection expected tonight to our
west over Iowa will likely gradually weaken in the early morning
as the parent short wave translates more northeast, however
isolated to scattered showers, possibly with some storms, may
traverse across the CWA. A weak focus/confluence is left from the
dying front by Wednesday afternoon, and have maintained some low
chances of showers/storms east in the afternoon and evening, but
not particularly excited about those.
Temperatures on Wednesday are tricky with cloud cover potentially
playing a role. Have continued the gradual warming trend from
today and what is being observed upstream across southern Illinois
and Indiana (highs of 75 to 80).
The next short wave trough will round the base of the primary
upper low and move into the Central Plains by later Thursday. A
warm front is likely to lift north over the area on Thursday,
though it may be slowed/enhanced by quite a bit of morning clouds
as indicated by some guidance. The greater lift for rain is
focused to the northwest of the area given the forecast jet
placement, however moisture looks to steadily increase over the
local area with 60s dew points returning into the warm frontal
zone. So do have chances for showers and storms increasing, with
the highest chances in the northern and western CWA Thursday and
Thursday Night. The chance for stronger storms is non-zero but
depends on how deep and far east the low moves up the boundary.
Highs on Thursday could again vary quite a bit, but feeling more
confident of at least 80 being reached south of I-80 and possible
areawide.
For Friday and Friday Night, have continued to go with a blend of
the slower GFS and quicker EC with the cold frontal passage, as
can see equal chances of either at this time. Have a gut feeling a
slower solution than the EC will pan out given the ridge to the
east and even possibly to some degree the approach of Hurricane
Matthew, but unsure if as slow as the GFS. The slower the front
passes on Friday, the more likely it would be to have post-frontal
rain into Friday evening. Conditions behind the front should turn
breezy with temperatures dropping.
Highs on Saturday in northern locations still look to fall short
of 60 even with some differences in the models, and Saturday and
Sunday night both look cool. There could be some 30s in outlying
locations depending on just how cool the low-level air mass
remains as it spreads southeast.
MTF
&&
.AVIATION...
For the 00Z TAFs...
No significant weather through tonight with just a gentle E
turning SE breeze. Southerly winds will increase by mid-late
morning Wednesday and probably become somewhat gusty. Extent of
cloud cover leaves magnitude of gustiness in question, less dense
cloud cover would result in stronger gusts than in the 00 UTC
TAFs. There could be some scattered showers around during the day
Wednesday, but duration not expected to be long and not
anticipating significant impact to aviation operations at this
time, so just included long duration VCSH until timing can be
pinned down better in later TAFs. Winds will ease toward sunset
Wednesday evening.
Izzi
&&
.MARINE...
255 PM CDT
Relatively light southeasterly flow will gradually strengthen
overnight and turn more southerly. This will allow for a period of
greater wave growth tomorrow, especially across the north half.
Waves begin to subside again later tomorrow as winds relax
somewhat and veer more southwesterly. Friday night a frontal
passage will usher in cooler and stronger northwesterly winds.
Lenning
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion...Updated
National Weather Service Saint Louis MO
918 PM CDT TUE OCT 4 2016
.UPDATE...
Issued at 901 PM CDT Tue Oct 4 2016
Bands of showers and storms over northwest MO and eastern KS will
shift eastward into northeast and central MO late tonight as upper
level divergence increases ahead of an approaching upper level
trough and as a south-southwesterly low level jet brings
increasing low level moisture into the area. This convection
should weaken as it moves into the St Louis metro area around 12Z
Wednesday. Lows tonight will be warmer than the previous night due
to increasing cloud cover along with stronger southeasterly/south-
southwesterly surface/low level winds. Lows tonight will be 10 to
15 degrees above normal for early October.
GKS
&&
.SHORT TERM... (Through Late Wednesday Afternoon)
Issued at 334 PM CDT Tue Oct 4 2016
Still expect this evening to be mainly dry across the area as
showers and thunderstorms are still out over eastern Kansas and
northwest Missouri. GFS and NAM are in good agreement that a deep
trough currently over High Plains will move northeast to near the
Mississippi River by 12Z tomorrow morning. The RAP shows low level
moisture convergence increasing over central Missouri by 06Z that
moves east towards the Mississippi River by 12Z. This will be under
mid-level ascent from the trough. Have gone with likely PoPs
overnight across central Missouri with likely and high chance PoPs
into southeast and east central Missouri as well and southwest
Illinois on Wednesday morning as the forcing begins to weaken and
move eastward. By Wednesday afternoon there will only be some weak
residual low level forcing across southeast Missouri into south
central Illinois. Will keep a chance of showers and thunderstorms
going over the southeast half of the CWA.
Stuck close to the GFS/NAM MOS guidance which matches up well
tonight and tomorrow.
Britt
.LONG TERM... (Wednesday Night through Next Tuesday)
Issued at 334 PM CDT Tue Oct 4 2016
The stacked low over south central Canada Wednesday night will
continue moving northeast. Mid and upper level parts of the system
will begin opening up which should help increase the forward speed
of the system Thursday night and Friday as it continues to lift.
The longwave pattern won`t change much with Hurricane Matthew
blocking things up. Therefore warm/moist southwest flow with a
decent chance of rain...primarily across central and northeast
Missouri and west central Illinois will continue Wednesday night
and Thursday.
Meanwhile another shortwave will move southeast across the Rockies
and dig into the base of the longwave trof. The GFS and NAM move
the longwave east more slowly since they amplify the pattern more
when the shortwave digs in. The ECMWF keeps the shortwave moving
rather than using that energy to amplify the pattern which results
in the cold front passing through our area early Friday morning
rather than Friday afternoon as the NAM and GFS show. Obviously the
slower GFS/NAM solution would mean a warmer Friday for most of the
area along with a greater chance for rain and thunderstorms. This
is more consistent with our current forecast and I would prefer to
see more consensus before changing Friday`s forecast from "warm and
wet" to "cooler and dry". The GFS keeps some lingering post-frontal
precip over the area. This looks to be in response to the passing
of the mid-upper level shortwave and all of its associated broad
scale lift. Think some light rain or sprinkles look plausible.
A 1029mb high comes roaring in Saturday behind the front which
will bring us temperatures as much as 15 to 20 degrees cooler than
Friday`s were. High pressure remains in control of the weather at
least through Monday. Some weak moisture return may cause a few
showers Monday night or Tuesday according to the ECMWF, but the
GFS is dry. Slight chance PoPs on ensemble guidance look like a
good compromise given the uncertainty. Saturday and Sunday look
seasonably cool, with gradual warming back to near or above normal
temperatures on Tuesday.
Carney
&&
.AVIATION... (For the 00z TAFs through 00z Wednesday Evening)
Issued at 637 PM CDT Tue Oct 4 2016
An upper level disturbance and weakening surface trough along
with a southwesterly low level jet will lead to a band of showers
and storms which will move southeastward through the taf sites
late tonight and Wednesday morning. This activity will be
weakening by the time it gets to the St Louis metro area. There
may be a brief period of MVFR cigs and vsbys as the convection
moves through, but otherwise prevailing VFR conditions will
continue. Southeasterly surface winds will veer around to a south-
southwesterly direction Wednesday morning.
SPECIFICS FOR KSTL: An upper level disturbance and weakening
surface trough along with a southwesterly low level jet will lead
to a band of showers and storms which will move southeastward
through the STL area Wednesday morning. This activity will be
weakening by the time it gets to STL with little thunder expected
by this time. There may be a brief period of MVFR cigs and vsbys
as the convection moves through, but otherwise prevailing VFR
conditions will continue. Southeasterly surface winds will veer
around to a south-southwesterly direction Wednesday morning.
GKS
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 67 82 67 86 / 20 50 20 20
Quincy 62 80 65 83 / 50 30 40 60
Columbia 61 81 66 83 / 60 30 40 50
Jefferson City 62 82 66 86 / 60 30 40 40
Salem 64 81 64 85 / 10 30 10 5
Farmington 62 80 64 84 / 10 50 5 5
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion...UPDATED
National Weather Service Miami FL
1104 PM EDT Tue Oct 4 2016
...HURRICANE WARNINGS NOW IN EFFECT FOR PALM BEACH AND BROWARD
COUNTIES, LAKE OKEECHOBEE, AND PORTIONS OF THE ATLANTIC WATERS...
...TROPICAL STORM WARNINGS NOW IN EFFECT FOR MIAMI-DADE, MAINLAND
MONROE, INLAND COLLIER, GLADES, AND HENDRY COUNTIES, AS WELL AS
BISCAYNE BAY...
.UPDATE...
As of 1104 PM EDT...Hurricane Warnings and Tropical Storm
Warnings have been issued for the following areas:
Hurricane Warning: Palm Beach county, Broward county, Lake
Okeechobee, and all Atlantic waters outside of Biscayne Bay
Tropical Storm Warning: Miami-Dade, Glades, Hendry, Mainland
Monroe, and inland Collier counties, as well as Biscayne Bay
Currently, coastal Collier county and the Gulf waters do not have
any watches or warnings in effect at this time.
Hurricane Matthew continues to move northward off the eastern tip
of Cuba, and remains a dangerous Category 4 hurricane with maximum
sustained winds of 130 mph and a minimum central pressure of 950
hPa. Matthew is still forecast to cross the eastern tip of Cuba
tonight and then move into the Bahamas Wednesday. The storm is
still forecast to approach the east coast of Florida Thursday.
Regardless of the exact track, Matthew will be a very dangerous
hurricane that will bring direct impacts to South Florida for the
first time since Hurricane Wilma in 2005.
Key Message:
Now is the time to finish hurricane preparedness plans. Wednesday
will be the last day to prepare before the storm - conditions will
rapidly deteriorate late Wednesday night, with dangerous and
life-threatening conditions expected by Thursday morning
especially along the east coast.
Potential Impacts:
Wind - potential extensive wind damage across Palm Beach and
Broward counties, and significant wind damage across the remainder
of South Florida.
Storm surge - possible significant storm surge along Palm Beach
and Broward counties, with storm surge also possible in other
vulnerable areas along the remainder of the Atlantic coast
including Biscayne Bay.
Rainfall - locally heavy rainfall will be possible through Friday,
mainly along the east coast with localized flooding possible
especially in vulnerable low lying and urban areas.
Tornadoes - isolated tornadoes will be possible as early as
Wednesday night as outer rainbands impact the region ahead of
Matthew.
Other significant hazards - Large pounding waves of 20-40 feet
and greater will lead to beach erosion along with life-threatening
rip currents along the Atlantic coast through the weekend.
THIS IS A POTENTIALLY DANGEROUS AND LIFE-THREATENING SITUATION.
All interests in South Florida are urged to continue closely
monitoring the latest forecasts from the National Hurricane Center
and National Weather Service Miami. Do not focus on the exact
track. Any further shifts in the track to the west may increase
the threat for hurricane conditions across the remainder of South
Florida. Everyone should continue to bring their hurricane
preparations to completion during the day Wednesday.
&&
.PREV DISCUSSION... /issued 833 PM EDT Tue Oct 4 2016/
UPDATE...
..Hurricane and Tropical Storm Watches continue to remain in
effect for portions of South Florida, and all of the local
Atlantic waters...
As of 830 PM EDT...Current forecast for tonight remains on track
with only minor updates made to account for the latest trends in
observations. Over the next few hours, scattered showers and
thunderstorms will continue to be possible over portions of the
interior and Gulf Coast. Overnight, additional scattered showers
and storms will be possible mainly over the Atlantic waters and
portions of the east coast. The last few HRRR runs have been
picking up on another round of convection moving through the
Atlantic waters and towards the east coast around daybreak. Will
need to monitor this trend closely as embedded squalls with gusty
winds will be possible with this activity.
As of the latest 8 pm National Hurricane Center advisory,
Hurricane Matthew continues to move northward at 9 mph near the
eastern tip of Cuba. Matthew continues to remain a dangerous
Category 4 hurricane with maximum sustained winds of 140 mph and a
minimum central pressure of 949 hPa. Due to interaction with
nearby higher terrain in Cuba, Matthew is slightly weaker this
evening than earlier in the day, although slight reintensification
is still possible as it moves into a more favorable environment in
the Bahamas. For more detailed information on the latest forecast
and potential impacts regarding Matthew, see the previous forecast
discussion below and latest Hurricane Local Statement.
PREV DISCUSSION... /issued 724 PM EDT Tue Oct 4 2016/
AVIATION...
Generally VFR flying conditions are expected to prevail overnight
at the TAF sites outside of MVFR/IFR associated with scattered
thunderstorms. The best chance for IFR this evening will be at
KAPF where ongoing convection will continue over the next few
hours. Overnight, VCSH will prevail, with VCTS possible at all TAF
sites by 16-17z Wednesday. Will need to keep an eye on the
approach of outer rainbands associated with Hurricane Matthew at
the east coast TAF sites, which could bring squalls with gusty
winds during the afternoon and evening hours.
Winds will be easterly around 10 knots this evening, diminishing
to 5-10 knots overnight, and increasing to around 10 knots with
occasional gusts to 20 knots for the east coast sites Wednesday.
PREV DISCUSSION... /issued 516 PM EDT Tue Oct 4 2016/
HURRICANE AND TROPICAL STORM WATCHES IN EFFECT FOR PORTIONS OF
MAINLAND SOUTH FLORIDA...
HURRICANE WATCH IN EFFECT FOR PORTIONS OF THE ATLANTIC WATERS...
TROPICAL STORM WATCH IN EFFECT FOR PORTIONS OF ATLANTIC WATERS...
TROPICAL STORM WATCH IN EFFECT FOR BISCAYNE BAY AND LAKE OKEECHOBEE...
DISCUSSION...
Forecast for tonight through Wednesday: Hurricane Matthew is
forecast to move generally northward tonight then northwestward
across the Southern Bahamas into Wednesday. As it does so, deep
tropical moisture and increasing cloudiness and steadily
increasing winds are expected across the region. Bands of showers
and scattered thunderstorms well in advance of the hurricane will
be possible tonight into Wednesday. By Wednesday afternoon and
evening more widespread showers and thunderstorms are forecast
across the Atlantic waters and Atlantic metro areas.
As of 11 AM EDT, a Hurricane Watch is in effect for portions of
mainland South Florida and portions of the Atlantic Waters. A
Tropical Storm Watch is in effect for portions of mainland South
Florida and portions of the Atlantic waters, including Biscayne
Bay and Lake Okeechobee. As for intensity and timing, Hurricane
Matthew is expected to be a major hurricane and is forecast to
cross the Bahamas on Wednesday and across the Northwest Bahamas on
Thursday.
With additional updates from the National Hurricane Center this
afternoon and evening, changes to the watches or potential
warnings are possible and all local products will be updated
accordingly.
Primary threats for South Florida: At this time primarily wind.
Additional threats include hazardous marine conditions and beach
erosion. Currently hurricane force winds are not forecast for the
South Florida peninsula, but given the uncertainties there still
remains a reasonable chance for portions of Broward and Palm Beach
counties.
Additional threats to South Florida, but more minor, include storm
surge, flooding rains and tornadoes. The forecast winds with
Matthew will not be favorable for storm surge inundation along the
Atlantic coastal zone. In general peak winds will be along or off
shore. Therefore, while storm surge is expected to be elevated
mainly along the Palm Beach county coast, forecast levels are
similar to inundations from astronomically high tides in flood
prone areas along the coastal zone. The flooding rain threat and
tornado threat, while elevated across portions of South Florida,
are also minor. For flood potential, while locally high rainfall
in isolated areas is entirely possible, the forecast of Matthew
indicates that as it gets closer to South Florida it is expected
to accelerate. This should aid in reducing potential rainfall
accumulations. For tornado potential, there will be an elevated
threat mainly across the eastern peninsula but it is not moderate
or high as the greatest threat for tornadoes is normally on the
northeast quadrant of the hurricane, and in this scenario South
Florida will be in the western to southwestern quadrants.
For the updated specifics to the track for Hurricane Matthew,
please consult the latest products from the National Hurricane
Center. For potential impacts for South Florida, please continue
to monitor products issued from the National Weather Service in
Miami.
MARINE...
As hurricane Matthew approaches South Florida, extremely
dangerous and hazardous marine conditions are likely for the
local Atlantic waters beginning Wednesday night and continuing
through at least Friday. In addition, winds and waves will be
locally higher with bands of showers and thunderstorms well ahead
of Matthew.
AVIATION...
Afternoon convection has popped up west of the east coast
terminals, with APF possibly seeing more convection in the area
later in the afternoon. The potential exists for a secondary round
of thunderstorms after sunset along the east coast. Storms could
bring MVFR cigs and IFR/LIFR vsbys in heavy rain if they impact a
terminal directly.
BEACH FORECAST...
As Hurricane Matthew approaches the region Wednesday night,
conditions will rapidly deteriorate at all Atlantic beaches, with
dangerous conditions likely including life- threatening rip
currents, significant beach erosion, and significant waves and
swell. Coastal flooding due to wave set-up and run-up will also be
a threat and dependent upon the eventual track of Matthew,
especially across Broward and Palm Beach counties.
&&
.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach 80 88 83 88 / 30 70 70 80
Fort Lauderdale 80 87 81 88 / 30 80 70 80
Miami 79 89 81 89 / 40 70 60 80
Naples 75 90 79 88 / 50 50 20 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...Tropical Storm Watch for FLZ063-066-070-073-074-173-174.
