Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/31/16
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
954 PM CDT Sun Oct 30 2016
.EVENING UPDATE...
Similar to last night, fine tuned the WX grid with the latest
information from the hi-res suite. Pushed fog onset time back to
08Z and added coverage details based off trends from last night.
With current obs showing clear skies and very light winds,
radiational cooling effects should be ideal. Have already seen
this as hourly T grids needed significant adjusting in the last
hour.
While the coverage of dense fog may not be as substantial given
the slightly lower dewpoints compared to yesterday...areas still
look likely with some spots likely becoming dense along and east
of the I-35 corridor.
&&
.PREV DISCUSSION... /ISSUED 653 PM CDT Sun Oct 30 2016/
AVIATION.../00Z TAF CYCLE/
VFR conditions prevail across the region as of 2350Z but much lower
ceilings and visibilities are expected to develop overnight through
Monday morning. SREF probabilities, BUFR soundings, and RAP output
of extremely low dewpoint depressions all indicate another round
of LIFR and VLIFR conditions for KAUS/KSSF and KSAT from 10-15Z
Monday morning. These conditions will onset quickly, going from
VFR to IFR or even lower within an hours` time. Dense fog will
again be possible to likely at KAUS/KSSF and potentially near
KSAT. A dense fog advisory may be needed overnight. KDRT will also
decrease to MVFR and IFR as a result of lower ceilings and not so
much lower visibilities at the surface.
All sites will rebound to VFR by mid to late morning Monday as
winds remain light from the south to southeast at 5-10 knots. A
few gusts to 15 knots could occur at KDRT Monday afternoon.
PREV DISCUSSION... /ISSUED 230 PM CDT Sun Oct 30 2016/
SHORT TERM (Tonight through Monday Night)...
Upper air analysis this morning showed a ridge extending from
northwestern Mexico to the northern plains with northwesterly to
northerly flow over Texas. At the surface, a weak pressure
gradient had light winds from the south to southeast. The upper
ridge will move across the region keeping the weather dry during
this period. Morning fog is likely again over the southeastern
part of the CWA Monday. Temperatures will continue well above
normal.
LONG TERM (Tuesday through Sunday)...
Tuesday an upper level trough will dig down along the west coast
while a high closes off over the Gulf. This will bring a short
wave trough through the pattern over Texas which will bring a
chance for showers and thunderstorms. A low will close off at the
southern end of the upper trough over the southwestern states and
this will stall the pattern. This will keep us in an unstable
pattern with POPs each day through the end of the period. A cold
front will move to our CWA Thursday and then stall and dissipate.
This will help focus convection and looks like the day with the
best chance for widespread rain. Rain chances will fall off to
slight for the end of the week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry 63 87 67 85 69 / 0 0 10 50 20
Austin Bergstrom Intl Airport 58 86 65 85 68 / 0 0 10 50 20
New Braunfels Muni Airport 59 86 66 85 68 / 0 0 10 50 20
Burnet Muni Airport 60 84 65 82 67 / 0 0 - 30 20
Del Rio Intl Airport 63 85 66 87 68 / 0 0 0 - 10
Georgetown Muni Airport 58 86 65 84 68 / 0 0 - 40 20
Hondo Muni Airport 60 86 66 86 69 / 0 0 10 20 20
San Marcos Muni Airport 59 85 65 85 67 / 0 0 10 50 20
La Grange - Fayette Regional 60 87 66 85 69 / 0 - - 50 30
San Antonio Intl Airport 62 85 68 84 70 / 0 0 10 40 20
Stinson Muni Airport 63 86 68 86 70 / 0 0 10 40 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Mesoscale/Aviation...Allen
Synoptic/Grids...TB3
Area Forecast Discussion
National Weather Service Grand Forks ND
938 PM CDT Sun Oct 30 2016
.UPDATE...
Issued at 938 PM CDT Sun Oct 30 2016
A few of the sites in the west have seen a drop in visibility, so
included a patchy fog mention for later tonight as dew point
depressions are close to zero and moisture continues to advect
into the area. Adjusted clouds a bit for current satellite trends.
The HRRR and RAP have been slower and drier with bringing showers
in later tonight and tomorrow morning, Delayed the onset of precip
a bit, but will continue to keep isolated POPs for now.
UPDATE Issued at 640 PM CDT Sun Oct 30 2016
Made some minor adjustments to cloud cover. A few spots in south
central ND were seeing some reductions to visibility but have come
back up. Will keep fog mention out for now but will monitor
overnight as we continue to get moisture advecting into the area.
&&
.SHORT TERM...(This evening through Monday)
Issued at 301 PM CDT Sun Oct 30 2016
Moisture advection/return flow will quickly spread clouds across
the region this evening. There is an area of clearing across
eastern North Dakota this afternoon, but expect this to quickly
fill in. The main concern this period will be shower chances. The
upper wave currently crashing onshore the Pacific northwest will
track just north of the International border. As such, the
strongest forcing will remain just north of the the forecast area.
With that said, a strong area of 850mb warm air advection late
tonight should lead to isolated showers quickly propagating across
the region early Monday morning. Then, scattered showers remain
possible near the International border into Monday afternoon with
the widespread rains to the north. Likely a warm day on Monday
ahead of a cold front.
.LONG TERM...(Monday night through Sunday)
Issued at 301 PM CDT Sun Oct 30 2016
Only real forecast concern will be decreasing precipitation chances
with the departure of Monday`s system.
Models continue to be in good agreement with a surface low centered
over the forecast area near the international border to start the
period. As this system propagates to the northeast, any lingering
wraparound precipitation across the far north will move out of the
area by Tuesday morning.
A brief period of zonal flow will then return for Tuesday and
Wednesday across the northern plains. Models continue to depict a
weak wave moving through on Wednesday, but with limited moisture and
the best forcing south of the area, will continue with a dry
forecast. Broad upper ridging will then build into the central CONUS
for the end of the work week and next weekend with no additional
precipitation chances.
Temperatures will remain mild with readings well above average
throughout the period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 640 PM CDT Sun Oct 30 2016
All TAF sites are MVFR, although there is a bit of clearing just
west of the Red River more lower clouds are hot on its heels. Will
continue to keep all sites MVFR throughout the evening. IFR and
lower ceilings will be possible later tonight and tomorrow
morning as moisture continues to advect into the area. Some of the
high resolution model runs are putting out fog along with the
lower ceilings, as well as the NAM guidance. Will keep visibility
restrictions out but will monitor in case there is more stratus
mix down than expected. Some recovery to MVFR and then VFR will be
possible by the end of the period. Winds will stay from the south
to southeast and begin to pick up by tomorrow afternoon with gusts
above 20 kts at times.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...Lee
AVIATION...JR
Area Forecast Discussion
National Weather Service Wilmington OH
1029 PM EDT Sun Oct 30 2016
.SYNOPSIS...
A cold front will push south through the area today and tonight,
bringing a chance of showers. As high pressure travels east through
the Great Lakes Monday into Monday night, the old frontal boundary
will move back northeast as a warm front. Much above normal readings
will then return to the region once again into mid week.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Weak cold front pushing south of the Ohio River will continue
south into the TN Valley by morning. A few lingering showers over
ILN/s southeast counties will come to an end by midnight. Latest
satellite imagery shows low clouds across all Ohio into southern
Michigan and southern Canada. Low level north to northeast flow
at cloud level will keep clouds across ILN/s FA through the night.
Based on clouds have tweaked temperatures a little warmer with
lows from the lower 40s north to the lower 50s far south.
Previous Discussion...
Surface cold front is currently pushing through the CWA and is
just past KDAY with a weak line of showers out ahead. Latest RAP
does have some instability out ahead of the front but it remains
paltry. Latest RAP and HRRR runs seem a bit under done given
latest radar trends but with the shortwave energy mostly heading
north and east of the area think that a weakening trend is likely
in the next couple of hours. Behind the surface cold front surface
high pressure will build into Michigan and work its way into
Ohio. This will allow for low temperatures in the mid 40s.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
During the day Monday the upper level shortwave that was over the
area Sunday will be pushing off the east coast taking the surface
high pressure east with it. As this happens Monday the cold front
that was just south of the area will stall and wash out. As this
happens a warm front will slowly pull north as well. 850 mb
temperatures will hold around 10 degrees C with 1000/850 mb
thicknesses around 1355 m. Have gone ahead and trended high
temperatures closer to low level thicknesses compared to 850 mb
temperatures given the shallow frontal inversion.
Monday night into Tuesday mid-level ridging will build over the
southeastern United States and bulge into the area. 850 mb
temperatures will slowly rise to around 15 degrees C with 1000/
850 mb thicknesses approaching 1400 m across the south. These
numbers would support high temperatures around 80 degrees C on
Tuesday. This would be close to record territory for the beginning
of November.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Mid level short wave energy dropping down across the western Great
Lakes will help push a cold front southeast through the Ohio Valley
late Wednesday night into Thursday. Ahead of this front, broad
southwesterly low level flow will lead to one last unseasonably warm
day On Wednesday with highs mainly in the mid to upper 70s. With
increasing moisture ahead of the front, showers will spread into our
northeast Wednesday night and then across the remainder of the area
Thursday morning. It looks to be a fairly fast moving front though,
so expect to see pcpn begin to taper off from the northwest fairly
quickly through the day on Thursday. The combination of clouds and
some developing CAA will lead to highs in the mid to upper 60s for
Thursday.
The upper level flow will then become more amplified through next
weekend as mid level ridging builds over the Central United States.
The models generally keep any energy dropping down in the northwest
flow off to our northeast through the weekend and this should keep
our area dry through the remainder of the period. Seasonable
temperatures are expected Friday through Sunday with highs in the
upper 50s to lower 60s.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Weak cold front near the Ohio river will continue pushing south
of the TAF sites into the TN Valley by morning. A few showers may
affect KCVG and KLUK early this evening as the front pushes
south. MVFR CIGS in the post frontal environment will persist
through the night. As the low level moisture lowers a period of
IFR cigs will be possible late tonight.