Hurricane Watch for FLZ067-068-071-072-168-172.
AM...Tropical Storm Watch for AMZ630.
Hurricane Watch for AMZ610-650-651-670-671.
GM...None.
&&
$$
DISCUSSION...60/BD
MARINE...60/BD
AVIATION...92/IRL
UPDATE...92/IRL
BEACH FORECAST...60/BD
Area Forecast Discussion
National Weather Service Marquette MI
707 PM EDT Tue Oct 4 2016
.SHORT TERM...(This evening through Wednesday)
Issued at 324 PM EDT TUE OCT 4 2016
Water vapor imagery and RAP analysis show a mid-upper level trough
over the Northern Plains with a vigorous shortwave over ern MT and a
downstream ridge over the Great Lakes. Ahead of the trough and its
associated cold front, there is an area of shra/tsra from eastern
ND/western IA as noted on regional radar imagery. Closer to home,
some light shra popped up over scntrl Upper Mi this morning and
lifted north into MQT county during the day, but it appears from
webcams that much of this pcpn has now ended.
Tonight, the vigorous shortwave now over se MT will drift ne to the
ND/Saskatchewan border while a shortwave trough pivots ne thru the
Plains toward the Upper Mississippi valley. This shortwave trough
will help propel the cold front to ne MN/western WI by 12z Wed.
Models generally still in good agreement on timing of pcpn
associated with shortwave/cold front, although the 12z GFS may be
slightly faster than the rest of the model guidance. Will continue
to carry schc to low chc pops reaching only western Gogebic
County/far western Ontonagon county 10-11z. Tight pres
gradient/southerly winds and precipitable water near 1 inch will
lead to an unseasonably warm night for early Oct. Min temps in the
mid 50s to around 60F will be around 20 degrees above normal and
will be more typical of normal max temps at this time of year. May
have a good chance of breaking record high minimum temperature of 54
for date (10/5) here at NWS MQT.
Wed...Deep shrtwv/low pres over far sw Manitoba on Wed morning are
fcst to move slowly to the ne thru the day. The attendant weak cold
front and deep moisture axis/deep layer q-vector convergence assoc
with the front wl cross the Upper Lakes on Wed accompanied by a band
of showers and perhaps a TS as MLCAPEs rise 200-300 j/kg. Even
though pwat near 1.50 inches wl be 200-250 pct of normal, passage of
the stronger shrtwv/forcing well to the nw and quick moving
front/and deep moisture axis wl limit pcpn totals. Vigorous deep
layer drying/q-vector divergence in the wake of the cold fropa wl
end the pcpn and even allow for a return of some sunshine by late in
the day over the w. Since the airmass following the fropa wl be
Pacific in origin under a sw flow aloft between the lingering wrn
trough and the persistent upper ridge over the se CONUS, expect max
temps to remain above normal...well into the 60s to lower 70s.
.LONG TERM...(Wednesday night through Tuesday)
Issued at 335 PM EDT TUE OCT 4 2016
Deep trough over the western conus gradually moves to the central
Conus by Fri morning. Trough then slides across Great Lakes and
eastern Canada through the weekend as Hurricane Matthew rides along
the east coast. At the sfc, strong low pressure system southern
Manitoba to northern Ontario slides to northern Ontario and Hudson
Bay by Thu helping to push a cold front across the Upper Great
Lakes. Even though the front will be east of Upper Michigan on Thu
another shortwave lifting ahead of the larger trough may bring some
showers to Upper Michigan. Much better chance for rain arrives Thu
night into Fri morning as stronger shortwave and deepening low
pressure system lift across the Upper Great Lakes.
GFS keeps showers or stratiform rain into Fri evening in right
entrance region of jet streak while ECMWF is more aggressive in
moving the trough aloft through and the jet farther east. Latest GFS
is quicker than 06z run in bringing in drier weather for Fri night
though. Dry punch aloft forecast Thu night into Fri will lead to
steep lapse rates aloft and possible embedded thunder/heavier rain
rates.
Low and associated cold front move through and airmass in wake of
the front does look cooler than seen for a while as H85 temps fall
blo 0c. Expect daytime highs for the weekend to stay in the 50s
across Upper Michigan. Trough axis with deeper moisture and the cool
temps should support chances for lake effect rain showers with delta
t/s over 15c. Some hint that sfc trough may be over Lk Superior and
Upper Michigan later Sat into Sat night. Convergence from the sfc
trough and over-water instabiilty and depth of convective layer
suggest there may be waterspout potential for the weekend. Too
early to get those details in there yet though.
High pressure moves in later in the weekend, then another sfc trough
will move through on Mon. Larger scale forcing looks minimal so not
looking at a lot of rain. After a cool weekend, temps will rebound
back toward normal. Could see a couple cool nights Sat night or Sun
night as the high slides across the region.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 707 PM EDT TUE OCT 4 2016
Expect VFR conditions to continue at all 3 terminals tonight, but
then cigs will begin to lower toward MVFR Wed morning with advance
of frontal system and associated band of showers from Plains.
Conditions will return to VFR at all sites Wed afternoon after the
front passes.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 324 PM EDT TUE OCT 4 2016
SE to S winds less than 20 knots will generally be on a gradual
increase late tonight thru Wed morning as a cold front approaches
from the west. Winds will become strongest over north central and
eastern Lake Superior, reaching the 20-30kt range late tonight/Wed.
The cold front will sweep across Lake Superior Wed aftn/evening.
While SW winds as high as 15-25kt should occur behind the front Wed
night into Thu morning, strongest between Isle Royale and the
Keweenaw Peninsula, the pressure gradient and winds will weaken for
a time Thu aftn and night as a low pressure trough develops over the
Upper Lakes ahead of a low pressure wave developing over the
southern Plains. After this low pressure wave passes late Thu
night/early Fri morning, NW winds up to 20-25kt will develop on Fri,
strongest over the e half of Lake Superior. NW winds up to 20kt will
linger into Sat.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Voss
LONG TERM...JLA
AVIATION...07
MARINE...Voss
Area Forecast Discussion
National Weather Service Spokane WA
534 PM PDT Tue Oct 4 2016
.SYNOPSIS...
Cool conditions with occasional wet periods will continue through
the beginning of the weekend. A drying and slightly warmer break
period may develop late this weekend through Monday...but
unsettled conditions may return by Tuesday.
&&
.DISCUSSION...
Evening update to add isolated showers and thunderstorms across
the Waterville Plateau and Western Basin. The combination of a
second wave crossing the Cascades and instability from sunshine
this afternoon has lead to isolated showers and t-storms over the
last few hours with a bulk of the activity currently stretching
from Bridgeport to Moses Lake to Mattawa. HRRR suggest this
activity will continue to expand into a line and drift east into
the Okanogan Highlands...Central Columbia Basin. I am skeptical
with any HRRR run given its performance or lack of throughout
today and will wait to buy into this solution until I see more
consistency run to run.
The rain and showers across Ern WA and N ID are weakening some
with the exception of the Palouse. Looks like more showers
developing along the WA/OR border which will continue to drift
into the Palouse and L-C Valley for the next few hours. /sb
&&
.AVIATION...
00Z TAFS: One frontal band bringing a band of showers through
Idaho and far eastern reaches of WA while a second...which is
utilizing aftn instability...is delivering showers across the
Western Columbia Basin. Activity arnd Moses Lake is a bit more
convective and has resulted in a few lightning strikes. Expect
this activity to persist for the next few hours then the
focus will switch toward possible restrictions from stratus or
patchy fog. Overall, low confidence regarding exact ceiling
heights and restrictions but will mention in sct-bkn form with
moist upsloping flow and small temperature/dewpoint ranges as
sunset approaches. /sb
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 42 57 43 57 43 54 / 30 30 20 30 10 70
Coeur d`Alene 43 56 43 55 42 50 / 60 50 20 50 10 70
Pullman 40 57 41 57 41 56 / 80 40 20 30 10 60
Lewiston 46 61 46 62 46 60 / 50 40 20 30 10 40
Colville 39 60 39 59 39 58 / 10 30 20 20 20 80
Sandpoint 38 54 39 54 37 53 / 80 50 20 50 20 80
Kellogg 40 52 39 52 39 49 / 70 60 30 60 10 70
Moses Lake 41 63 39 65 43 63 / 40 20 10 10 10 50
Wenatchee 46 61 45 65 48 59 / 30 30 10 10 20 60
Omak 42 63 43 64 44 58 / 20 20 10 20 20 70
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
Area Forecast Discussion
National Weather Service Norman OK
623 PM CDT TUE OCT 4 2016
.DISCUSSION...
The 00Z aviation discussion follows....
&&
.AVIATION...
Isolated strong/severe TSRA will continue until a few hours after
sunset--mainly over north-central Oklahoma. Winds west of a
dryline (located approximately KAVK-KCSM-KHBR-KLTS-F05 at 2300Z)
will become generally light and variable after sunset. Elsewhere,
10-15 kt winds from the S-SE will continue through the period.
Winds should be somewhat lighter on Wednesday. There will be
another chance of TSRA tomorrow afternoon and evening (mainly in
the general vicinity of I-44), but chances are currently too low
to include in the TAFs.
CmS
&&
.PREV DISCUSSION... /issued 310 PM CDT TUE OCT 4 2016/
DISCUSSION...
Isolated severe thunderstorms may develop along the dryline late
this afternoon. Various convective-allowing models (HRRR/HRRRX/4KM
NAM) are persistent in discrete supercells developing across
southwest Oklahoma and moving northeastward into central Oklahoma.
Analysis of the HRRR indicates localized backing/increased
convergence along a dryline bulge could be a factor for convective
iniation in the models. Visible satellite imagery indicates a
possible perturbation/ascent across western north Texas/southwest
Oklahoma which might be aiding in pressure falls/localized
backing. There is some evidence of this perturbation on the 700
mb flow.
Vertical wind shear will be more than sufficient for supercells with
potential for large hail and damaging wind gusts. By around 00Z, low-
level (0-1 km) vertical wind shear (~20 knots), MLLCLs (<1 km),
and critical angles (~90 degrees) will result in sufficient
environment for potential tornadogenesis with any supercells.
Tomorrow, at least isolated showers/storms will be possible with a
moist, conditionally unstable airmass still in place.
Coverage/confidence for storms is low with no significant forcing.
Coverage may increase overnight as isentropic ascent increases.
By late Thursday into Thursday night, a seasonably strong cold front
will progress from northwest to southeast across Oklahoma/western
north Texas. Severe weather will be possible; however, because of
linear forcing along the cold front, the primary hazards will be
gusty winds and locally heavy rainfall. Lingering showers/storms
will be possible Friday morning across southern Oklahoma/western
north Texas.
Much drier/cooler air is expected in the front`s wake on Friday and
Saturday. Many locations will drop into the 40Fs by Saturday
morning, and with dew points dropping into the 30Fs and light
winds, some locations across northwest Oklahoma may drop into the
upper 30Fs.
By Sunday, a shortwave trough may increase the chance of showers,
especially northwest Oklahoma. The forecast becomes more uncertain
beyond Sunday as the GFS and ECMWF become somewhat out of phase
across the Southern Plains. However, a general pattern of quasi-
zonal flow with embedded shortwaves suggests seasonable
temperatures with at least a low chance of rain.
Mahale
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 66 88 69 87 / 40 10 30 30
Hobart OK 57 88 68 87 / 10 10 20 30
Wichita Falls TX 67 92 69 90 / 20 10 30 20
Gage OK 49 86 58 87 / 0 0 10 30
Ponca City OK 63 89 69 87 / 60 10 40 40
Durant OK 71 89 69 88 / 20 10 20 10
&&
.OUN Watches/Warnings/Advisories...
OK...None.
TX...None.
&&
$$
11/23/23
Area Forecast Discussion
National Weather Service Pendleton OR
814 PM PDT TUE OCT 4 2016
.UPDATE...Scattered showers are on radar across the CWA. Current
forecast has the showers decreasing around midnight. The latest
NAM and HRRR models are drier than the forecast. Will monitor
radar and satellite trends and may update to decrease pops in
central OR. Rest of forecast on traCK. Coonfield
&&
.PREV DISCUSSION... /issued 430 PM PDT TUE OCT 4 2016/
SHORT TERM...Tonight through Friday...Residual moisture in
westerly flow will contribute to scattered showers tonight
especially over the mountains. There could be a little graupel with
some of the stronger showers this evening. On Wednesday a moderately
strong system will move across the forecast area with the main
energy surge across Oregon. This will result in scattered to
numerous rain showers. Although an isolated lightning strike or two
cannot be ruled out underneath the track of the upper
disturbance...models depict very limited instability. Thus have left
thunderstorms out of the forecast for now. Scattered mainly mountain
showers will continue Wednesday night and early Thursday before
tapering off late Thursday. By Thursday night and especially Friday
a warm front will move across the Washington side of the forecast
area in association with a building upper ridge. This will bring a
chance of rain north. Temperatures will be below normal Wednesday
then return to near normal Thursday and Friday. Snow levels will
start out around 5500 feet tonight then rise to 7000 feet by
Thursday and 8000 feet Friday.
LONG TERM...Friday night through Tuesday...Friday night the
warm front will still be over the northern portion of the forecast
area for showers likely Friday night along the east slopes of the
Washington Cascades and a chance of showers in the northern Blue
Mountains and a slight chance of showers in north central Oregon,
the Lower Columbia Basin and the Grande Ronde Valley. Models are in
fair agreement showing a mid/upper level ridge of high pressure
building and persisting over the Pacific Northwest from daybreak
Saturday through the Tuesday of next week. Model runs have been
consistently showing the ridge day-to-day and run-to-run over the
past several days. As such confidence is fairly high that we are
looking at a static synoptic scale pressure pattern in the mid and
upper layers of the atmosphere for dry conditions at lower
elevations from Saturday into the next work week with a chance of
showers along the east slopes of the central Washington Cascades
each day. Polan
AVIATION...00Z TAFs...VFR conditions will prevail over the next 24
hours. Scattered rain showers will remain over the mountains of NE
Oregon, the Grande Ronde Valley and Wallowa County through this
evening with the showers tapering off and ending overnight. The next
upstream mid/upper low currently SW of Vancouver Island will move
toward the Washington coast over the next 18 hours and usher in
increasing moisture and showers to TAF sites by mid to late
Wednesday morning. showers will begin at KDLS and KDLS by around 09Z
and then spreading to KRDM and KBDN by 12Z and arrive at KPSC by 13Z
and finally begin at KALW by 14Z. Cigs will lower in the vicinity of
the showers starting around daybreak on Wednesday with possible
brief MVFR over the higher terrain. Winds will be 5-15 kts. Polan
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 45 60 43 66 / 20 40 20 10
ALW 49 62 47 67 / 20 30 20 20
PSC 46 63 47 69 / 20 20 10 10
YKM 42 64 41 68 / 20 50 10 10
HRI 45 63 44 69 / 20 40 20 10
ELN 43 62 41 65 / 30 40 20 10
RDM 39 59 35 65 / 30 50 30 10
LGD 39 56 40 60 / 40 50 30 20
GCD 38 54 40 61 / 20 60 40 20
DLS 49 64 47 69 / 50 70 20 10
&&
.PDT Watches/Warnings/Advisories...
OR...None.
WA...None.
&&
$$
76/76/76
Area Forecast Discussion
National Weather Service Blacksburg VA
915 PM EDT Tue Oct 4 2016
.SYNOPSIS...
A wedge of high pressure will remain locked in along the east slopes of
the Appalachians through the end of the week. This will bring a cool
east to northeast breeze and a good amount of clouds, including a
few sprinkles or drizzle mainly along the Blue Ridge, for the next
several days. Hurricane Matthew may track close enough to the region
to bring some gusty winds and heavy rain to portions of Southside
and the Piedmont on Saturday, before a large area of high pressure
builds in with cool, breezy, and dry weather for Sunday.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 850 PM EDT Tuesday...
Satellite showing a few patches of strato-cu remaining under the
inversion this evening otherwise clouds have at least temporarily
mixed out. Latest evening raobs also on the dry side with a very
strong mid level inversion over a shallow moist layer roughly just
above 850 mb. However deep easterly flow remains in place from the
surface to 500 mb, and as the wedge continues to deepen main
question with the degree of low cloud formation after midnight.
Both the latest Nam and HRRR both continue to support low clouds
quickly filling in along the eastern slopes before spreading out
across much of the region by daybreak. Think too dry for much
drizzle at this point but patchy fog possible so leaving out any
precip mention. Otherwise keeping the going forecast for cloud
cover to increase overnight while delaying the onset for a few
hours given current trends and decent temp/dewpoint spreads attm.
Since appears that some spots could cool off quicker before clouds
and increasing northeast flow develop, dropped lows a little
across the region, with most falling into the 50s by dawn.
Previous valid discussion as of 315 PM EDT Tuesday...
Late afternoon satellite imagery shows extensive Cu field across the
region, but the radar does not indicate any showers or sprinkles so we
look to remain dry. Expect the Cu to decrease this evening before a
surge of moisture arrives from the northeast with a resurgence in cloud
cover early tonight. With only a short window for good cooling before
clouds increase again and low level NE flow enhances, conditions do not
favor fog formation. However, some of the hilltops may be in the cloud
layer by morning with reduced visibilities possible. Guidance continues
to indicate the possibility of some sprinkles/spotty drizzle, mainly
along the Blue Ridge, but do not see enough support to stray from a dry
forecast. Expect Wednesday to shape up much like today with expansive
morning clouds gradually giving way to a dry stratocu field. By morning
the NE flow in the piedmont and E/SE flow at the elevations from the
Ridge west should be brisk if not breezy.