MVFR CIGS will persist through Monday morning with improvement
from the north during the afternoon as surface high pressure
builds into the Great Lakes.
North winds around 10 kts will become northeast overnight and
from the east on Monday.
OUTLOOK...No significant weather is expected.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...Haines
NEAR TERM...Haines/AR
SHORT TERM...Haines
LONG TERM...JGL
AVIATION...AR
Area Forecast Discussion
National Weather Service Lincoln IL
901 PM CDT SUN OCT 30 2016
.UPDATE...
Issued at 900 PM CDT Sun Oct 30 2016
Relatively quiet night across central IL as lingering low cloud
cover remains while a high pressure region moving into the
northern Midwest promotes partial clearing at many locations. Lows
should range from around 45 to 50 degrees and expecting cloud
cover to be pervasive enough to prevent fog from forming at most
locations. However...with lingering low level moisture
characterized by dewpoints in the mid 40s north of I-70 to the mid
50s to the south...any persistent clearing could result in fog
developing. For now, have kept fog mention out of forecast for
most of the area.
&&
.SHORT TERM...(This evening through Monday)
ISSUED AT 254 PM CDT Sun Oct 30 2016
High pressure will build back into the region to start the work
week. Overnight low temperatures chilly and down into the 40s, but
the cloud cover or lack thereof may cause some outliers in the
forecast. Model depiction of the low level moisture profiles is
problematic. HRRR has been introducing some drying from the NE, and
although there has been some erosion of the lowest ceiling over the
southern half of the state...the air to the NE is not necessarily
that dry. Behind the boundary after sunset, low level moisture that
has not yet mixed out may keep cloud cover through the overnight.
NAM and GFS time heights still keeping moisture in place near the
surface...and the RAP 925-850mb layer still plenty of moisture. The
struggle will be between general subsidence with high pressure
building...and the strength of any surface inversion that sets up
and the extend of the stratus development/movement overnight.
Keeping a rather conservative forecast in place with potential to
clear out the southern and eastern skies before the early morning
hours.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 254 PM CDT Sun Oct 30 2016
Strong southerly winds in the low to mid levels of the atmosphere
will bring unseasonably mild air into Illinois Monday night into
Tuesday. Model ave 850mb temps climb to 17-18C Monday night, and
remain in the 14-16C range on Tuesday. The warm air and clouds
Monday night will lead to very mild low temps in the lower 60s.
Clearing skies on Tuesday, especially south of Peoria, should lead
to near record high temps in the lower 80s south of I-74, with upper
70s north of I-74.
An approaching cold front from the NW will bring increasing clouds
into NW Illinois on Tuesday, but the frontal advance is expected to
stall before progressing farther south into central Illinois. The
front will then lift slightly north as a warm front Tuesday night
into Wednesday morning as low pressure advances up along the front
from the central Plains.
The central shortwave will remain north of Illinois as it progresses
into the Great Lakes Wed afternoon and evening. That will finally
drag a cold front through central IL Wed night into Thurs morning.
Forecast soundings continue to show precipitable water values around
1.5" ahead of the front in central IL, which are close to record
climatological levels for early November. The high moisture content
will help fuel MUCAPE values around 400 J/kg later Wed afternoon and
Wed evening. Any storms that develop could produce locally heavy
rainfall and gusty winds, but severe wind/hail is not expected.
The 12z ECMWF has come more into line with the previous GFS and
Canadian solutions of advancing the cold front southeast of our
forecast area Thursday morning, taking rain showers quickly out of
our southeast counties shortly after sunrise. The cold front will
bring cooler conditions, but the air will have a more Pacific origin
instead of central Canada, which will keep daily highs and lows
above normal through next weekend. Highs each day look to remain the
mid to upper 60s, with lows in the mid 40s. No rainfall is expected
from later Thursday morning through next Sunday, under the influence
of stalled high surface pressure and upper level ridging.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 629 PM CDT Sun Oct 30 2016
Bands of cloud cover and areas of clearing affecting central IL
terminals this evening...with cloud bands producing MVFR ceilings.
High pressure moving into the upper Midwest is promoting
subsidence to help produce clearing however moisture trapped at
low levels below subsidence inversion continues to slow clearing.
The result is a challenging cloud cover forecast for
overnight...however models are tending to show several hours of
persistence conditions and have therefore kept ceiling category
unchanged for 6 hours or more. KPIA-KBMI look to have best
potential for improvement due to breaks in the cloud cover to the
north so have improved to VFR category at 6Z there. Winds NW
around 10 kts gradually veering to SE through the forecast period
with a slight increase and some gustiness developing Monday
afternoon.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Onton
SHORT TERM...HJS
LONG TERM...Shimon
AVIATION...Onton
Area Forecast Discussion
National Weather Service North Platte NE
708 PM CDT Sun Oct 30 2016
.SYNOPSIS...