Temperatures tonight will be highly sensitive to timing of any clearing
and cloud redevelopment. Believe conditions will not favor valley
locations west of the Ridge bottoming out, so expect lows tonight
generally upper 40s/lower 50s west to mid/upper 50s east. As the cool
wedge strengthens tomorrow looks for below normal readings with highs
near 70 in the east to mid/upper 60s west.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
As of 315 PM EDT Tuesday...
During the first half of this portion of the forecast, a wedge of
high pressure will remain banked up against the lee of the Blue
Ridge. Moisture will be limited in the low levels, while the upper
levels begin to experience increasing moisture associated with the
high level clouds on the north side of Hurricane Matthew.
Precipitation will be limited to some patchy drizzle across the
Northern Mountains of North Carolina and neighboring portions of the
Grayson Highlands of southwest Virginia last Wednesday night into
early Thursday morning.
The high pressure will continue to keep the region dry Thursday
afternoon and early Thursday evening. By Late Thursday night, our
weather pattern will be changing. Moisture on the north side of
Hurricane Matthew is expected to start advecting upslope into the
area. There is a slight chance of light rain along and east of the
crest of the Blue Ridge heading into early Friday morning. During
the day Friday, this moisture fetch will continue to increase, with
light precipitation developing primary across areas along and near
the crest of the Blue Ridge.
For Friday night, the latest forecast from the National Hurricane
Center places the center of Hurricane Matthew right along the east
coast near the NC/SC border late Friday night, early Saturday
morning. Concurrently, and upper trough and associated cold front
will be moving through the Ohio Valley. Precipitation chances are
forecast to increase across the region thanks to the closer position
of Matthew, and also the approach of the cold front. Precipitation
will be the heaviest and the most likely to occur along and east of
a Reidsville, NC to Buckingham, VA line.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 315 PM EDT Tuesday...
The latest official track of Hurricane Matthew has it moving
northeast from its early Saturday morning position near the coast at
the NC/SC border across eastern NC to just off the coast of the
Delmarva Peninsula by Saturday night into early Sunday morning. If
this track holds true, the far southeastern sections of our region
would likely be impacted by a period of heavy rain and gusty winds
during the day Saturday. Some of the sustained wind speeds would be
in the 25 to 30 mph range with gusts approaching 40 mph.
While Matthew is lifting northeast towards the Delmarva Peninsula, a
cold front will enter the western portions of the region and be east
of the area by Sunday morning. Gusty winds are expected in the wake
of this front, with some of the ridge lines and higher peaks
experiencing gusts approaching 40 mph. On Saturday, the western part
of the area will more likely experience light to moderate showers
associated with the front, while eastern sections would experience
moderate to heavy rain associated with Matthew.
By Saturday night, any lingering showers will be associated more
with the passing front as Matthew heads northeast in advance of the
front. The strong winds will help usher notably colder air into the
region.
Cool, dry high pressure will settle over the region by Monday. As
the center draws closer the pressure gradient will slacken and we
will experience a trend towards weaker wind speeds. Dry weather will
continue into Tuesday. The center of the high will shift slightly
east, thus allowing for slightly milder temperatures.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
As of 700 PM EDT Tuesday...
Timing of moisture in the wedge remains the key to this TAF
period as skies have basically cleared early this evening with
loss of heating. This supports continued VFR through much of the
evening before low level moisture attempts to work back in from
the east. Guidance shows this surge of low level moisture
arriving mainly after midnight as the wedge strengthens. Still
appears with light mixing ongoing that there will be enough time
for the development of widespread fog before lower clouds arrive
from the east. Thus, expect TAF sites to be dealing with
IFR/LIFR cigs developing early tonight and persisting into
Wednesday morning, but not as widespread as the current Nam and
likely slower so adjusted a bit.
Expect some of the shallow moisture to be able to mix out and
allow for improvement to MVFR or better Wednesday morning into
early afternoon. The northeast flow at KLYH and KDAN will
increase by daybreak as the wedge deepens with some gustiness to
the character possible as well. Winds at KBLF will exhibit a
similar trend but be from more of a southeasterly direction.
Extended aviation discussion...
Wedge of high pressure along the east side of the Appalachians
may result in sub-VFR conditions into Thursday before the high
shifts farther south and likely returns VFR during Friday.
Hurricane Matthew will threaten the southeast Atlantic Coast by
the end of the week with potential impacts for the Mid- Atlantic
this weekend. No significant influence is expected locally until
Friday night or Saturday at the earliest. Strong northwest winds
along with possible mountain MVFR cigs likely Sunday in the wake
of Mathew offshore and behind a passing cold front.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...None.
NC...None.
WV...None.
&&
$$
SYNOPSIS...MBS
NEAR TERM...JH/MBS
SHORT TERM...DS
LONG TERM...DS
AVIATION...JH/MBS/PM
Area Forecast Discussion
National Weather Service Shreveport LA
922 PM CDT Tue Oct 4 2016
.UPDATE...
Shortwave energy passing well to our north and west so far this
evening. Newest progs including the HRRR want to keep this
activity well northwest of our region overnight and for this
reason...have lowered pops to slight chance variety and trimmed
this pop back to our extreme northwest zones for the remainder of
the night. Isolated showers which had moved into our southeast
zones earlier this evening have dissipated so no need to add a pop
into this area as this was tied to a weak seabreeze boundary.
Increasing southerly flow in the low levels of the atmosphere
should result in increasing stratocumulus deck developing after
midnight and moving into our region from the south. Have added
cloud cover after midnight and through the morning hours on Wed
for all but our eastern most zones.
Fcst min temps are in the ballpark but temps were very close to
fcst min temps across our eastern and northeast zones so for that
reason...lowered these temps a degree or two for the remainder of
the night.
All other grids are in good shape...thus...no further changes were
necessary.
Updated fcst package out shortly...13.
&&
.PREV DISCUSSION... /issued 739 PM CDT Tue Oct 4 2016/
AVIATION...
For the 05/00Z TAFs, VFR conditions to prevail through much of the
overnight hours before low ceilings and patchy fog develop across
our terminal sites. MVFR/IFR conditions will likely occur as early
as 05/09Z and persist through the remainder of the morning hours
with ceilings slowly lifting into the midday timeframe. Expect VFR
conditions to return by 05/18Z at all sites, possibly earlier with
increased BL mixing and heating. Winds will remain S/SE, generally
between 5-10 kts through the period except at MLU where periods of
calm winds may occur overnight. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 70 90 68 91 / 10 10 10 10
MLU 67 91 65 91 / 10 10 0 0
DEQ 65 88 66 89 / 20 10 10 10
TXK 69 89 67 90 / 10 10 10 10
ELD 66 89 64 89 / 10 10 10 10
TYR 71 90 70 90 / 10 10 10 10
GGG 70 90 68 90 / 10 10 10 10
LFK 71 91 69 91 / 10 20 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...None.
LA...None.
OK...None.
TX...None.
&&
$$
19/13
Area Forecast Discussion
National Weather Service Grand Forks ND
324 AM CDT Wed Oct 5 2016
.SHORT TERM...(Today and tonight)
Issued at 324 AM CDT Wed Oct 5 2016
With pcpn coverage rapidly decreasing early this morning, the main
forecast challenge will shift to overnight low temps. Depending on
wind speeds and cloud trends, there could be a freeze Friday
and/or Saturday morning. As of early this morning the remaining
band of rain was located over the Thief River Falls to Park Rapids
area, moving rapidly northward. With the 50 to 60 knot low level
jet, this activity should exit the FA around sunrise, which is
supported by the latest HRRR runs. There may be a few breaks in
the clouds this morning, but more clouds will be moving in from
the west. There will also be increasing winds again, this time
from the SW to W.
Currently looks like it could get close to wind advisory criteria
over the higher terrain west of the Red River Valley this
afternoon, but the window may only be for a few hours before they
decrease again in the early evening. Winds speeds stay up tonight
along with some cloud cover, but low temps will still be a
challenge. Guidance shows lows across a good portion of the FA
dropping into the low to mid 30s. This is in the frost range,
although with wind speeds staying up, there will probably not be
any actual frost formation. There could be some very light rain
across the Devils Lake area by afternoon or along the Canadian
border tonight, but overall this would be pretty minimal. Doubt
any flakes of snow would mix in, but there is a low potential.
.LONG TERM...(Thursday through Tuesday)
Issued at 324 AM CDT Wed Oct 5 2016
This will remain the main forecast issue Thursday through Friday
night. Chances for any significant pcpn looks minimal, so the
main thing will be clouds and wind speeds. Forecasting some temps
around 30F Thursday night west of the Red River Valley and for
more of the FA Friday night. Therefore depending on clouds and
wind speeds, there is a potential for a freeze on one or both of
these nights.
Saturday to Tuesday has good agreement in model runs with 500mb flow
starting from the northwest and becoming zonal for the first part of
next week. Overall a dry period with low chance of PoPs on Sunday
morning across the north and again Tuesday with a short wave
approaching. Cool temperatures to start will moderate some from
upper 40s to near 50 on Saturday to upper 50s to near 60 by Tuesday
with lows rising from around freezing Saturday morning to lows
around 40 for by Tuesday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1140 PM CDT Tue Oct 4 2016
The MVFR cigs GFK/FAR area has now shifted east at 05z Tue and
will see a low level dry slot over E ND and the RRV overnight into
Tuesday morning before some stratocu move in from the west Tuesday
daytime...first reaching DVL but taking a while to reach GFK and
especially Fargo. MVFR cigs a while longer TVF before VFR later
tonight and MVFR cigs into Bemidji with rain then VFR for a time
Tuesday. Winds a bit calmer south-southeast then turning west to
southwest in E ND Tuesday and increasing in speed west of the RRV
Tuesday aftn to 15-30kts.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
SHORT TERM...Godon
LONG TERM...Godon/JK
AVIATION...Riddle
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
259 AM CDT Wed Oct 5 2016
.SHORT TERM...
252 AM CDT
Through Thursday night...
Increasing chances for occasional showers or storms over the next
few days, and timing the highest coverage is the focus of the
short term forecast, along with the above normal temps.
Things are quiet initially this morning with some increasing
clouds and southeast flow. Upper low pressure over the far
northern plains is resulting in moist southwest flow across the
central plains and just to our west this morning. Regional radar
mosaic depicts a complex of showers and thunderstorms that on the
southern fringe have generally been weakening/shrinking in
coveargeas instability wanes and also being removed from the main
forcing to the north, but a stout LLJ continues to feed into and
ahead of the front across the plains. The LLJ will weaken veer
overnight shifting the moisture transport axis towards our area,
but it will be in a much weaker state. There could be a few
showers in the morning as a lead shortwave and weak moisture
transport slides through, but many guidance sources are mostly
dry. As the occluding front continues eastward, there could be
enough forcing for a few showers or storms, especially from
Chicago eastward, mainly in the afternoon. Have some pops in today
to lend some credence to the 4km NAM but the RAP and both HRRRs
are dry. Cloud cover early will initialy slow the warmup but highs
back well into the 70s to near 80 are a good bet today.
Things get a bit more muddled tonight as the upper level jet strengthens
to our northwest, the moist LLJ (right from the Gulf) ramps up to
our southwest, south of a now slightly stalled out warm frontal
boundary across the central plains and extending into
Missouri/southern IA. A warm and moist airmass will exist behind
this front. The bulk of guidance really keeps forcing overnight
focus west of the area closer to the upper forcing, and southwest
closer to the warm front. The front is forecast to lift northward
to some degree late tonight into Thursday morning ahead of upper
forcing to the west and a ramp up of the low level jet. While some
precip is possible overnight, and even suggested by the NAM and
several other Hi-res models, the better chance at this time
appears to be late tonight into the morning as the front lifts
with the LLJ, and have carried chance pops for many areas, highest
W-S, though confidence on this time frame is not overly high on
what coverage will look like.
A secondary shortwave along the base of the upper trough will swing
northeast into Iowa Thursday afternoon, and additional organized
convection will initiate. Cyclogenesis continues as the low
strengthens as it shifts into WI and toward Lake Superior tonight.
Some showers are possible through the day as the front lifts
through the area, with the axis of stronger activity getting close
to the area in the evening. Enough forcing slides in later this
evening and overnight to support this activity getting into NW and
portions of NC Illinois, though a weakening trend is noted in
model QPF fields.
KMD
&&
.LONG TERM...
252 AM CDT
Friday through Tuesday...
Remarkably, model agreement on the Friday through the weekend period
has improved dramatically from 24 hours ago at this point. Both
the Canadian and GEM have shifted into the ECMWF camp. The theme
of the forecast has not changed with our transition back to cooler
weather for the weekend, but the degree of cold appears to be
tempered a bit. If this guidance shift towards the EC is correct,
the cold front will arrive at our western CWA by daybreak Friday,
if not sooner per the EC., then cruise southeast through the area
on Friday. There may be some decaying showers from the convective
complex to our west overnight into Friday morning, but then it
things turn cooler and initially breezy for the rest of Friday
with significant drying occurring behind the front.
Deep high pressure extending from the Canadian prairies and into
central plains will build over the Great Lakes region Saturday, then
shift to the eastern Great Lakes Sunday. and the weekend will be
dry, making for an initially cool but dry weekend. The high will
move east Sunday, and breezy southwest winds will make for another
mild and mostly sunny/partly cloudy afternoon. Broad southwest
flow into early next week will keep conditions mild with some
smaller chance for precip.
For those with interests on the east coast, the implications of
the upper level energy with this front cruising quickly to the
east this weekend is a vastly different track to Hurricane Matthew
after its initial impacts on Florida and the Carolinas during the
weekend, with guidance no longer bringing the tropical system up
the east coast early next week. Spread with this system beyond the
near term is very large. For more information, read WPC`s PMDEPD
long range model discussion and the NHC 5 day forecast.
KMD
&&
.AVIATION...
For the 06Z TAFs...
There are no significant weather concerns during the day today.
However, gusty south-southwesterly winds are expected during the
day, along with a small threat of a shower and or thunderstorm
this afternoon.
No major changes were made with the 06z TAFs other than to push
the VCSH mention off until after 18z at the Chicago area
terminals. It appears the morning should remain precip free,
though south-southwesterly winds will likely become gusty up
around 20 KT by mid to late morning. This afternoon an upper
level disturbance is expected to shift northeastward from IA into
WI, and this will likely help focus some showers and possibly a
few storms today. However, given the northeastward trajectory of
this disturbance, it appears the best focus for these showers and
storms today will largely be north of the area in WI. Given this
potential, I felt it prudent not to mention anything more than a
VCSH at this time.
A second weather disturbance is expected to shift over the Central
Rockies tonight. As this occurs, it appears that a stronger
northward flux of moisture may set the stage for overnight
showers and thunderstorms, especially over portions of northern
MO, southern IA and adjacent sections of western IL. Confidence
is low on how far east towards the Chicago area terminals these
storms may get by daybreak Thursday, but we cant rule out the
possibility at this point. However, with low confidence, I have
left the extend portion of the KORD TAF dry at this time.
KJB
&&
.MARINE...
231 AM CDT
Strong pressure falls, associated with low pressure over southern
Manitoba, have been overspreading the Upper-Midwest overnight and
resulting in some stout southeasterly winds over the open waters
of Lake Michigan. In fact, many marine observing sites, including
the open water buoys have been reporting gusts of 25 to 30 KT over
the past couple hours. These winds will continue today, but will
gradually become southerly this afternoon. Winds will then begin
to weaken this evening as the surface gradient abates over the
lake. Expect these lighter southerly winds to continue into
Thursday. Strong southerly winds (up around 30 KT) are expected to
make a return though by Thursday night into early Friday as
another storm system rapidly shifts northeastward from the Central
Plains towards the Western Lakes Region. The low will then drive a
cold front eastward over the lake Friday, with a period of gusty
west-northwesterly winds likely in its wake. These northwesterly
winds should gradually ease this weekend as a surface ridge of
high pressure builds in over the the Southern Lakes Region.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Memphis TN
225 AM CDT Wed Oct 5 2016
.DISCUSSION...
An upper ridge will continue to dominate the forecast over the
next seven days. Currently, skies are clear across the Mid-South.
Looking at latest radar and satellite images, a line of showers
and thunderstorms that developed earlier in the evening across
Kansas and Oklahoma has pushed east into Southwest Missouri and
Northwest Arkansas. The latest HRRR has the line dying out before
it reaches Northeast Arkansas. However, several other models
including the NAM and GFS have the line reaching Northeast
Arkansas later this morning. As a result, have left small POPS for
Northeast Arkansas and the Missouri Bootheel today. This may
actually be the best chance for rain that the area will have over
the next seven days.
After today, the only POPS that are in the forecast are for Friday
afternoon for Northeast Arkansas and the Missouri Bootheel ahead
of a cold front. However, the chances are rather slim as models
are showing whatever convection that develops ahead of the front
to quickly dissipate as the front pushes into the Mid-South due to
the dry air in place.
Thus, above normal temperatures and dry conditions will prevail
through Friday. Highs will range in the mid 80s to lower 90s.
Lows will drop off into the 50s at night thanks to the dry air in
place. Once the cold front pushes through the area Friday Night,
highs will drop back into the 70s. Although the upper ridge will
quickly begin to rebuild over the region by the latter part of the
weekend resulting in highs creeping back into the 80s for the
beginning of next week.
The biggest weather concern for the week may be with fire weather.
The drought remains ongoing across North Mississippi. With the
dry air in place, relative humidity values will drop below 30
percent almost everyday creating elevated fire danger over much of
the upcoming week. Saturday may be particularly dangerous as gusty
winds behind the cold front could potentially cause a rare red
flag event. Fire weather partners will need to stay tuned to the
latest fire weather forecasts.
KRM
&&
.AVIATION...
/06z TAFs/
Generally VFR conditions are anticipated overnight beneath mostly
clear skies and light southeast winds. High clouds are expected to
increase late, but rain chances remain low. If any showers make
it into the CWA from the west early Wednesday morning, KJBR is
really the only terminal that may be affected. That said, its a
very low probability event. Otherwise, expect south winds of 7-9
kts Wednesday afternoon.
Johnson
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
Area Forecast Discussion
National Weather Service Medford OR
228 AM PDT WED OCT 5 2016
.DISCUSSION...A well-defined trough will move through the
forecast area today from the northwest and will bring a period of
enhanced shower activity. Morning infrared satellite imagery shows
the trough reaching the coast now, bringing rainfall to coastal
counties. Other areas are measuring rainfall this morning too, due
to continued deep onshore flow in a rather moist and unstable air
mass.
A few elements could come together today to bring thunderstorms and
gusty winds to portions of the West Side. Noting a healthy wind
profile with 0-6km bulk shear values 30kt+ and 25-30kt of southwest
to west winds from 700mb down to the surface, gusty winds could
certainly accompany any thunderstorms that form today. Additionally,
instability has trended higher compared to yesterday`s models for
areas west of the Cascades, and the HRRR has been consistent in
showing a group of thunderstorms progressing from the coast inland
this morning. Surface heating will be minimal this morning, so
confidence is low on significant thunderstorm activity, but we have
changed wording to coverage (isolated) to show increasing confidence
based on the latest data. Day shift will monitor 12Z model runs to
see if instability progresses east of the Cascades this afternoon,
and thunderstorms could be added to the forecast there if needed.
Elsewhere, a solid inch+ of rainfall is expected near the Curry
County coast. Also, up to 5 inches of wet snow is possible at the
Crater Lake rim, where snow levels are expected to be around 6000
feet and favorable deep layer westerly winds will optimize
orographic lift today. Travel impacts are expected to be minimal
based on the high snow levels, but morning road surface
temperatures in the mountains are in the 30s, and be prepared for
perhaps some morning slushy conditions on the very highest
mountain roads.
Thursday should be dry and warmer over the forecast area under low
amplitude ridging. Thursday night into Friday morning a weak
disturbance will scrape the coast and Umpqua Basin with a slight
chance for light rain then push northward, leaving Friday afternoon
into Sunday dry and warm, with temperatures nudging above normal by
a few degrees this weekend. Models have been waffling some with the
Thursday night system so confidence is low on actual rain amounts
and chances of precipitation, but impacts will be relatively low
with this rather weak system. We have introduced some patchy fog in
the Umpqua Valley Saturday morning to account for upper ridging,
expected clear skies aloft, and climatology that indicates the
season for fog in Roseburg in approaching, especially after recent
rainfall.
A more active weather pattern is expected by the middle of next
week. Atmospheric River confidence tools are showing increasing potential
for some moderate to strong AR events during week 2, and the
CFSv2 model suggests the same.
&&
.AVIATION...05/06Z TAF CYCLE...Expect a mix of VFR and MVFR CIGS
through today, with MVFR and terrain obscuration most prevalent
from the coast to the Cascades where showers will be numerous to
widespread. Isolated thunderstorms are possible through today and
especially this morning, mainly north and west of the Umpqua
Divide. Showers will be isolated to scattered east of the
Cascades.
Note: The ceilometer at FAA site KOTH is out of service, so there
will be no ceiling observations available generally between the
hours of 04Z and 14Z.
&&
.MARINE...Updated 1030 PM PDT Tuesday, October 4, 2016...
Northwest swell will continue to build over the marine waters
through the day as a storm system drops southeastward through the
northeast Pacific. Nearshore buoys are already indicating
significant wave heights of 10-12 feet in the coastal waters. An
offshore buoy (46005) right under the main storm has been showing
seas of 20-21 feet this afternoon. Decayed swell into our waters
peaks at 14-16 feet across NW sections, especially PZZ370. For
this reason, have issued a hazardous seas warning through today.
The rest of the area will have seas hazardous to small craft. Seas
gradually subside below 10 feet by Thursday morning. A frontal
system may graze the area Thursday night into Friday, then high
pressure will build in late this week into this weekend.
Spilde/Sven
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...None.
CA...None.
Pacific Coastal Waters...Small Craft Advisory for hazardous seas until 5 AM PDT Thursday
for PZZ350-356-370-376.
Hazardous Seas Warning until 5 PM PDT this afternoon for
PZZ370-376.
$$
NSK/NSK/SBN
Area Forecast Discussion
National Weather Service Marquette MI
455 AM EDT Wed Oct 5 2016
.SHORT TERM...(Today and tonight)
Issued at 455 AM EDT WED OCT 5 2016
Water vapor imagery and RAP analysis show a broad trof covering much
of the w half of the CONUS with vigorous shortwave/mid level low
centered over the MT/ND/Saskatchewan border. Shortwave trof
extending from this feature and pivoting ne thru the plains is
supporting a relatively narrow band of shra/embedded thunder from MN
s thru Missouri. Over Upper MI, it`s been an unseasonably warm night
under a moist airmass and southerly winds. Current temps are near
normal max temps for this time of year...around 20 degrees above
normal.
Models remain in good agreement on fcst details today/tonight.
Shortwave trof currently pivoting ne across the Plains will lift
across the Upper Great Lakes today, propelling sfc cold front across
the fcst area. Given abundant column moisture with precipitable
water around 1.3 inches/more than 200pct of normal and decent deep
layer forcing, expect the relatively narrow band of shra/embedded
thunder currently moving into the Upper Mississippi Valley to hold
together and sweep across the area today, giving most locations
roughly a 2-3hr period of steadier pcpn. There may be some narrowing
of the pcpn area and a breakdown of a solid band of shra toward a
band of sct/nmrs shra with time as convergence along cold front and
deep layer forcing begin to weaken. Avbl instability supports some
embedded thunder, and not out of the question that tstm coverage may
increase a bit with front moving across the central and eastern fcst
area during the more favorable time of the diurnal cycle. Rather
sharp deep layer q-vector divergence/drying behind cold front will
bring a quick end to pcpn along with clearing skies from w to e late
aftn and evening. However, with limited CAA allowing nocturnal
inversion development, drying of the lowest levels may not be
sufficient to avoid development or persistence of low clouds over
the eastern fcst area tonight. Fog could develop as well.
As for temps, despite clouds/shra, another unseasonably warm day is
expected given the unseasonably warm start to the day. Expect high
temps in the mid 60s to lower 70s. Drier air mass, clear to partly
cloudy skies and diminishing winds will allow temps to fall back to
the mid 40s to lwr 50s tonight...still about 10 degrees above normal
for early Oct.
.LONG TERM...(Thursday through Tuesday)
Issued at 328 AM EDT WED OCT 5 2016
Thu wl be another warm day before an aprchg disturbance/lo pres
bring some wdsprd showers on Thu ngt into Fri. Cooler and drier air
wl follow the passage of this disturbance/lo pres into Ontario. An
aprchg disturbance/some deeper mstr over a lk induced trof that
dvlps over the relatively warm lk waters may result in some lk
effect showers on Sat before an aprchg hi pres brings a drying
trend. A fast zonal flow dominating late in the weekend/the first
half of next week wl support a changeable wx pattern along with
above normal temps.
Thu...While Thu wl at least start on the quiet side under lingering
mid lvl dry air in the wake of the Wed pcpn event, some of the
guidance, particularly the 12Z ECMWF, generate some pcpn during the
aftn over mainly the se cwa as a weak shrtwv rides newd parallel to
the stalled fnt and within the sw flow alf btwn persistent upr rdg
over the se ConUS and upr trof axis over the Rockies. Since this
scenario is not unreasonable considering the rather hi amplitude upr
pattern in place, wl retain some chc pops in the aftn over the se
cwa. Although the nw cwa wl remain dry, expect some incrsg clds even
there ahead of a stronger shrtwv lifting newd into central Plains.
Even if there are more clds over the se that would limit the diurnal
temp rise there, fcst h85 temps within a few degrees of 10C indicate
another unseasonably warm day is in store. If and where there is
more sunshine, temps could rise aoa 70.
Thu ngt/Fri...While the models are in fairly good agreement showing
the Plains shrtwv wl ride newd within the sw flow alf thru the Upr
Lks on Thu ngt and into Ontario on Fri, the guidance varies on the
intensity and thus the track of the accompanying sfc lo pres. Recent
ECWMF runs have shown a deeper sfc lo pres tracking farther to the
w, with most of the cwa falling into the warm sector. The models
that show a weaker sfc lo pres like the 00Z GFS indicate all but the
ern cwa wl be on the cooler wrn side of the fnt/weaker lo pres
track. Despite these differences, a period of vigorous dpva/deep lyr
qvector cnvgc/ upr dvgc with pwat as hi as 1.50 inch over at least
the se cwa wl support hi likely/categorical pops and a period of mdt-
heavy rain/ perhaps a TS. The guidance has come into better
agreement showing more vigorous drying/mid lvl subsidence by Fri
aftn under the jet surge region in the wake of the shrtwv/sfc lo
pres lifting into Ontario and attendant cold fropa. As h85 temps
fall toward about -2C by late in the day over the w, Fri wl turn
much cooler than on Thu.
Fri ngt/Sat...Although there wl be some drying in the initially acyc
wnw flow in the wake of the departing lo pres on Fri ngt, an aprchg
shrtwv/some deeper mstr/h85 thermal trof within a few degrees of -3C
over the relatively warm waters of Lk Sup are fcst to initiate some
lk induced troffing and at least sct showers over mainly nrn Upr MI
late Fri ngt thru much of Sat. A shrtwv rdg/larger scale subsidence
following the shrtwv wl bring a drying trend by late Sat. Temps over
the interior scentral could turn rather chilly on Fri ngt, but a
steady wnw flow with h925 winds up to 25 kts should limit the
diurnal temp fall a bit.
Later weekend...Although the models differ on timing within a fairly
tight wnw flow alf Sat ngt/Sun, sfc hi pres trailing the departing
shrtwv is fcst to slide acrs the Upr Lks sometime during this
period. If the hi pres/mid lvl dry air are ovhd Sat ngt, the overngt
could be rather chilly. But the faster 00Z GFS shows some waa clds
overspreading the area on Sat ngt as the hi pres exits to the e and
a quick moving shrtwv riding along the Cndn border aprchs.
Considering the fast wnw flow dvlpg near the Cndn border, suspect
the quicker GFS might be on the right track.
Early next week...Not surprisingly with a zonal flow, model
differences remain quite pronounced next week with quick moving
disturbances embedded in this fast flow. In general, since hgts wl
be well above normal, expect above normal temps to prevail even
though a cool fnt in the wake of one of these passing disturbances
could drift thru the Upr Lks at some point during this time
accompanied by some sct showers.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 140 AM EDT WED OCT 5 2016
Expect VFR conditions to continue at all sites overnight, but then
cigs will begin to lower toward MVFR this morning with advance of
frontal system and associated band of showers from Plains. However,
given the upslope flow at KSAW, not out of the question that IFR cigs
could occur at times during the night. Conditions will return to VFR
at all sites in the afternoon after the front passes.
&&
.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 455 AM EDT WED OCT 5 2016
Ahead of a cold front sweeping across Lake Superior today thru early
this evening, SE to S winds up to 20-30kt are expected, strongest
over the central and east part of the lake. While SW winds as high
as 20-30kt should occur behind the front tonight into Thu morning,
strongest between Isle Royale and the Keweenaw Peninsula, the
pressure gradient and winds will weaken for a time Thu aftn and
night as a low pressure trough develops over the Upper Lakes ahead
of a low pressure wave developing over the southern Plains. After
this low pressure wave passes late Thu night/early Fri morning, NW
winds up to 30kt will develop on Fri, strongest over the e half of
Lake Superior. NW winds up to 20kt will linger into Sat before
diminishing to under 15kt late Sat into Sun as high pres arrives.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Rolfson
LONG TERM...KC
AVIATION...07
MARINE...Rolfson
Area Forecast Discussion
National Weather Service Paducah KY
331 AM CDT WED OCT 5 2016
.SHORT TERM...(Today through Friday night)
Issued at 331 AM CDT Wed Oct 5 2016
All eyes are to the west where a band of convection is attempting
to push eastward through central and southwest Missouri. With the
stronger thunderstorms propagating southeast toward Arkansas, we
may not see much thunder with this activity as it moves into our
far western counties around or just prior to sunrise.
The latest HRRR and WRF runs continue to show scattered convection
moving into the area, but gradually diminish it as it moves
eastward through southeast Missouri and southern Illinois through
midday. They show very little convection left through the
afternoon and do not bring it into Kentucky or Indiana. Will
continue with chancy PoPs on the western border tapering to no PoP
in Kentucky and Indiana, mainly this morning, with only slight
chances in the afternoon.
The 00Z model consensus builds the upper ridge back over the
region, and allows the surface ridge to poke back into the area
for tonight into early Friday. The models try to push the main
upper trough through the region along with a cold front Friday and
Friday night, but with the ridging over the East Coast and
Southeast, the cold front basically dissipates, resulting in a
surge of surface high pressure through the area Friday afternoon
and night. Any convection associated with the approaching cold
front is expected to dissipate before reaching the area Friday.
As for temperatures, it will continue to be hot through the
period. High temperatures will be around 10 degrees above normal
today and Thursday, and may not be far from it on Friday depending
on cloud cover and timing of the high pressure surge. Thursday
will be the hottest day with upper 80s to 90 not out of the
question. Lows will be quite mild around 10-15 degrees above
normal tonight and Thursday night. Lows will trend down near
normal levels Friday night with the fresh surface high pressure
building over the region.
.LONG TERM...(Saturday through Tuesday)
Issued at 331 AM CDT Wed Oct 5 2016
Above average confidence in much of the extended period due to
operational deterministic and probabilistic model agreement in the
general synoptic pattern for our region.
The past few runs of the operational models have been continually
drier for the cold frontal passage into Saturday. As a much drier
and cooler air mass enters the mid Mississippi valley behind the
front, our typical moisture flow from the Gulf is blocked by upper
level ridging west of Hurricane Matthew. Thus, a dry and
pleasant forecast through Tuesday for this update.
The main uncertainty in the extended forecast develops starting
Tuesday when a series of upper level shortwave disturbances begin to
disrupt the Midwest. The latest 00z runs of the GFS/Euro/GEFS mean
show Matthew stalling east of Florida, which essentially prevents
most significant Gulf moisture from returning to our area and
results in rain chances remaining to our north and west. However,
most of the previous model guidance showed Hurricane Matthew
meandering out to sea, allowing for some rain chances mid week. Will
be interesting to monitor this progression over the next week.
For Friday night into Saturday, we will see a big drop from
temperatures above normal, down to slightly below seasonal normal
temps for the weekend. Highs on Saturday will reach the lower 60s to
near 70, and the overnight low early Sunday will bottom out in the
mid 40s. For early next week, daytime highs warm into the mid to
upper 70s, with lows in the low to mid 50s.
&&
.AVIATION...
Issued at 1020 PM CDT Tue Oct 4 2016
The latest model runs are indicated less clouds than previous runs
with VFR for all sites through the valid time at all sites. There
will likely be a low deck develop during the heating of the day
Wednesday but should be short lived. There will be southerly wind
Wednesday with some gusts into the teens at KEVV and KOWB during
the daylight hours.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
SHORT TERM...DRS
LONG TERM...BP2
AVIATION...KH
Area Forecast Discussion
National Weather Service Bismarck ND
1053 AM CDT Wed Oct 5 2016
.UPDATE...
Issued at 1048 AM CDT Wed Oct 5 2016
After seeing the new NAM, looking at the latest bufkit HRRR
soundings, coordinating with surrounding offices and peeking out
the window, have decided to extend the wind advisory eastward
through south central ND. Good mixing with 40-45 knots at the top
of the boundary level through the afternoon. Looks to remain
breezy to windy tonight for maybe the eastern half of the advisory
but for now will leave the expiration time alone and can revisit
this afternoon.
UPDATE Issued at 957 AM CDT Wed Oct 5 2016
Surface and upper level low pressure continues to spin over
southeast Saskatchewan, and are forecast to move slowly east into
Manitoba today. This will bring scattered rain and snow showers to
western and far north central ND this morning. Subsidence over
south central ND into the JRV this morning but as a vort lobe
drops southeast behind the exiting low this afternoon, we may see
scattered showers extend into the south central. We did extend the
slight chance pops a little farther south, to around Bismarck and
Mandan to around Harvey this afternoon. Only trace amounts are
expected.