Issued at 153 PM CDT Sun Oct 30 2016
There is a broad ridge from the southern plains through the
central CONUS at mid day. Trough continues along the west coast
and strong Hudson Bay low. At the surface there is a weak cold
front from Long Island through the Texas panhandle then north as a
stationary boundary along the front range of the Rockies.
&&
.SHORT TERM...(This evening)
Issued at 153 PM CDT Sun Oct 30 2016
The main forecast challenges over the near term (this evening and
tonight) are temperatures and wind. The upper ridge axis traverses
the forecast area this evening, transitioning H5 flow to
southwesterly by Monday morning. The morning/afternoon model suite
is in agreement with a potent low level jet developing tonight
across the High Plains. The RAP is the strongest at 850hpa with up
to 50 kts across the Sandhills, with the NAM and GFS showing at
least 40 kts. Forecast soundings show a deep inversion setting up,
which will help keep much of the wind elevated overnight. Some of it
will still mix to the surface, mainly across the Sandhills. Farther
south and in the Platte River Valley, the boundary layer will more
likely decouple. Made little change to min temps overnight as
previous forecast illustrates cooler lows across the south and near
50F across the north. With H85 temps as warm as 15C at 06z and 20C
at 12z, lows are reasonable, if not too cool depending on the amount
of mixing that will occur. Dew points won`t drop off too much
overnight and with a lightening south wind in the Platte River
Valley, some patchy ground fog cannot be ruled out entirely. At this
time, confidence is too low to introduce in the forecast.
.LONG TERM...(Monday through Sunday)
Issued at 153 PM CDT Sun Oct 30 2016
Models coming together in the near term and mid and long term
solutions look reasonable. Have good confidence in the going
forecast. Still have fire weather watch going for western
Nebraska on Monday. See fire weather discussion below. Warm start
to Monday with most lows around 50 over western Nebraska.
Southwest to west winds will increase through the morning and mix
down warm dry air with most highs topping out around 80 aided by
down slope. This will put some records in reach. See climate
discussion below. Very dry air and cold front expected to move
through dry. Lows dropping to around freezing over the northwest
and around forty to the south and east. Upper trough flattens
ridge some but ridge rebounds slightly Tuesday with temperatures
in the 60s and 70s...still above normal. A Pacific airmass will
move east into the central CONUS and dominate the weather pattern
through the end of the week. Dry.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 700 PM CDT Sun Oct 30 2016
The main concerns this aviation package include LLWS and winds.
Latest surface plot and satellite imagery show VFR conditions
across western and north central NEB with high-end VFR (greater
than 7 kft) with a few breaks noted in sky cover.
LLWS conditions are a concern tonight as a southwesterly low
level jet will form over the local forecast area. Thus, LLWS
group is present in the TAF at KLBF and KVTN this evening through
the early morning hours. Upper height of the wind shear layer is
expected to be about 1500 ft with 45 kts and 50 kts forecast at
the top for KLBF and KVTN, respectively. Overnight, winds will not
lessen that much as winds stay southerly 8-15 kts with gusts
exceeding 20 kts in the NEB Sandhills, except in southwest NEB
where light winds are expected. Tomorrow, surface winds will be a
concern. A cold front will move west to east late morning-afternoon
with winds expected to shift from the south-southwest to west.
Windy conditions are expected across portions of the local
forecast area Monday, primarily across the western and central
NEB Sandhills wherein gusts to 30 to 35 kts will be possible.
&&
.FIRE WEATHER...
Issued at 153 PM CDT Sun Oct 30 2016
Dry air will be in place over western Nebraska ahead of a cool
front dropping out of the Dakotas through the day. Strong
southwest to west winds will develop through the morning and
continue through the late afternoon over the Sandhills of Nebraska
north of Interstate 80. Minimum relative humidity is forecast to
be in the upper teens to lower 20 percent ranges. The combination
will result in near critical fire weather conditions. There is
still some question as to lower ranges of relative humidity and
have continued the watch.
&&
.HYDROLOGY...
Issued at 153 PM CDT Sun Oct 30 2016
Minor flood will continue on the North Platte river at North
Platte with increased flows from Lake McConaughy.
&&
.CLIMATE...
Issued at 153 PM CDT Sun Oct 30 2016
Record high for North Platte on October 31st is 82f 1950.
Record high for Valentine on October 31st is 85f set in 1990.
The North Platte record is attainable.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Monday afternoon through Monday evening
for NEZ204-206-208-209.
&&
$$
SYNOPSIS...Power
SHORT TERM...Snively
LONG TERM...Power
AVIATION...ET
FIRE WEATHER...Power
HYDROLOGY...Power
CLIMATE...Power/Snively
Area Forecast Discussion
National Weather Service Lubbock TX
632 PM CDT Sun Oct 30 2016
.AVIATION...
VFR generally expected to prevail as a weak surface ridge
overnight gives way to weak surface low pressure troughing, along
with a dominant upper level high pressure ridge overhead. But
there is a small risk for visibility restrictions from fog to
impact KCDS late tonight until a few hours past daybreak Monday as
the cool dome retreats. The HRRR solution in particular continues
to show some risk of restrictions from around 09z through at least
13z Monday. We have indicated a light fog in the forecast for now
for KCDS in this time interval. Surface southwesterly flow may
become a bit Gusty late M
Area Forecast Discussion
National Weather Service Bismarck ND
415 AM CDT Mon Oct 31 2016
.SHORT TERM...(Today and tonight)
Issued at 415 AM CDT Mon Oct 31 2016
Strong westerly winds and chances for rain across the north will be
the focus of the short term forecast.
The morning challenge will be patchy fog and low stratus in western
and central ND. The 07Z RAP and HRRR are in good agreement on patchy
fog and low stratus lifting northward through the morning. Northern
areas will likely see lingering stratus and fog persisting into the
early afternoon.
Strong westerly wind gusts to around 60 mph are possible in the
southwest, as a deep surface low traverses North Dakota. The latest
guidance shows steep lapse rates and good mixing of upper level
winds down to the surface across portions of southwest and central
North Dakota. Winds will start to increase in the southwest by mid
morning and spread eastward into central and south central areas
through the early afternoon. The strongest winds are expected in
Bowman, Adams, Slope, Hettinger, Stark, Golden Valley, and Billings
counties where a High Wind warning has been issued. Surrounding
counties, into central ND, have been included in a Wind Advisory.
The aforementioned surface low will bring chances for rain,
primarily across the north. Showers will gradually scoot east and
flow northeastward through the day, tapering off through the
overnight hours.
.LONG TERM...(Tuesday through Sunday)
Issued at 415 AM CDT Mon Oct 31 2016
Quiet weather. Above average temperatures and dry conditions
highlight the long term forecast.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 142 AM CDT Mon Oct 31 2016
Low stratus and strong westerly winds will be the focus for the 06Z
TAF period.
Low stratus, with possible periods of fog, will create IFR and LIFR
conditions at each of the sites; though there is uncertainty as to
whether fog will impact KISN. Periods of VLIFR conditions will occur
at KDIK through at least 08Z. Additionally, strong westerly winds
will start around 17Z at KDIK, KBIS, and KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from noon CDT /11 AM MDT/ today to 8 PM CDT /7 PM
MDT/ this evening for NDZ017>021-034-035-042-045-046.
High Wind Warning from 9 AM this morning to 6 PM MDT this
evening for NDZ031>033-040-041-043-044.
&&
$$
AC
Area Forecast Discussion...CORRECTED
National Weather Service North Platte NE
337 AM CDT Mon Oct 31 2016
.SHORT TERM...(Today and tonight)
Issued at 334 AM CDT Mon Oct 31 2016
A strong Pacific cold front is moving into Wrn WY this morning
and should reach Wrn Neb later this morning. The model guidance
suggests breaks in the cirrus today for partly cloudy skies.
Satellite trends seem to support this with a clearing area
forming ahead of the cold front.
The forecast uses a blend of guidance plus bias correction for
highs in the upper 70s to lower 80s. This is in the middle of the
forecast envelope. The super ensemble of 13 models suggests 70s
to near 80 while the unbiased guidance was as warm as mid 80s.
Weak Pacific high pressure will build in tonight supporting lows
in the 30s to lower 40s. Some guidance shows a pocket of upper
20s across Sheridan County.
Winds increase to 20 to 30 mph behind the cold front with gusts
to around 40 mph. A few gusts to 45 mph are possible.
.LONG TERM...(Tuesday through Sunday)
Issued at 334 AM CDT Mon Oct 31 2016
The mild and dry conditions to end the month of October will
carry over into November. There will still be some minor
fluctuations, however highs and lows continue to be above to well
above seasonal norms. Normal temperatures for the first week of
November are 50s for highs and 20s for lows. Will see some ups
and downs but forecast keeps highs at or above 60 and lows above
the freezing mark through the long term period.
Cold air fills in behind the cold front today which will knock
down highs to the 60s for Tuesday and Wednesday. Drier air at the
surface will result in RH values down to the 20s percent however
marginal fire weather conditions at best as winds around or less
than 15 mph.
Mid week low cut off over the deep southwest Conus with weak
ridging across the high plains. This will keep the area dry and
mild. Temps rebound closer to 70 for Thursday and Friday.
By the weekend some questions as to the track of the low pressure
system. The GFS continues to keep the track to the south, however
the EC and the Canadian have lifted the low further north than
previous runs and closer to the area. This could lead to so much
needed moisture by the end of the weekend, although low
confidence will limit pops. Models are in agreement with the mild
temps to remain with 850 mb temps remaining above 5 C so if there
is any precip the form would be liquid.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1130 PM CDT Sun Oct 30 2016
Mostly cloudy skies prevail across western and north central NEB
with high-end VFR (greater than 7 kft) ceilings present. Main
concerns are LLWS conditions rest of tonight-early morning and
then surface winds. VFR flight category conditions are
anticipated over the next 24 hours.