Current wind advisory looks good with sustained winds already
around 30 mph. Will need to monitor for possibly extending this a
little farther east as Latest mesoscale bufkit soundings indicate
possible wind advisory winds east into the south central portion
of the state.
UPDATE Issued at 635 AM CDT Wed Oct 5 2016
Current forecast trending ok. Latest satellite and radar loops
show the main area of precipitation hanging back to teh west and
northwest of the region. This will limit the chance of rain and
snow to the far west and northwest.
&&
.SHORT TERM...(Today and tonight)
Issued at 408 AM CDT Wed Oct 5 2016
Main forecast issues involve mixed precip across the west and north
related to deep vertically stacked low pressure system that will
slowly depart the region today with strong winds continuing behind
the system. Will also have good potential for near to below
freezing temperatures Wednesday and particularly Thursday night
with widespread 20s likely for min temperatures over much of our
area Thursday night/Friday morning.
Latest satellite imagery, surface obs and radar show low pressure
centered over extreme northwest ND with wrap-around mixed precip
over eastern Montana and slowly moving into ND. Beach reported light
snow earlier, although so far precip type has been mainly liquid
with temps in the upper 30s. High resolution models continue to
spread the precip into the state with colder air on the backside of
the system supporting a mix or changeover to snow. Latest model
iterations have backed off on the changeover to snow. Any
accumulations should be very light.
Winds have been strongest across the southwest part of the state
overnight, with sustained winds around 30 mph at KDIK. GFS
continues to be a bit of an outlier on the stronger side of
forecast winds, but even the weaker NAM winds show 30 knot
boundary layer winds at KDIK and mid 40kt values at top of the
mixed layer per BUFKIT data. Leaned toward higher end of wind
forecast guidance using CONSMOS, which supports wind advisory
criteria across the southwest. It looks to be more marginal across
Grant and Sioux counties, but included them in the advisory as
well, with a slightly later starting time. Winds should ease up by
late afternoon/early evening.
Cold advection today and tonight will drop 850 mb temperatures
over ND to -6C north to -2C across the south. Current min temp
forecast for tonight has low temps around 30 F across the west to
low 30s east, which barring any changes in the forecast will
likely prompt a freeze warning.
.LONG TERM...(Thursday through Tuesday)
Issued at 408 AM CDT Wed Oct 5 2016
The coldest temps of the season will highlight the remainder of
the week as the low pressure system continues to slowly move away
from the area with a ridge of high pressure building in by Friday.
The associated surface ridge nudges into western ND Thursday night
with 850 mb temps lowering slightly with the -6C isotherm nudging
into central ND. Forecast minimum temperatures drop well into the
20s F Thursday night/Friday morning. The upper ridge continues to
move over the Northern Plains on Friday with more of a quasi-
zonal upper level flow setting up, which will support moderating
temperatures and mostly dry weather. High temps initially in the
40s Thursday and Friday will reach the 50s and 60s by Sunday and
continue into early next week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1048 AM CDT Wed Oct 5 2016
Surface low pressure centered in southeast Saskatchewan is forecast
to move slowly northeast Wednesday. A cold northwest airflow will
bring widespread MVFR conditions across west and central North
Dakota impacting KISN-KDIK-KMOT-KBIS-KJMS. Latest trends suggest
less precipitation across the northwest so have removed the lower
visibilities in snow for KISN.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 7 PM CDT /6 PM MDT/ this evening for
NDZ018>023-025-031>037-040>048-050-051.
&&
$$
UPDATE...TWH
SHORT TERM...JNS
LONG TERM...JNS
AVIATION...JV/TWH
Area Forecast Discussion
National Weather Service Grand Forks ND
1056 AM CDT Wed Oct 5 2016
.UPDATE...
Issued at 1052 AM CDT Wed Oct 5 2016
Wind speeds along the James and Sheyenne valleys continue to
increase this morning and expected to increase more this afternoon
as mixing increases throughout the boundary layer. Expect Valley
City area to soon see sustained 30 mph winds which will continue
through early evening. Will issue Wind Advisory from Eddy down to
Sargent county (including Steele) while keeping the valley out of
the advisory due to local effects with westerly winds.
UPDATE Issued at 957 AM CDT Wed Oct 5 2016
Overall forecast is in good shape however some wind gusts along
the western edges of forested areas in eastern zones are gusting
earlier than anticipated. Will make adjustments to wind gusts
generally increasing gust spread 5 to 10 knots.
UPDATE Issued at 708 AM CDT Wed Oct 5 2016
Echoes on radar are rapidly moving northward and should exit the
FA in the next hour. Winds are already increasing and will be
gusty through the day and early evening. There may be a few breaks
of sun today, especially across the south, but overall more clouds
than sun.
&&
.SHORT TERM...(Today and tonight)
Issued at 324 AM CDT Wed Oct 5 2016
With pcpn coverage rapidly decreasing early this morning, the main
forecast challenge will shift to overnight low temps. Depending on
wind speeds and cloud trends, there could be a freeze Friday
and/or Saturday morning. As of early this morning the remaining
band of rain was located over the Thief River Falls to Park Rapids
area, moving rapidly northward. With the 50 to 60 knot low level
jet, this activity should exit the FA around sunrise, which is
supported by the latest HRRR runs. There may be a few breaks in
the clouds this morning, but more clouds will be moving in from
the west. There will also be increasing winds again, this time
from the SW to W.
Currently looks like it could get close to wind advisory criteria
over the higher terrain west of the Red River Valley this
afternoon, but the window may only be for a few hours before they
decrease again in the early evening. Winds speeds stay up tonight
along with some cloud cover, but low temps will still be a
challenge. Guidance shows lows across a good portion of the FA
dropping into the low to mid 30s. This is in the frost range,
although with wind speeds staying up, there will probably not be
any actual frost formation. There could be some very light rain
across the Devils Lake area by afternoon or along the Canadian
border tonight, but overall this would be pretty minimal. Doubt
any flakes of snow would mix in, but there is a low potential.
.LONG TERM...(Thursday through Tuesday)
Issued at 324 AM CDT Wed Oct 5 2016
This will remain the main forecast issue Thursday through Friday
night. Chances for any significant pcpn looks minimal, so the
main thing will be clouds and wind speeds. Forecasting some temps
around 30F Thursday night west of the Red River Valley and for
more of the FA Friday night. Therefore depending on clouds and
wind speeds, there is a potential for a freeze on one or both of
these nights.
Saturday to Tuesday has good agreement in model runs with 500mb flow
starting from the northwest and becoming zonal for the first part of
next week. Overall a dry period with low chance of PoPs on Sunday
morning across the north and again Tuesday with a short wave
approaching. Cool temperatures to start will moderate some from
upper 40s to near 50 on Saturday to upper 50s to near 60 by Tuesday
with lows rising from around freezing Saturday morning to lows
around 40 for by Tuesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 957 AM CDT Wed Oct 5 2016
Mid morning amendments to address sky/cigs in the east and wind
gusts at BJI. Also will increase wind gust spread at all sites and
bring them in earlier than expected.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Wind Advisory until 7 PM CDT this evening for NDZ024-028-029-038-
049-052.
MN...None.
&&
$$
UPDATE...Speicher
SHORT TERM...Godon
LONG TERM...Godon/JK
AVIATION...Speicher
Area Forecast Discussion
National Weather Service Wilmington NC
1202 PM EDT Wed Oct 5 2016
.SYNOPSIS...
Strong high pressure will build from the north through the mid
week period. The center of the high will slide well offshore
from the NE states, allowing Hurricane Matthew to move northward
through the Bahamas Wednesday and up the Southeast U.S. Coast
Thursday through the weekend. Cool high pressure will build
across the area from the west early next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 1202 PM Wednesday...No significant changes to the forecast
with the midday updates, with NE breezes, plentiful clouds, and
maximum temperatures held in check to near near normal for this
time of year. Very little measurable rainfall is anticipated this
afternoon and tonight, only trace amounts for the most part. The
previous discussion follows.
KLTX Vad Wind Profiler registering 25-35 KT in the lowest few
thousand feet as the low-level pressure gradient tightens due to a
high pressure wedge strengthening through the western Carolinas.
Gusts of 20 to 30 mph along area beaches will remain fairly common
this afternoon through tonight. Elevated humidity in the lowest
5000 feet and weak convergence offshore will allow periodic light
rain near the coast, and favored slightly north of Cape Fear
today. Very little however expected in the QPF department, as
occasional sprinkles and spritzes are the primary expectation.
Maximums appear on target given the extensive cloud cover poised
to remain in place.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 300 AM Wednesday...Forecast for the short term, especially
for Friday, depends upon the exact track and strength of Hurricane
Matthew. Northeast flow will continue through much of the period
with high pressure anchored to the north and Hurricane Matthew
steadily advancing from the south. Winds become more easterly on
Friday, with tropical storm conditions possible Friday night.
Expect an enhanced rip current risk at the beaches through the
short term. Deep layer moisture advecting in with the approach of
Matthew will have pops increasing through the period, with heavy
rain possible Friday and friday night. See latest tropical
products for updated details on the track of Matthew and its
impacts.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 400 AM Wednesday...The primary focus over the next several
days and into the beginning of the long term forecast period will
remain on Hurricane Matthew as the latest track from the National
Hurricane Center, as of 2 AM Wednesday, projects the center to
pass just offshore of northeast SC/southeast NC Saturday evening
after it`s progressed northward up the east coast. Latest 00Z
guidance is illustrating a possible shift in track as the upper-
level synoptic pattern shifts. However, given the location of the
storm at this time, anticipate the projected path and intensity of
Matthew to remain uncertain for a few more days. With that said,
significant impacts remain likely at this time, with rough surf
and dangerous rip currents, gusty winds, downed trees, and
potentially excessive rainfall. Some areas may observe up to 10
inches of rainfall, but again, a clearer picture of the weekend
forecast will evolve as the Matthew nears the forecast area.
Into next week, expect conditions to become fairly quiet as high
pressure builds into the region. A drier and cooler airmass will
bring early fall-like temperatures to the area Monday and Tuesday,
with high`s in the lower 70`s and overnight lows in the mid 50`s. A
slight warming trend to climo temperatures occurs on Wednesday, with
high`s in the mid 70`s.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
As of 12Z...High pressure centered north of the region will control
the weather through the forecast period. A very weak coastal trough
will try to bring showers to the coast, however the majority of the
precipitation will remain offshore, as depicted by the HRRR model. A
fairly tight northeast gradient will be featured today, with some
gusts to 25 kts possible especially this afternoon. A predominately
MVFR ceiling will prevail for most of the forecast period, possibly
scattering briefly this afternoon.
EXTENDED OUTLOOK...VFR inland terminals, MVFR coastal
terminals on Thursday. Reduced flight restrictions due to low
clouds/rain/breezy and gusty winds are possible Friday through
Saturday as Hurricane Matthew tracks along or near the Southeast
U.S. coast.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
As of 1202 PM Wednesday...Latest observations continue to show NE
winds at 20 to 30 kts and 6 to 8 foot seas, thus Small Craft
Advisories continue.
A tight gradient between high pressure to the north and Hurricane
Matthew advancing from the south will keep a strongly-worded
Small Craft Advisory in effect through the near term and beyond.
Expect NE winds of 20 to 25 kts with gusts up to 30 kts and seas
of 6 to 8 ft today and tonight. Wave periods dominant between 8-9
seconds. Patches of light rain and isolated showers will track to
the SW over the 0-20 NM waters today and tonight.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 300 AM Wednesday...Expect small craft advisory criteria, or
worse, to be easily met through the short term as marine
conditions continue to deteriorate in advance of Hurricane
Matthew. Tropical Storm conditions will be possible on Friday,
with Hurricane conditions possible on Friday night.
LONG TERM /SATURDAY THROUGH SUNDAY/...
As of 400 AM Wednesday...Anticipate hazardous headlines on
Saturday and Sunday per the latest forecast from the National
Hurricane Center, as of 2 AM, which continues to project the
center of Hurricane Matthew just offshore of northeast
SC/southeast NC Saturday evening. However, dangerous and rough
water conditions will already be in place Saturday morning with
seas around 10 to 15 ft,and near 15 to 30 ft in the outer waters.
At this point, sustained east-northeast winds will be near
tropical storm force with higher gusts. However, it should be
noted that the intensity and strength of Hurricane Matthew remains
uncertain, and will become clearer as the storm nears the east
coast in the next few days.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...Beach Hazards Statement until 8 PM EDT this evening for SCZ054-
056.
NC...Beach Hazards Statement until 8 PM EDT this evening for NCZ106-
108.
MARINE...Small Craft Advisory until 6 AM EDT Friday for AMZ250-252-254-
256.
&&
$$
SYNOPSIS...ILM
NEAR TERM...MJC
SHORT TERM...REK
LONG TERM...SGL
AVIATION...DL
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
636 AM CDT Wed Oct 5 2016
.SHORT TERM...
252 AM CDT
Through Thursday night...
Increasing chances for occasional showers or storms over the next
few days, and timing the highest coverage is the focus of the
short term forecast, along with the above normal temps.
Things are quiet initially this morning with some increasing
clouds and southeast flow. Upper low pressure over the far
northern plains is resulting in moist southwest flow across the
central plains and just to our west this morning. Regional radar
mosaic depicts a complex of showers and thunderstorms that on the
southern fringe have generally been weakening/shrinking in
coveargeas instability wanes and also being removed from the main
forcing to the north, but a stout LLJ continues to feed into and
ahead of the front across the plains. The LLJ will weaken veer
overnight shifting the moisture transport axis towards our area,
but it will be in a much weaker state. There could be a few
showers in the morning as a lead shortwave and weak moisture
transport slides through, but many guidance sources are mostly
dry. As the occluding front continues eastward, there could be
enough forcing for a few showers or storms, especially from
Chicago eastward, mainly in the afternoon. Have some pops in today
to lend some credence to the 4km NAM but the RAP and both HRRRs
are dry. Cloud cover early will initialy slow the warmup but highs
back well into the 70s to near 80 are a good bet today.
Things get a bit more muddled tonight as the upper level jet strengthens
to our northwest, the moist LLJ (right from the Gulf) ramps up to
our southwest, south of a now slightly stalled out warm frontal
boundary across the central plains and extending into
Missouri/southern IA. A warm and moist airmass will exist behind
this front. The bulk of guidance really keeps forcing overnight
focus west of the area closer to the upper forcing, and southwest
closer to the warm front. The front is forecast to lift northward
to some degree late tonight into Thursday morning ahead of upper
forcing to the west and a ramp up of the low level jet. While some
precip is possible overnight, and even suggested by the NAM and
several other Hi-res models, the better chance at this time
appears to be late tonight into the morning as the front lifts
with the LLJ, and have carried chance pops for many areas, highest
W-S, though confidence on this time frame is not overly high on
what coverage will look like.
A secondary shortwave along the base of the upper trough will swing
northeast into Iowa Thursday afternoon, and additional organized
convection will initiate. Cyclogenesis continues as the low
strengthens as it shifts into WI and toward Lake Superior tonight.
Some showers are possible through the day as the front lifts
through the area, with the axis of stronger activity getting close
to the area in the evening. Enough forcing slides in later this
evening and overnight to support this activity getting into NW and
portions of NC Illinois, though a weakening trend is noted in
model QPF fields.
KMD
&&
.LONG TERM...
252 AM CDT
Friday through Tuesday...
Remarkably, model agreement on the Friday through the weekend period
has improved dramatically from 24 hours ago at this point. Both
the Canadian and GEM have shifted into the ECMWF camp. The theme
of the forecast has not changed with our transition back to cooler
weather for the weekend, but the degree of cold appears to be
tempered a bit. If this guidance shift towards the EC is correct,
the cold front will arrive at our western CWA by daybreak Friday,
if not sooner per the EC., then cruise southeast through the area
on Friday. There may be some decaying showers from the convective
complex to our west overnight into Friday morning, but then it
things turn cooler and initially breezy for the rest of Friday
with significant drying occurring behind the front.
Deep high pressure extending from the Canadian prairies and into
central plains will build over the Great Lakes region Saturday, then
shift to the eastern Great Lakes Sunday. and the weekend will be
dry, making for an initially cool but dry weekend. The high will
move east Sunday, and breezy southwest winds will make for another
mild and mostly sunny/partly cloudy afternoon. Broad southwest
flow into early next week will keep conditions mild with some
smaller chance for precip.
For those with interests on the east coast, the implications of
the upper level energy with this front cruising quickly to the
east this weekend is a vastly different track to Hurricane Matthew
after its initial impacts on Florida and the Carolinas during the
weekend, with guidance no longer bringing the tropical system up
the east coast early next week. Spread with this system beyond the
near term is very large. For more information, read WPC`s PMDEPD
long range model discussion and the NHC 5 day forecast.
KMD
&&
.AVIATION...
For the 12Z TAFs...
There are no significant weather concerns during the day today.
However, gusty south-southwesterly winds are expected during the
day, along with a small threat of a shower this afternoon.
No major changes were made with the 12z TAFs. It still appears
the morning should remain precip free at the Chicago area
terminals, though south-southwesterly winds will likely become
gusty up around 20 KT by mid morning. This afternoon an upper
level disturbance is expected to shift northeastward from IA into
WI, and this will likely help focus some showers and possibly a
few storms today. However, given the northeastward trajectory of
this disturbance, it appears the best focus for these showers and
storms today will largely be north of the area in WI.