LLWS conditions associated with a low-level jet are expected at
the start of the aviation forecast period across much of western
and north central NEB. VAD wind profiler data denotes a low-level
jet positioned across far western KS to southwest NEB to north
central NEB. KLNX VWP 11 PM CDT data indicates 23 kts @ 200
degrees and 43 kts @ 210 degrees at 250 m and 500 m,
respectively. The upper height of the wind shear layer is
expected to be about 1500 ft with winds up to 50 kts at the top.
These conditions are expected to continue into the early morning
hours, however, LLWS conditions are expected to persist a couple
hours longer over the northern-third of the forecast area.
Otherwise, winds will shift from south-southwest to west as a
cold front advances across the area tomorrow. Moderate to strong
surface winds are expected to develop mid morning through the
afternoon behind the front with good potential for upper level
winds to mix down to the surface. The strongest winds are
expected over the northwestern half of the forecast area wherein
gusts to 30 to 35 kts are anticipated. Surface winds are then
expected to taper off by late evening below 12 kts.
&&
.FIRE WEATHER...
Issued at 334 AM CDT Mon Oct 31 2016
The red flag warning follows minimum humidity values of 20
percent or less. Wind gusts to 35 mph should be common this
afternoon with the greatest threat across Nrn Neb along and north
of Highway 20 west of Valentine where gusts could reach 45 mph.
Elevated fire danger is expected across the Loup river
basins...Loess Plains and Frenchman basin where wind and relative
humidity is not expected to reach critical levels.
The forecast for dew points and wind gusts uses a blend of the
HRRR...RAP and HRRR experimental models plus bias correction.
&&
.CLIMATE...
Issued at 334 AM CDT Mon Oct 31 2016
A few of the record highs for this Halloween holiday could be in
jeopardy
North Platte is 82 F set in 1950.
Valentine is 85 F set in 1990.
Broken Bow is 81 F set in 1965.
Imperial is 82 F set in 1950.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 1 PM CDT /noon MDT/ this afternoon to 7 PM
CDT /6 PM MDT/ this evening for NEZ204-206-208.
&&
$$
SHORT TERM...CDC
LONG TERM...Masek
AVIATION...ET
FIRE WEATHER...CDC
CLIMATE...Masek
Area Forecast Discussion
National Weather Service Norman OK
359 AM CDT Mon Oct 31 2016
.DISCUSSION...
Dense fog this morning is the first concern, then unseasonably
warm weather and elevated fire weather conditions this afternoon
is another concern.
Issue a Dense Fog Advisory through 10 am this morning for most
areas north of an Altus to Anadarko to Seminole line where dense
fog is expected to form in the next few hours. Latest HRRR model
runs seem to have a good handle on this. There is a chance
increasing surface winds may mix some of the fog into stratus,
however some locations will experience 1/4 mile or less
visibility as denoted by some latest observations near Enid, Alva,
and Weatherford. Even a few locations in southern Oklahoma near
Ardmore, Atoka, Wichita Falls, and Lawton may briefly experience
dense fog. Any dense fog should dissipate by 10 am southwest to
northeast as surface winds increase.
This afternoon, unseasonably warm, breezy to windy, and partly to
mostly sunny conditions are expected. Used a blend of guidance
highs mainly in the 80s. Elevated fire weather conditions will
result, especially in northwestern Oklahoma where strongest
surface winds and lowest surface humidity will occur. Conditions
appear to be too marginal for a Red Flag Warning there with
surface relative humidity values just above 20%.
Tonight will be warm and quiet with lows mainly in the upper 50s
and lower 60s. Do not think fog formation will be a problem.
Tuesday, warm and breezy conditions are expected to continue,
though increasing low level moisture may keep highs down a bit
compared to today.
Tuesday night through Thursday, rain chances will increase across
the area, especially Wednesday night as a cold front moves through
the area. Precipitable water values generally 1-1.6" and surface
dewpoints 60-67F will be near climatological maximums for this
time of year. However, mid/upper level forcing and lift near the
front may be rather weak and limit widespread rainfall, especially
with increasing 500 mb heights to around 589 dm which would be
near climatological maximum for this time of year as well. Sufficient
instability would support a few slow moving storms capable of
locally heavy rainfall during this time frame, mainly Wednesday
night near the front. Severe potential appears to be low due to
weak shear. Warm and unusually humid weather will continue on
Wednesday. Drier and cooler air may move in on Thursday north to
south.
Thursday night through Sunday, a brief dry period can be expected
before rain chances return by the weekend. Confidence of rain
remains low and dependent on the movement and timing of a
mid/upper low across the southwestern U.S. Warmer than average
temperatures will likely continue.
MBS
&&
.CLIMATE...
Highs may not be too far from record highs today. Here are the
records for Oklahoma City and Wichita Falls on Monday.
Oklahoma City
October 31...86 set in 1938
Wichita Falls
October 31...92 set in 1934
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 83 61 81 64 / 0 0 0 10
Hobart OK 84 59 81 62 / 0 0 0 10
Wichita Falls TX 87 60 82 64 / 0 0 0 10
Gage OK 89 57 85 60 / 0 0 0 10
Ponca City OK 83 63 84 66 / 0 0 0 10
Durant OK 88 62 81 66 / 0 0 0 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Dense Fog Advisory until 10 AM CDT this morning for OKZ005>008-
011>013-015>031-034>036.