A second weather disturbance is expected to shift over the Central
Rockies tonight. As this occurs, it appears that a stronger
northward flux of moisture may set the stage for overnight
showers and thunderstorms, especially over portions of northern
MO, southern IA and adjacent sections of western IL. Confidence
is low on how far east towards the Chicago area terminals these
storms may get by daybreak Thursday, but we cant rule out the
possibility at this point. Given the low potential, I have opted
to only include a PROB30 mention for TSRA at ORD for Thursday
morning.
KJB
&&
.MARINE...
231 AM CDT
Strong pressure falls, associated with low pressure over southern
Manitoba, have been overspreading the Upper-Midwest overnight and
resulting in some stout southeasterly winds over the open waters
of Lake Michigan. In fact, many marine observing sites, including
the open water buoys have been reporting gusts of 25 to 30 KT over
the past couple hours. These winds will continue today, but will
gradually become southerly this afternoon. Winds will then begin
to weaken this evening as the surface gradient abates over the
lake. Expect these lighter southerly winds to continue into
Thursday. Strong southerly winds (up around 30 KT) are expected to
make a return though by Thursday night into early Friday as
another storm system rapidly shifts northeastward from the Central
Plains towards the Western Lakes Region. The low will then drive a
cold front eastward over the lake Friday, with a period of gusty
west-northwesterly winds likely in its wake. These northwesterly
winds should gradually ease this weekend as a surface ridge of
high pressure builds in over the the Southern Lakes Region.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Memphis TN
1033 AM CDT Wed Oct 5 2016
.DISCUSSION...
A quick moving mid level shortwave is lifting through Southeast
Missouri and Northeast Arkansas this morning. Scattered showers
and a few thunderstorms have rolled through a good deal of East
Arkansas, the Missouri Bootheel and extreme West Tennessee over
the past few hours. This activity has started to taper off from
the southwest and will continue lifting northeast out of the area
over the next couple of hours. Expect increasing amounts of
sunshine across the area that have seen rain this morning as the
shortwave lifts out this afternoon. Temps will climb to 90F
across North Mississippi...a little cooler to the northwest where
it has rained.
SJM
&&
PREV DISCUSSION... /issued 225 AM CDT Wed Oct 5 2016/
DISCUSSION...
An upper ridge will continue to dominate the forecast over the
next seven days. Currently, skies are clear across the Mid-South.
Looking at latest radar and satellite images, a line of showers
and thunderstorms that developed earlier in the evening across
Kansas and Oklahoma has pushed east into Southwest Missouri and
Northwest Arkansas. The latest HRRR has the line dying out before
it reaches Northeast Arkansas. However, several other models
including the NAM and GFS have the line reaching Northeast
Arkansas later this morning. As a result, have left small POPS for
Northeast Arkansas and the Missouri Bootheel today. This may
actually be the best chance for rain that the area will have over
the next seven days.
After today, the only POPS that are in the forecast are for Friday
afternoon for Northeast Arkansas and the Missouri Bootheel ahead
of a cold front. However, the chances are rather slim as models
are showing whatever convection that develops ahead of the front
to quickly dissipate as the front pushes into the Mid-South due to
the dry air in place.
Thus, above normal temperatures and dry conditions will prevail
through Friday. Highs will range in the mid 80s to lower 90s.
Lows will drop off into the 50s at night thanks to the dry air in
place. Once the cold front pushes through the area Friday Night,
highs will drop back into the 70s. Although the upper ridge will
quickly begin to rebuild over the region by the latter part of the
weekend resulting in highs creeping back into the 80s for the
beginning of next week.
The biggest weather concern for the week may be with fire weather.
The drought remains ongoing across North Mississippi. With the
dry air in place, relative humidity values will drop below 30
percent almost everyday creating elevated fire danger over much of
the upcoming week. Saturday may be particularly dangerous as gusty
winds behind the cold front could potentially cause a rare red
flag event. Fire weather partners will need to stay tuned to the
latest fire weather forecasts.
KRM
&
AVIATION...
/12z TAFs/
An area of showers and thunderstorms continues to move east across
northern AR early this morning and is just entering the northwest
reaches of the CWA. This convection will slowly weaken throughout
the morning hours following the low-level dissipates. Showers
and/or a brief thunderstorm are most likely at KJBR, with
probabilities decreasing to the southeast. Ceilings will remain
VFR outside of this convection, with south winds of 7-10 kts.
Expect generally dry weather this afternoon with a Cu field around
6-7 kft. Winds will diminish this evening, backing from the
southeast.
Johnson
&&
MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&
$$
Area Forecast Discussion
National Weather Service Medford OR
852 AM PDT WED OCT 5 2016
.DISCUSSION...The forecast looks pretty good right now, so no
updates are needed at this moment. We will probably do an update
later this morning, depending on 12Z guidance and how
precipitation evolves through the morning.
A closed upper low is moving through western Washington right
now, and the associated trough axis is swinging across our area.
As expected, showers have been plentiful from the Cascade crest
westward, and some of them have been rather heavy. Some coast
range sites picked up three quarters of an inch in just 3 hours,
and a site over the Curry coastal range (Flynn Prairie RAWS)
recorded 0.38 inch in just one hour. The main band of showers will
move through Medford proper over the next couple of hours, and
while we don`t expect such heavy amounts here, it will be a wet
morning. The mountains above 6000 feet or so have been getting
snow. Based on cameras at the Crater Lake rim, it looks like
they`ve had an inch or two with more to come. No new snow is
evident on the Mt. Ashland cam, but they should get some as this
wave moves through.
Regarding thunderstorm potential: there is more elevated
instability indicated this morning than yesterday, but cool
surface conditions will limit surface-based instability to
virtually nil. While we can`t rule out a clap of thunder across
the northern half of the forecast area today, don`t think the
potential is much this morning. A little higher potential may be
this afternoon as greater dynamics move through and showers become
more scattered with some instability-inducing sun breaks in
between. We will watch this closely.
The question is: what happens behind this band? There isn`t nearly
as much convection offshore as yesterday, but models continue to
indicate considerable shower activity as the back side of the
trough moves through this afternoon. We`ll wait and see on that,
but if an update is to be made later, it would probably be to
lower pops behind this initial band. -Wright
&&
.AVIATION...05/12Z TAF CYCLE...Over Southwest Oregon, expect VFR
and areas of MVFR CIGS today and this evening, with MVFR cigs
and terrain obscuration most prevalent along the coast and into
the Southern Oregon Cascades where showers will be numerous to
widespread. An isolated thunderstorm cannot be ruled out today,
mainly north and west of the Umpqua Divide and along the coast.
Showers will be isolated to scattered east of the Cascades and
over Northern California with mainly VFR conditions and only local
MVFR cigs as well as areas of mountain obscurations. -CC
Note: The ceilometer at FAA site KOTH is out of service, so there
will be no ceiling observations available generally between the
hours of 04Z and 14Z.
&&
.MARINE...Updated 230 AM PDT Wednesday, October 4, 2016...
Northwest swell is building over the marine waters overnight into
the morning. Swell will become high and steep to very steep across
the waters this morning and persist into the afternoon as a storm
system drops southeastward through the northeast Pacific. Very
steep hazardous warning level seas of 14 to 16 ft at 12 seconds
are expected to impact most areas north of Cape Blanco beyond 10
nm from shore today. Elsewhere expect high and steep seas of 11 to
15 ft at 13 seconds. Seas will gradually subside below 10 feet by
early Thursday morning. A frontal system may graze the area
Thursday night into Friday, then high pressure will build in late
this week into this weekend. -CC
&&
.PREV DISCUSSION... /Issued 228 AM PDT WED OCT 5 2016/
DISCUSSION...A well-defined trough will move through the
forecast area today from the northwest and will bring a period of
enhanced shower activity. Morning infrared satellite imagery shows
the trough reaching the coast now, bringing rainfall to coastal
counties. Other areas are measuring rainfall this morning too, due
to continued deep onshore flow in a rather moist and unstable air
mass.
A few elements could come together today to bring thunderstorms and
gusty winds to portions of the West Side. Noting a healthy wind
profile with 0-6km bulk shear values 30kt+ and 25-30kt of southwest
to west winds from 700mb down to the surface, gusty winds could
certainly accompany any thunderstorms that form today. Additionally,
instability has trended higher compared to yesterday`s models for
areas west of the Cascades, and the HRRR has been consistent in
showing a group of thunderstorms progressing from the coast inland
this morning. Surface heating will be minimal this morning, so
confidence is low on significant thunderstorm activity, but we have
changed wording to coverage (isolated) to show increasing confidence
based on the latest data. Day shift will monitor 12Z model runs to
see if instability progresses east of the Cascades this afternoon,
and thunderstorms could be added to the forecast there if needed.
Elsewhere, a solid inch+ of rainfall is expected near the Curry
County coast. Also, up to 5 inches of wet snow is possible at the
Crater Lake rim, where snow levels are expected to be around 6000
feet and favorable deep layer westerly winds will optimize
orographic lift today. Travel impacts are expected to be minimal
based on the high snow levels, but morning road surface
temperatures in the mountains are in the 30s, and be prepared for
perhaps some morning slushy conditions on the very highest
mountain roads.
Thursday should be dry and warmer over the forecast area under low
amplitude ridging. Thursday night into Friday morning a weak
disturbance will scrape the coast and Umpqua Basin with a slight
chance for light rain then push northward, leaving Friday afternoon
into Sunday dry and warm, with temperatures nudging above normal by
a few degrees this weekend. Models have been waffling some with the
Thursday night system so confidence is low on actual rain amounts
and chances of precipitation, but impacts will be relatively low
with this rather weak system. We have introduced some patchy fog in
the Umpqua Valley Saturday morning to account for upper ridging,
expected clear skies aloft, and climatology that indicates the
season for fog in Roseburg in approaching, especially after recent
rainfall.
A more active weather pattern is expected by the middle of next
week. Atmospheric River confidence tools are showing increasing
potential for some moderate to strong AR events during week 2,
and the CFSv2 model suggests the same.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...None.
CA...None.
Pacific Coastal Waters...Small Craft Advisory for hazardous seas
until 5 AM PDT Thursday for PZZ350-356-370-376.
Hazardous Seas Warning until 5 PM PDT this afternoon for PZZ370.
$$
Area Forecast Discussion
National Weather Service Marquette MI
719 AM EDT Wed Oct 5 2016
.SHORT TERM...(Today and tonight)
Issued at 455 AM EDT WED OCT 5 2016
Water vapor imagery and RAP analysis show a broad trof covering much
of the w half of the CONUS with vigorous shortwave/mid level low
centered over the MT/ND/Saskatchewan border. Shortwave trof
extending from this feature and pivoting ne thru the plains is
supporting a relatively narrow band of shra/embedded thunder from MN
s thru Missouri. Over Upper MI, it`s been an unseasonably warm night
under a moist airmass and southerly winds. Current temps are near
normal max temps for this time of year...around 20 degrees above
normal.
Models remain in good agreement on fcst details today/tonight.
Shortwave trof currently pivoting ne across the Plains will lift
across the Upper Great Lakes today, propelling sfc cold front across
the fcst area. Given abundant column moisture with precipitable
water around 1.3 inches/more than 200pct of normal and decent deep
layer forcing, expect the relatively narrow band of shra/embedded
thunder currently moving into the Upper Mississippi Valley to hold
together and sweep across the area today, giving most locations
roughly a 2-3hr period of steadier pcpn. There may be some narrowing
of the pcpn area and a breakdown of a solid band of shra toward a
band of sct/nmrs shra with time as convergence along cold front and
deep layer forcing begin to weaken. Avbl instability supports some
embedded thunder, and not out of the question that tstm coverage may
increase a bit with front moving across the central and eastern fcst
area during the more favorable time of the diurnal cycle. Rather
sharp deep layer q-vector divergence/drying behind cold front will
bring a quick end to pcpn along with clearing skies from w to e late
aftn and evening. However, with limited CAA allowing nocturnal
inversion development, drying of the lowest levels may not be
sufficient to avoid development or persistence of low clouds over
the eastern fcst area tonight. Fog could develop as well.
As for temps, despite clouds/shra, another unseasonably warm day is
expected given the unseasonably warm start to the day. Expect high
temps in the mid 60s to lower 70s. Drier air mass, clear to partly
cloudy skies and diminishing winds will allow temps to fall back to
the mid 40s to lwr 50s tonight...still about 10 degrees above normal
for early Oct.
.LONG TERM...(Thursday through Tuesday)
Issued at 328 AM EDT WED OCT 5 2016
Thu wl be another warm day before an aprchg disturbance/lo pres
bring some wdsprd showers on Thu ngt into Fri. Cooler and drier air
wl follow the passage of this disturbance/lo pres into Ontario. An
aprchg disturbance/some deeper mstr over a lk induced trof that
dvlps over the relatively warm lk waters may result in some lk
effect showers on Sat before an aprchg hi pres brings a drying
trend. A fast zonal flow dominating late in the weekend/the first
half of next week wl support a changeable wx pattern along with
above normal temps.
Thu...While Thu wl at least start on the quiet side under lingering
mid lvl dry air in the wake of the Wed pcpn event, some of the
guidance, particularly the 12Z ECMWF, generate some pcpn during the
aftn over mainly the se cwa as a weak shrtwv rides newd parallel to
the stalled fnt and within the sw flow alf btwn persistent upr rdg
over the se ConUS and upr trof axis over the Rockies. Since this
scenario is not unreasonable considering the rather hi amplitude upr
pattern in place, wl retain some chc pops in the aftn over the se
cwa. Although the nw cwa wl remain dry, expect some incrsg clds even
there ahead of a stronger shrtwv lifting newd into central Plains.
Even if there are more clds over the se that would limit the diurnal
temp rise there, fcst h85 temps within a few degrees of 10C indicate
another unseasonably warm day is in store. If and where there is
more sunshine, temps could rise aoa 70.
Thu ngt/Fri...While the models are in fairly good agreement showing
the Plains shrtwv wl ride newd within the sw flow alf thru the Upr
Lks on Thu ngt and into Ontario on Fri, the guidance varies on the
intensity and thus the track of the accompanying sfc lo pres. Recent
ECWMF runs have shown a deeper sfc lo pres tracking farther to the
w, with most of the cwa falling into the warm sector. The models
that show a weaker sfc lo pres like the 00Z GFS indicate all but the
ern cwa wl be on the cooler wrn side of the fnt/weaker lo pres
track. Despite these differences, a period of vigorous dpva/deep lyr
qvector cnvgc/ upr dvgc with pwat as hi as 1.50 inch over at least
the se cwa wl support hi likely/categorical pops and a period of mdt-
heavy rain/ perhaps a TS. The guidance has come into better
agreement showing more vigorous drying/mid lvl subsidence by Fri
aftn under the jet surge region in the wake of the shrtwv/sfc lo
pres lifting into Ontario and attendant cold fropa. As h85 temps
fall toward about -2C by late in the day over the w, Fri wl turn
much cooler than on Thu.
Fri ngt/Sat...Although there wl be some drying in the initially acyc
wnw flow in the wake of the departing lo pres on Fri ngt, an aprchg
shrtwv/some deeper mstr/h85 thermal trof within a few degrees of -3C
over the relatively warm waters of Lk Sup are fcst to initiate some
lk induced troffing and at least sct showers over mainly nrn Upr MI
late Fri ngt thru much of Sat. A shrtwv rdg/larger scale subsidence
following the shrtwv wl bring a drying trend by late Sat. Temps over
the interior scentral could turn rather chilly on Fri ngt, but a
steady wnw flow with h925 winds up to 25 kts should limit the
diurnal temp fall a bit.
Later weekend...Although the models differ on timing within a fairly
tight wnw flow alf Sat ngt/Sun, sfc hi pres trailing the departing
shrtwv is fcst to slide acrs the Upr Lks sometime during this
period. If the hi pres/mid lvl dry air are ovhd Sat ngt, the overngt
could be rather chilly. But the faster 00Z GFS shows some waa clds
overspreading the area on Sat ngt as the hi pres exits to the e and
a quick moving shrtwv riding along the Cndn border aprchs.
Considering the fast wnw flow dvlpg near the Cndn border, suspect
the quicker GFS might be on the right track.
Early next week...Not surprisingly with a zonal flow, model
differences remain quite pronounced next week with quick moving
disturbances embedded in this fast flow. In general, since hgts wl
be well above normal, expect above normal temps to prevail even
though a cool fnt in the wake of one of these passing disturbances
could drift thru the Upr Lks at some point during this time
accompanied by some sct showers.
&&
.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 719 AM EDT WED OCT 5 2016
LLWS will end this morning as core of stronger low-level winds ahead
of an approaching cold front shifts e. Otherwise, cold front will
sweep across Upper MI this aftn/evening, bringing a period of shra
and a short period of MVFR conditions to KIWD/KCMX/KSAW. While tsra
are possible, confidence in occurrence at any of the terminals is
too low to include mention in fcst. After fropa, expect rapid
improvement to VFR conditions with clouds clearing out.