TX...None.
&&
$$
23/17
Area Forecast Discussion
National Weather Service Charleston WV
300 AM EDT Mon Oct 31 2016
.SYNOPSIS...
A front that slipped south of the area Sunday night, will return
as a warm front tonight. Very warm midweek. New cold front with
showers crosses Thursday. Cool, dry Friday into next weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 300 AM Monday...
Widespread low level moisture was in place early this morning, in
the wake of a cold front that had slipped south of the area last
night. The combination pf drier air filtering southward and
daytime mixing is likely to break up the clouds across the north
later this morning.
The clouds will spread northward again tonight, as the front
starts to return north as a warm front. The NAM12 has backed off
on the idea of some rain with the warm front, at least until
beyond tonight, although some upslope drizzle is not entirely out
of the question in the Greenbrier Valley toward dawn.
Temperatures close to guidance and previous, using the MET, NAM12,
HRRR and a short term consensus blend. Today will be much cooler
than the past few given the air mass change and the clouds, but
temperatures may rise a bit late tonight.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
As of 300 AM Monday...
Frontal boundary to the south of the CWA will lift back north on
Tuesday as a warm front, with spotty showers possible as it does so.
Temperatures on Tuesday will warm nicely under southerly flow, with
high temperatures once again climbing into the 70s to lower 80s for
much of the CWA. Wednesday looks to be dry and even warmer, as
heights build out ahead of approaching trough/cold front, which will
affect the area on Thursday. Some slight timing differences between
the models concerning break down of the ridge, and subsequent
arrival of the upper trough and front, but much of Thursday and
Thursday night look to be showery, with isolated thunderstorms
possible.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 300 AM Monday...
Friday will start out with some lingering showers, mainly across the
east, but weather will gradually improve Friday through the weekend
as high pressure gradually nudges its way into the region. Expect
gradually warming temperatures throughout the weekend and into early
next week with temperatures close to normal for this time of year.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
As of 210 AM Monday...
MVFR stratocu in the wake of a cold front that slipper south of
the area will lift and break up Monday morning after daybreak,
although there will also be holes in the overcast overnight. IFR
ceilings in the mountains overnight will be most persistent
south, as drier air creates holes north, MVFR to at times IFR fog
in possible mainly in the mountains overnight into early Monday
morning.
The front will return as a warm front Monday night, bringing some
MVFR stratocu back into the area.
Northerly surface winds will diminish overnight and be light east
to northeast Monday and Monday night, becoming southeast and
strengthening a bit over the mountains Monday night. Moderate
northwest flow aloft will become light northwest Monday morning,
and then light southwest Monday afternoon and night.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: Medium.
ALTERNATE SCENARIOS: Timing of breakup of of MVFR and IFR
overnight and Monday morning may vary from forecast.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 10/31/16
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H H H H H H H H M L L
HTS CONSISTENCY H H H H H H H H H M M L
BKW CONSISTENCY M M M M M M M M M M M L
EKN CONSISTENCY L M M M M L L M M L L M
PKB CONSISTENCY H H H H H H H M M L L M
CKB CONSISTENCY H M M M M H M M M L L M
AFTER 06Z TUESDAY...
IFR river valley fog possible Wednesday morning.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...None.
OH...None.
KY...None.
VA...None.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...TRM
SHORT TERM...SL
LONG TERM...SL
AVIATION...TRM
Area Forecast Discussion
National Weather Service Bismarck ND
952 AM CDT Mon Oct 31 2016
.UPDATE...
Issued at 947 AM CDT Mon Oct 31 2016
Per the 11-13 UTC RAP and 12 UTC NAM BUFR soundings, expanded the
High Wind Warning and the Wind Advisory further east across
southern North Dakota and extended the valid time further into the
evening.
UPDATE Issued at 648 AM CDT Mon Oct 31 2016
No significant changes with the update. Area of precip continues
to move rapidly eastward and should clear our southeastern
counties within the hour. There were a few lightning strikes
associated with this, with a couple in northwest Burleigh county
and a few over the northwest part of the state. Bufkit sounding
for Bismarck indicated around 200 J/Kg of MU CAPE that was
supported by low level convergence as indicated by 850mb
wind field. Also extended patchy fog a little longer as it has
been slow to erode.
&&
.SHORT TERM...(Today and tonight)
Issued at 415 AM CDT Mon Oct 31 2016
Strong westerly winds and chances for rain across the north will be
the focus of the short term forecast.
The morning challenge will be patchy fog and low stratus in western
and central ND. The 07Z RAP and HRRR are in good agreement on patchy
fog and low stratus lifting northward through the morning. Northern
areas will likely see lingering stratus and fog persisting into the
early afternoon.