&&
.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 455 AM EDT WED OCT 5 2016
Ahead of a cold front sweeping across Lake Superior today thru early
this evening, SE to S winds up to 20-30kt are expected, strongest
over the central and east part of the lake. While SW winds as high
as 20-30kt should occur behind the front tonight into Thu morning,
strongest between Isle Royale and the Keweenaw Peninsula, the
pressure gradient and winds will weaken for a time Thu aftn and
night as a low pressure trough develops over the Upper Lakes ahead
of a low pressure wave developing over the southern Plains. After
this low pressure wave passes late Thu night/early Fri morning, NW
winds up to 30kt will develop on Fri, strongest over the e half of
Lake Superior. NW winds up to 20kt will linger into Sat before
diminishing to under 15kt late Sat into Sun as high pres arrives.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...Rolfson
LONG TERM...KC
AVIATION...Rolfson
MARINE...Rolfson
Area Forecast Discussion
National Weather Service Paducah KY
647 AM CDT WED OCT 5 2016
.UPDATE...
Issued at 647 AM CDT Wed Oct 5 2016
The scattered showers are moving into the westernmost 4 counties
in southeast Missouri right on schedule.
The AVIATION section has been updated for the 12Z TAF issuance.
&&
.SHORT TERM...(Today through Friday night)
Issued at 331 AM CDT Wed Oct 5 2016
All eyes are to the west where a band of convection is attempting
to push eastward through central and southwest Missouri. With the
stronger thunderstorms propagating southeast toward Arkansas, we
may not see much thunder with this activity as it moves into our
far western counties around or just prior to sunrise.
The latest HRRR and WRF runs continue to show scattered convection
moving into the area, but gradually diminish it as it moves
eastward through southeast Missouri and southern Illinois through
midday. They show very little convection left through the
afternoon and do not bring it into Kentucky or Indiana. Will
continue with chancy PoPs on the western border tapering to no PoP
in Kentucky and Indiana, mainly this morning, with only slight
chances in the afternoon.
The 00Z model consensus builds the upper ridge back over the
region, and allows the surface ridge to poke back into the area
for tonight into early Friday. The models try to push the main
upper trough through the region along with a cold front Friday and
Friday night, but with the ridging over the East Coast and
Southeast, the cold front basically dissipates, resulting in a
surge of surface high pressure through the area Friday afternoon
and night. Any convection associated with the approaching cold
front is expected to dissipate before reaching the area Friday.
As for temperatures, it will continue to be hot through the
period. High temperatures will be around 10 degrees above normal
today and Thursday, and may not be far from it on Friday depending
on cloud cover and timing of the high pressure surge. Thursday
will be the hottest day with upper 80s to 90 not out of the
question. Lows will be quite mild around 10-15 degrees above
normal tonight and Thursday night. Lows will trend down near
normal levels Friday night with the fresh surface high pressure
building over the region.
.LONG TERM...(Saturday through Tuesday)
Issued at 331 AM CDT Wed Oct 5 2016
Above average confidence in much of the extended period due to
operational deterministic and probabilistic model agreement in the
general synoptic pattern for our region.
The past few runs of the operational models have been continually
drier for the cold frontal passage into Saturday. As a much drier
and cooler air mass enters the mid Mississippi valley behind the
front, our typical moisture flow from the Gulf is blocked by upper
level ridging west of Hurricane Matthew. Thus, a dry and
pleasant forecast through Tuesday for this update.
The main uncertainty in the extended forecast develops starting
Tuesday when a series of upper level shortwave disturbances begin to
disrupt the Midwest. The latest 00z runs of the GFS/Euro/GEFS mean
show Matthew stalling east of Florida, which essentially prevents
most significant Gulf moisture from returning to our area and
results in rain chances remaining to our north and west. However,
most of the previous model guidance showed Hurricane Matthew
meandering out to sea, allowing for some rain chances mid week. Will
be interesting to monitor this progression over the next week.
For Friday night into Saturday, we will see a big drop from
temperatures above normal, down to slightly below seasonal normal
temps for the weekend. Highs on Saturday will reach the lower 60s to
near 70, and the overnight low early Sunday will bottom out in the
mid 40s. For early next week, daytime highs warm into the mid to
upper 70s, with lows in the low to mid 50s.
&&
.AVIATION...
Issued at 647 AM CDT Wed Oct 5 2016
The TAFs are VFR. Some scattered showers will drift northeast near
KCGI later this morning, but coverage does not warrant anything
more than a VCSH at this point. TS cannot be completely ruled out,
but is not likely to impact the terminal. The convection is
expected to die out before reaching KPAH or KEVV and should not
pose any threat to KOWB. These 3 sites will be dry throughout.
A lower VFR ceiling will be possible, but nothing as low as MVFR
today. All sites will see a decent south breeze by late morning,
and some gusts into the teens will be possible, especially at KEVV
and KOWB. All sites should be mostly clear with light, if not
calm, winds tonight. Cannot rule out fog, but the signal is not
strong enough to mention any visibility restrictions at this time.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
UPDATE...DRS
SHORT TERM...DRS
LONG TERM...BP2
AVIATION...DRS
Area Forecast Discussion
National Weather Service Caribou ME
306 PM EDT Wed Oct 5 2016
.SYNOPSIS...
High pressure will remain in control across the region through
first half of the weekend.
&&
.NEAR TERM /THROUGH THURSDAY NIGHT/...
Challenge again will be temps and frost/fog potential.
After a pleasant afternoon with above normal temps, clear skies
and light winds will allow for good radiational cooling once again
overnight. NAM and the HRRR soundings point to a llvl inversion
setting up w/moisture getting trapped in the blyr. The NAM
appeared to be matching up quite well per the last six hrs of the
12Z run with its temps/dewpoints. Therefore, w/temp and dewpoint
spread apchg 3 degrees, decided to keep fog in the forecast as the
midnight crew had advertised early this morning. This will mainly
be the case for the river areas and low lying locations. Expecting
temps to fall off well after sunset and especially by early
morning hrs on Thursday just before sunrise. After coordination
w/GYX, decided to go w/patchy frost for the low lying areas but
not as widespread as the last few mornings. The tricky part will
be how quickly the dewpoints can drop back before sun up.
Thursday will be another pleasant day and warmer w/most areas
apchg 70F or slightly warmer. The exception to this could be right
along the coast as a sea-breeze/on-shore wind sets up in the
early afternoon to be afternoon readings down a bit. High pres
staying anchored over New England will keep clear skies and light
winds Thursday night. Not nearly as cold as llvls are expected to
remain mild. Fog development is possible but coverage will be patchy
and will reference as such in the forecast.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
Quiet weather will persist through Friday night with high
pressure keeping its hold on the Northeast. The ridge axis will
begin to shift off to our east late Friday and Friday night,
placing us in southwest flow. This coupled with plenty of sunshine
on Friday will bring temperatures in the lower to mid 70s in most
places away from the coast; as is usual the coast will be a few
degrees cooler. Expect we`ll see patchy fog once again late Friday
night, especially central and Downeast where winds will be near
calm. Lows will be in the mid and upper 40s, some spots around 50.
The dry weather may finally come to an end as we head into the
weekend. The high will continue to push to the east as a cold front
approaches from the west. The front will cross the Pine Tree State
Saturday afternoon into the evening. Some of the model guidance is
fairly robust with showers and QPF for this frontal passage, while
others are more pessimistic - that is, drier. Given how dry we`ve
been over the past several days, have kept pops capped at 30% or so
as the front very well may come through dry. Temperatures will be a
little cooler than on Friday, mainly in the mid and upper 60s.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
As mentioned above, the cold front will move across the area late
Saturday into Saturday night, keeping the chance for showers
around into the overnight. Cooler and drier air will work in
behind this front, ending the threat for precipitation by Sunday
afternoon. As a result, Sunday and Monday will be dry but quite a
bit cooler than what we`re seeing this week. Overnight
temperatures will be in the lower 30s north and mid to upper 30s
Central/Downeast areas. A weak upper shortwave may bring some
showers to the north on Tuesday, with a weak frontal passage to
follow Tuesday night into Wednesday. This latter feature may also
produce a few showers as is passes through. Temperatures will warm
a bit heading into mid week, but will still be right around
normal.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
NEAR TERM: VFR through the period at all sites. As stated by the
midnight crew, early morning fog especially for northern sites and
possibly KBGR will reduce visibilities and cigs for a time to
MVFR/IFR into 8 AM. Another round of fog possible by early Friday
morning, but more shallow in nature and not as the last few
mornings,.
SHORT TERM: VFR conditions will prevail Friday and Friday night,
with a brief period of IFR/LIFR possible in patchy fog late Friday
night into Saturday morning. A cold front will cross the region
Saturday afternoon and may spark some showers, which could lower
ceilings and visibility to MVFR. High pressure resumes thereafter
along with VFR, outside of the patchy morning fog each day.
&&
.MARINE...
NEAR TERM: Light Winds 10 kt or less w/seas at best around 2 ft
w/high pres in control.
SHORT TERM: High pressure will build across the waters through the end
of the week, keeping both winds and seas below small craft levels.
Therefore, no headlines are anticipated.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...None.
&&
$$
Near Term...Hewitt
Short Term...Hastings
Long Term...Hastings
Aviation...Hewitt/Hastings
Marine...Hewitt/Hastings
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
551 PM EDT Wed Oct 5 2016
.SYNOPSIS...
High pressure will persist over the region into Thursday. Hurricane
Matthew is then expected to move northward and very near the Georgia
and South Carolina coasts Friday night and Saturday. A cold front is
then forecast to sweep across the western Carolinas Saturday night
and Sunday, with cool and dry high pressure settling over the region
in its wake.
&&
.NEAR TERM /THROUGH THURSDAY/...
As of 500 PM EDT...No sigfnt changes were made to the fcst grids.
Low strato-cu deck off to the east is slowly mixing in drier air
along the wrn periphery...so updated sky grids to capture this
trend. Hourly temp and td curves look good.
As of 220 PM: High pressure will remain centered over New England
through Thursday, providing northeasterly low-level flow and
reflecting strong midlevel subsidence. Beneath the resulting
inversion, fairly moist conditions will keep skies cloudy over much
of the mid-Atlantic region, including parts of our Piedmont. The
I-77 corridor has seen mostly cloudy skies throughout the day so
far, and while the latest guidance expects these will dissipate/lift
slowly thru the afternoon, lower ceilings will advect in overnight,
also expanding a bit further west. A few of the hi-res models
develop some light showers within the cloud deck along/east of
the Blue Ridge, but the upslope/upglide seems too weak to support
a mentionable PoP. Temps in the mountains will bottom out around
normal, but a few degrees above normal over the Piedmont where
clouds and slightly breezy conditions will persist.
Going into Thursday the pattern is more or less the same, with
the easterly flow still supportive of cloud cover but not PoPs,
at least thru the morning. The expectation is that the morning
stratus will dissolve, giving way diurnal cu/stratocu behind. As
Hurricane Matthew approaches the Carolinas over the course of
the day, however, the low-level gradient flow begins to pick up,
and upglide continues to strengthen. This brings clouds back from
east to west during the late afternoon, and a small chance of
rain to our southeastern zones prior to 00z Fri, which increases
after the end of the period. Thicknesses will be slightly higher,
and the airmass should modify further, so max temps will be a
category or so warmer than today.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
As of 245 PM Wednesday, a tough fcst for the late part of the week,
what with conflicting model guidance and operational models
struggling with run-to-run consistency. Fortunately, in the grand
scheme of things, it remains unlikely (if not highly unlikely) that
the western Carolinas and northeast GA will see significant rainfall
or wind based on the latest NHC track and the preponderance of the
model ensemble guidance. So, the scenario changes only slightly.
Still think that a strengthening/moistening easterly flow will bring
light precip in from the east across the Piedmont Friday evening,
with some of the moisture banking up against the Blue Ridge
resulting in additional development in the easterly upslope areas.
Moisture gradually deepens from there so precip chances only
gradually expand overnight and through Friday morning. It will
probably take until an outflow jet from Matthew is brought to bear
late Friday before steadier precip, and thus higher precip chances,
develops this far N and W. Will ramp up precip chances into the
likely range over the eastern third of the fcst area Friday night.
Would not be surprised to need a trend toward categorical over at
least the SE half of metro Charlotte by Saturday morning, at which
time the official track of Matthew has its closest position. Beyond
that time, uncertainty really goes up, especially in light of the
brand new operational ECMWF. Will take precip chances back down
across the fcst area thru Saturday as the official track moves the
storm off to the east, but this period is the most likely to change
in later issuances. Again, at this point, none of the guidance shows
enough precip to pose a significant flood threat across the GSP
area. Although we would have a breezy period Friday thru Saturday,
wind speed/gusts do not look strong enough to pose a significant
damage risk. Once again, this is all subject to change with later
track fcsts. Temps will be highly dependent on where precip
develops, but generally would be warmest over northeast GA where
precip chances are lowest. Min temps should be mild.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 230 PM EDT Wednesday: Overall the extended is pretty quiet,
with the only "excitement" being at the very beginning as whatever
(and perhaps more importantly, wherever) Matthew is at that time
will still be peripherally impacting us (with his western fringe).
The new 12z ECMWF certainly befuddles the whole issue as it takes
Matthew back up to the NC coast and then east to the Atlantic, while
the 12z GFS never makes it past Charleston. The result for us would
be windier and rainier conditions lingering Saturday night with the
ECMWF. For now, with the ridiculously high levels of uncertainty,
went with a generic blend (while collaborating with neighbors) with
some low-end pops SE of Charlotte. It will still be kind of breezy
on Sunday on the subsident side of the tropical cyclone with weak
ridging building over the area, so temperatures should rise to
slightly above climatological normals.
For the rest of the period - that is, assuming Matthew doesn`t do
anything even crazier - zonal flow to weak ridging aloft will
dominate the area through midweek when a shortwave trough approaches
the area. Temperatures will be near seasonal normals for highs with
lows a category or so lower that normal. No mentionable pops through
the end of the period.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
CLT Update 22Z...Made an AMD to keep MVFR cigs in through the period.
Stcu deck is holding strong with moist ene/ly flow atop the llvl
wedge axis.
At KCLT and elsewhere: Dry high pressure will ridge down the
Eastern Seaboard thru Thursday. Primary impacts this period will
be low VFR to MVFR cigs which will remain over (or return to)
much of the CWFA. As moist easterly low level flow occurs around
the ridge, this moisture being trapped under midlevel subsidence
inversion. The 16z LAMP appears to handle the pattern well based
on an analysis of NAM and GFS low level fields, so this was the
primary cig guidance used. Over KCLT and the I-77 corridor however,
the LAMP seemed to dissolve cloud cover too quickly this aftn,
so the HRRR was blended in. With dry soils and a lack of surface
moisture advection, no vsby restrictions are included at any of
the TAF sites, though radiation fog is expected to develop in the
Little Tennessee river valley. Winds will be mainly NE, but pretty
VRB at KAVL. Low-end gusts are possible throughout the period,
but particularly during the daytime.
Outlook: A NE to SW surface ridge will persist across the western
Carolinas through Friday. This pattern will likely support a steady
NE wind through the rest of the work week. Hurricane Matthew could
result in breezy conditions with outer rain bands possibly reaching
the western Carolinas late Friday into Saturday.
Confidence Table...
22-04Z 04-10Z 10-16Z 16-18Z
KCLT High 80% High 97% Med 75% Med 76%
KGSP High 100% High 100% High 95% High 100%
KAVL High 100% High 100% High 82% High 100%
KHKY High 100% High 100% Med 71% Med 77%
KGMU High 100% High 100% High 97% 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...JPT
NEAR TERM...Wimberley/SBK
SHORT TERM...PM
LONG TERM...TDP
AVIATION...Wimberley/SBK
Area Forecast Discussion
National Weather Service Wilmington NC
525 PM EDT Wed Oct 5 2016
.SYNOPSIS...
Strong high pressure will build in from the north through the mid
week period. The center of the high will slide well offshore from
the Northeast states, allowing Hurricane Matthew to move
northwest through the Bahamas overnight and Thursday and near the
Florida coast Friday. Matthew will move up the the Southeast U.S.
Coast Friday and continuing thru the weekend but much uncertainty
remains during this time period. Cool high pressure will build
across the area from the west early next week in the wake of
Matthew.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
As of 510 PM Wednesday...Forecasts have been issued incorporating
the latest NHC Matthew forecast track.
Previous......................................................
As of 3 PM Wednesday...Cloudy and moderately breezy overnight as
the pressure gradient remains tightened between a high pressure
wedge to the north and west, and lower pressure southward. Gusts
of 20-30 mph will be common along NE SC and SE NC beaches through
tonight along with rugged surf, although no coastal flooding is
expected as the astronomical influence is not strongly phased at
present. An extensive blanket of clouds likely to remain draped
across the region as is signature of the classic wedge pattern.
Blusterous northeast winds will maintain elevated minimum
temperatures near the coast 68-72, and a cooler less tempestuous
63-67 degrees over the interior. Minimal rain chances and mainly
near the coast in periodic patchy light, and QPF-wise, trace to a
few hundreths overnight along the eastern 1/3 land zones to
offshore.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
As of 3 PM Wednesday...The main weather caption this period is
mounting chances for rain as Hurricane Matthew begins to ride up
along the east coast of FL. The other notable headline is a good
chance of a Hurricane Watch for NE SC into THU. Rain rates and QPF
values will remain minimal through Thursday, becoming substantial
late Thursday night onward as periods of rainfall move ashore. The
official hurricane track curls Matthew east and farther offshore of
the SC coast, but this remains susceptible to adjustment based on a
history of model inconsistencies so far. The official track implies
a 70 percent chance of at least tropical storm force winds along the
NE SC and very SE NC coast at this time by Saturday. 4-8 inch rain
amounts from late THU through SAT remains advertised for now, and 2-
4 inches farther inland of NE SC/SE NC.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 3 PM Wednesday...Uncertainty remains the key word to describe
the first and what is probably the most important portion of the
forecast period. Latest trend in the guidance has been to sharply
turn Matthew near the GA/SC border with significantly less impacts
in the local area than previously expected. However, the 12Z
ECMWF, which was the first with the sharp eastward turn idea
yesterday, has reverted back to a track up the coast albeit with a
weaker storm. The lack of consistency in the past 24 hours is
somewhat disconcerting and do not expect a lot of changes with the
next NHC advisory.
The fate of Matthew will also play a role in how next week plays
out. A track up the coast instead of kicking out to sea south of
the forecast area would linger clouds/wind/rain into Sun morning
before the storm exits and the surface/mid level ridge combo can
build in. Latest forecast maintains high pop Sat with a decreasing
trend Sat night and Sun with the remainder of the forecast dry as
west to northwest flow aloft and low level northeast flow contribute
to cool and dry conditions. Temps early next week below climo will
trend toward climo by the end of the period.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
As of 18Z...High pressure centered north of the region will control
the weather through the forecast period. A very weak coastal trough
will try to bring showers to the coast, however the majority of the
precipitation will remain offshore, as depicted by the HRRR model. A
fairly tight northeast gradient will be featured today, with some
gusts to 25 kts possible especially this afternoon. A predominately
MVFR ceiling will prevail for most of the forecast period, possibly
scattering briefly this afternoon. Tonight, will stick with MVFR at
all terminals. Thursday, increasing chances for precip along the
coast as deeper moisture moves onshore. Continued gusty northeast
winds.
EXTENDED OUTLOOK...VFR inland terminals, MVFR coastal
terminals on Thursday. Reduced flight restrictions due to low
clouds/rain/breezy and gusty winds are possible Friday through
Saturday near the vicinity of Hurricane Matthew.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
As of 510 PM Wednesday...Forecasts have been issued incorporating
the latest NHC Matthew forecast track.
Previous........................................................
As of 3 PM Wednesday...Advisory flags remains flapping, this for
5-8 foot seas and 20-30 KT NE winds through tonight. NO TSTMS over
the 0-20 NM waters through tonight but patchy light rain can be
expected along the coast and offshore. Wave periods between 7-8
seconds and an incoming wave direction of ENE. Mariners are
encouraged to secure and tie down small craft at this time as
conditions will worsen in the days ahead.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 3 PM Wednesday...Advisory conditions are certain this period
but could be superseded by a tropical storm or hurricane watch for
part of our waters into Thursday. In any case marine conditions will
become increasingly dangerous this period. By Saturday wave guidance
suggests 10-16 foot seas across the 0-20 NM coastal waters. This
could change to higher values if Matthew does not turn east as soon
as is currently forecast. Mariners are encouraged to secure and tie
down small craft at this time.
SHORT TERM /SATURDAY THROUGH MONDAY/...
As of 3 PM Wednesday...Although the magnitude of marine impacts will
depend on Matthew`s track it seems certain headlines will be in
effect Sat morning. Seas could be well into the double digit range
with winds of hurricane force if a track on the western edge of the
guidance envelope verifies. Should this happen treacherous marine
conditions would be more likely to linger through Sun and possibly
Sun night. Conditions should begin to improve at the latest on Mon
as high pressure at the surface and aloft starts building over the
region.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...Beach Hazards Statement through Thursday evening for SCZ054-
056.
NC...Beach Hazards Statement through Thursday evening for NCZ106-
108.
MARINE...Small Craft Advisory until 6 AM EDT Friday for AMZ250-252-254-
256.
&&
$$
SYNOPSIS...MJC
NEAR TERM...DCH/MJC
SHORT TERM...MJC
LONG TERM...III
AVIATION...JDW/DL
AREA FORECAST DISCUSSION
National Weather Service Northern Indiana
303 PM EDT Wed Oct 5 2016
.SYNOPSIS...
Issued at 300 PM EDT Wed Oct 5 2016
Outside an isolated shower threat north of highway 6 late this
afternoon dry and mild weather will continue through Thursday.
Lows near 60 tonight with highs Thursday afternoon in the low
80s.
&&
.SHORT TERM...(This Evening through Thursday)
Issued at 300 PM EDT Wed Oct 5 2016
Trailing prefrontal trough extending from sw disturbance over srn
Canada extends down across lake MI. Earlier shower activity back
through ern IL had diminished entirely as it became divorced from
better forcing aloft passing well northwest and better moisture
down near the OH river. Lastest RAP along with various 12Z highres
solutions depict minimal to no redevelopment invof of prefrontal
trough.
Focus overnight shifts well west across MO/ern IA along stalling
surface trough and see little reason not to buy into broad consensus
drier look of 12Z guidance given 1) absence of relevant focusing
mechanism 2) poor low level moisture flux underneath 3) mid level
capping inversion. Did retain slgt chance shower mention far west
late corresponding to eastward bulge of modest low level theta-e
ridging poking newd into central IL however this may very well
hold west too.
&&
.LONG TERM...(Thursday Night through Wednesday)
Issued at 300 PM EDT Wed Oct 5 2016
Large scale shift seen in gamut of model solutions overnight with
ejection/intensity of sw energy out of the Rockies on Fri with a
much weaker and faster solution aloft with lagging disturbance
lifting out of base of trough across the central plains.
Deamplifying trends with this sys and eastward weakening of sfc
frontal zone suggest little if any shower activity will persist
into the KIWX CWA on Fri and will follow previous shift trend of
limiting pops further.
Otherwise expansive ridging will return to the lakes/OH valley this
weekend into early next week. Seasonably cool temps this weekend
will give way to a moderating trend back to above normal next week
as general zonal flow develops across the Conus.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1253 PM EDT Wed Oct 5 2016
An upper level shortwave lifting ne through the northwest Great
Lakes will force a weakening pre-frontal trough east into
northern IN later this afternoon/tonight. Large scale forcing
appears weak locally, but could be just enough
moisture/instability and low level convergence to generate
scattered showers into KSBN mid-late afternoon and possibly KFWA
late afternoon/early evening. Covered with a VCSH mention for now
given uncertainties regarding coverage and very low thunder
chances.
Chances for rain should focus northwest of the terminals later
tonight into Thursday. Mixed signals for fog in guidance later
tonight/early tomorrow given partial clearing, light winds, and
ample boundary layer moisture in pre-frontal theta-e ridge. Opted
to make no changes at this forecast range as an result (MVFR BR
toward daybreak).
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...T
SHORT TERM...T
LONG TERM...T
AVIATION...Steinwedel
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Area Forecast Discussion
National Weather Service Saint Louis MO
332 PM CDT WED OCT 5 2016
.SHORT TERM... (Through Late Thursday Afternoon)
Issued at 332 PM CDT Wed Oct 5 2016
It is currently dry over the area with showers just south of
Reynolds county. This area could still bring isolated showers to
the far southern part of the CWA through late this afternoon. Of
more concern is that I still expect thunderstorms to redevelop this
evening across central and northeast Missouri as well as west
central Illinois this evening and overnight. Latest RAP runs
continue to show low level moisture convergence increasing over
these areas ahead of a mid level vort max currently over the central
Plains. Will continue to go with high chance and likely PoPs
tonight to account for this forcing. May still be a few strong or
possibly severe storms based of the amounts of shear and instability
available tonight.
As we go into tomorrow, the chances for showers and thunderstorms
will begin to lessen as the low level jet weakens. Will maintain a
chance for showers and thunderstorms through the day across central
and northeast Missouri and west central Illinois where will continue
to be some weak low level moisture convergence. Look like the rest
fo the area will continue to be dry.
Temperatures will be relatively mild tonight and tomorrow. Stayed
close to MOS guidances which is in good agreement.
Britt
.LONG TERM... (Thursday Night through Next Wednesday)
Issued at 332 PM CDT Wed Oct 5 2016
The cold front will be moving into northwest Missouri Friday
evening. All guidance is more progressive with the front now as the
shortwave trof aloft does not amplify the longwave trof as much as
previously forecast. This faster pattern now has the front all the
way through the CWFA by 18Z Friday. Showers and thunderstorms along
the front will likely be weakening and dissipating through the
morning with diurnal minimum in heating. Some weak showers or
sprinkles will continue to be possible mainly behind the front as
low level frontogenesis increases sharply over the area. Due to the
faster movement of the front, will keep more moderate temperatures
over the area on Friday than I forecast yesterday.
High pressure will build over the region Friday night and Saturday
behind the front. This will be another true taste of Fall with
highs in the upper 60s and low 70s and lows mainly in the 40s. As
the ridge moves eastward early next week, we should get into a
return flow pattern and temperatures will get a bump back above
normal...tho right now it looks like it will only get a few degrees
above into the mid 70s. Ensemble guidance is giving us some slight
chance PoPs over central Missouri late Tuesday night and both the
GFS and ECMWF do show some weak moisture convergecne and low level
warm advection so I see no harm in leaving the slights in for now.
Other than that it should be a dry medium range with the ridge axis
still across the lower Mississippi Valley limiting moisture
return.
Carney
&&
.AVIATION... (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1240 PM CDT Wed Oct 5 2016
Expect mainly dry and VFR conditions are expected at the
terminals through the afternoon hours. There will be a chance of
thunderstorms at KUIN this evening and overnight and have included
a PROB30 mention there. The chance of storms could continue into
morning hours at KUIN and KCOU, but do not have enough confidence
in the timing to include them in the terminals at this time. Any
storms could produce MVFR, possibly IFR ceilings and visibilities.
SPECIFICS FOR KSTL: Dry and VFR conditions are expected at this
time. Thunderstorms are expect to remain north and west of the
terminal for the next 30 hours.
Britt
&&
.PRELIMINARY POINT TEMPS/POPS...
Saint Louis 68 86 64 71 / 20 10 20 20
Quincy 64 82 59 64 / 70 50 60 20
Columbia 64 83 58 63 / 50 40 60 30
Jefferson City 65 85 60 66 / 40 30 50 30
Salem 63 84 62 78 / 10 5 5 20
Farmington 62 84 60 74 / 10 5 5 20
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...None.
IL...None.
&&
$$
WFO LSX
Area Forecast Discussion
National Weather Service Marquette MI
352 PM EDT Wed Oct 5 2016
.SHORT TERM...(This evening through Thursday)
Issued at 350 PM EDT WED OCT 5 2016
Upper level trough is over the northern plains to southern
Saskatchewan and Manitoba. Swath of showers and isolated tsra
in warm conveyor belt ahead of sfc cold front is sliding across
Upper Michigan this aftn. Dry slot and back edge of showers already
over western U.P. and should be out of eastern cwa early this
evening. Dry air evident upstream and expect skies to clear out
tonight. Lingering low-level moisture blo 1000ft may lead to patchy
fog over far east cwa after midnight. Though dry air aloft should
allow temps to fall off into the 40s over interior west tonight,
extent of dry advection should prohibit low clouds or fog. RAP
soundings for late tonight bearing this out attm. High clouds will be
on the increase late Thu morning into Thu afternoon.
Models have trended slower in bringing in next round of rain showers
and isolated thunderstorms into southern part of Upper Michigan
ahead of shortwave currently crossing northern CA and NV. Scaled
back on pops, limiting them to slight chance for scntrl and only
after 21z. Another day with above normal temps well into the 60s
if not near 70, especially with the sunshine in the morning.
.LONG TERM...(Thursday night through Wednesday)
Issued at 335 PM EDT WED OCT 5 2016
Thu night/Fri...Models in fairly good agreement on track of
shortwave and accompanying low pressure system riding ne from the
Plains into wrn Upper Mi Thu night although differ on timing. The
00Z ECMWF and 00Z GFS were a bit quicker than the 12Z NAM and the
local 12Z WRF-ARW while the 12z Canadian model was somewhere in
between. With the 12z GFS trending slower, more in line with the 12Z
Canadian, would tend to lean more toward slightly slower solution
with system. Despite the differences, models indicate a period of
vigorous dpva/deep layer q-vector convergence with pwats as high as
1.50 in over at least the central and ern cwa. This will support
high likely/categorical pops and a period of moderate to heavy rain/
perhaps a TS...especially for late Thu night into early Fri. The
guidance has come into better agreement showing more vigorous drying
/mid-level subsidence by late Fri morning west spreading east into
the afternoon in wake of the shortwave/sfc low pres lifting into
Ontario and attendant cold frontal passage. As h85 temps fall toward
-3C late in the day over the w, Fri will turn much cooler than Thu.
Fri night into Sat night...Although drying will initially persist in
the anticyclonic wnw flow in the wake of the departing low, an
approaching shortwave along with deeper moisture and h85 temps of -3
to -4c over the relatively warm waters of Lake Superior are fcst to
initiate some lake induced troughing and at least sct lake effect
showers over nw Upr MI late Fri ngt into Sat and over ne Upper Mi
Sat afternoon into Sat evening. The arrival of a shortwave
ridge/larger scale subsidence in the wake of Saturday`s shortwave
trough will bring a drying trend by late Sat night. Temps over the
interior west half could turn rather chilly on Fri ngt, but a steady
wnw flow and mixing from h925 winds 20-25 kts should limit the
diurnal temp fall a bit. Lighter winds and partial clearing with sfc
high moving overhead could lead to another chilly night on Sat
night, although the more progressive GFS indicates some waa clouds
overspreading the area late Sat ngt from west which may temper
cooling somewhat. Still wouldn`t be surprised to see some lower to
mid 30s min temps for both Fri and Sat nights over the interior west
half.
Sunday generally trending drier as models show another shortwave in
zonal flow passing well north into Canada keeping waa pcpn well
north of the area as well. Model uncertainty increases for Mon into
next Wed with differences in strength/timing of shortwaves moving
through south central Canada and also differences in timing with
cold front assoc with sfc low moving across Hudson Bay. Most of the
models with exception of 12z GFS would suggest drier conditions
persisting into Monday as higher 5h ridge heights hold over the
region. Model consensus would then indicate cold front advancing
into Upper Mi late Mon night into Tue so slight chc to low chc pops
will be probably be warranted during this time frame. In general,
since heights will be well above normal, expect above normal temps
to prevail for the first portion of the week even with the expected
passage of the cold front.
&&
.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 145 PM EDT WED OCT 5 2016
Approaching cold front will bring showers and isold tsra to all the
TAF sites this aftn. MVFR conditions expected mostly due to lower
cigs. Skies clear out from west to east late this aftn into this
evening as the front moves through. Expect clear skies later this
evening to continue through end of TAF period. Mid clouds will
increase again on Thu aftn ahead of a low pressure system that will
bring showers to area by Thu night. Only issue tonight will be low-
level wind shear at IWD with a 35-40 kt low-level jet atop a developing
sfc based inversion.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 350 PM EDT WED OCT 5 2016
S winds 20-30 kts shift to the SW this evening into tonight,
strongest over west and north central Lk Superior. Pressure gradient
and winds will weaken for a time Thu aftn and night as a low
pressure trough develops over the Upper Lakes ahead of a low
pressure wave developing over the southern Plains. After this low
pressure wave passes late Thu night/early Fri morning, NW winds up
to 30 kts with gale force gusts to 35 kts will develop on Fri,
strongest over the e half of Lake Superior. NW winds up to 25 kts
will linger into Sat before diminishing to under 15kt late Sat into
Mon as high pres moves across.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLA
LONG TERM...Voss
AVIATION...JLA
MARINE...JLA
Area Forecast Discussion
National Weather Service Norman OK
248 PM CDT WED OCT 5 2016
.DISCUSSION...
Several runs of the operational HRRR indicate a few storms may
develop by late afternoon across western north Texas and far
southern Oklahoma. This will mainly occur along and near a
dryline. Instability and shear will certainly support a few severe
storms with hail and wind.
During evening and overnight, surface winds will back and better
moisture will return to western Oklahoma. This may result in
additional showers and thunderstorms. Overnight, better chances
for showers and storms should shift into northern Oklahoma as
strong low level flow gradually decreases across southern Kansas.
A little uncertain about showers and thunderstorm chances Thursday
morning and early afternoon, but some cloud cover will linger
through the morning.
By late afternoon, a cold front will enter far northern Oklahoma as
a trough lifts from the central Rockies into the central
Plains. Better height falls will remain north of the area, but a
deep enough frontal boundary will result in scattered to numerous
showers and storms along and just behind the front. Moderate
instability ahead of the front will allow for strong to severe
storms, with strong winds and hail.
The front will clear southern Oklahoma and western north Texas by
early morning Friday. Therefore, some rain and showers may linger
near the Red River early but better chances for rain will be
across northern and central Texas.
Mainly dry conditions are expected over the weekend. A trough will
skirt northwestern Oklahoma late in the weekend/early Monday.
Some elevated showers and storms may develop as a result.
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 70 87 54 67 / 30 30 80 20
Hobart OK 69 86 54 68 / 30 40 80 20
Wichita Falls TX 71 89 59 70 / 20 10 70 50
Gage OK 59 87 45 70 / 10 30 40 10
Ponca City OK 70 88 51 67 / 40 50 90 20
Durant OK 71 88 65 75 / 10 10 40 30
&&
.OUN Watches/Warnings/Advisories...
OK...None.
TX...None.
&&
$$