Strong westerly wind gusts to around 60 mph are possible in the
southwest, as a deep surface low traverses North Dakota. The latest
guidance shows steep lapse rates and good mixing of upper level
winds down to the surface across portions of southwest and central
North Dakota. Winds will start to increase in the southwest by mid
morning and spread eastward into central and south central areas
through the early afternoon. The strongest winds are expected in
Bowman, Adams, Slope, Hettinger, Stark, Golden Valley, and Billings
counties where a High Wind warning has been issued. Surrounding
counties, into central ND, have been included in a Wind Advisory.
The aforementioned surface low will bring chances for rain,
primarily across the north. Showers will gradually scoot east and
flow northeastward through the day, tapering off through the
overnight hours.
.LONG TERM...(Tuesday through Sunday)
Issued at 415 AM CDT Mon Oct 31 2016
Quiet weather. Above average temperatures and dry conditions
highlight the long term forecast.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 947 AM CDT Mon Oct 31 2016
IFR stratus with areas of fog generally along and north of the
I-94 corridor will slowly erode through morning along its southern
extent, but, remain in place across northern North Dakota through
the day with light rain. Very strong winds with westerly gusts of
40-50+ kts will develop across southern North Dakota late this
morning and through the afternoon, continuing into the evening.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 10 PM CDT /9 PM MDT/ this evening for
NDZ017>021-034-035-046.
High Wind Warning until 9 PM CDT /8 PM MDT/ this evening for
NDZ031>033-040>045.
Wind Advisory from 3 PM this afternoon to 10 PM CDT this evening
for NDZ036-037-047-048-050-051.
&&
$$
PJA
Area Forecast Discussion
National Weather Service Lincoln IL
932 AM CDT MON OCT 31 2016
.UPDATE...
Issued at 930 AM CDT Mon Oct 31 2016
Going forecast is largely on track and required only minor edits.
Thin cloud cover is fairly extensive across the area this morning,
with filtered sunshine north of I-72. Areas south of there are
seeing some lower stratus/stratocumulus moving from west to east.
With time, the lower clouds are expected to lift as a warm front
tracks northward into the area, with partly sunny conditions
prevailing by afternoon. Temperatures will surge well into the 60s
by early afternoon, with some 70 degree readings in the far
southeast and southwest CWA.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 322 AM CDT Mon Oct 31 2016
07z/2am surface analysis shows 1025mb high centered over Lake
Huron...while weak cold front has dropped well to the south into
southern Kentucky and the Ozarks. While much of the post-frontal
low cloud cover from yesterday has dissipated, plenty of high clouds
are streaming into the area from the west as evidenced by latest IR
satellite imagery. In addition, low clouds over central/southern
Indiana are edging back westward thanks to E/NE winds in the cloud-
bearing layer. Based on current trajectories, think locations
along/south of I-70 will begin the day under mostly cloudy skies.
Elsewhere around the KILX CWA...partly sunny conditions will be
noted. As the high shifts further away, winds will gradually veer
to the southeast by this afternoon. Due to a continued easterly
component of the wind and ample high cloud cover, have opted to go a
couple of degrees below guidance for high temperatures today.
Readings will mainly be in the middle to upper 60s...with a few
lower 70s across the far SW and SE CWA. With winds becoming more
southerly and increasing due to a tightening pressure gradient,
temperatures tonight will be considerably warmer than in recent
nights...with overnight lows remaining in the upper 50s and lower
60s.
.LONG TERM...(Tuesday through Sunday)
ISSUED AT 322 AM CDT Mon Oct 31 2016
Unseasonably strong 591dm 500mb high over Florida/Georgia will
dominate the weather across the Midwest on Tuesday. With high upper
heights and continued southwesterly low-level flow in place, the
stage will be set for near record high temperatures. Forecast
soundings suggest mixing up to around 875mb...which supports
afternoon highs in the upper 70s and lower 80s.
A cold front will begin to approach from the northwest Tuesday
night: however, most model guidance favors post-frontal precip
developing north of the KILX CWA across Iowa into northern Illinois.
The GFS is a little more robust with the southward extent of the
rain as compared to the ECMWF, so have mentioned low chance PoPs
from the Peoria area northward after midnight. Rain chances will
gradually increase from north to south across the area on
Wednesday, with the main precipitation event taking place
Wednesday afternoon and evening. Surface dewpoints will climb
into the lower 60s, while NAM/GFS precipitable water values reach
near climatological records for early November of 1.50-1.60. Given
the copious amounts of moisture available and strong convergence
along the front, will feature likely PoPs along/west of I-55
during the afternoon...then likely to categorical PoPs across the
board by evening. With MUCAPE values of 400-500J/kg,
thunderstorms will be a good bet as well. The showers and
thunderstorms will come to an end from north to south Wednesday
night into Thursday morning, with storm total rainfall of
0.50-1.00 common across all but the far SE CWA where amounts will
be lower.
Once the front passes, a long stretch of dry weather is expected
from Thursday afternoon through next weekend. Temperatures will
cool somewhat, but will remain 5-10 degrees above normal for this
time of year in the middle to upper 60s.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 637 AM CDT Mon Oct 31 2016
VFR conditions will prevail at all TAF sites next 24hrs. Thin
broken cirrus blankets all TAF sites this morning and based on
satellite trends, will remain over the sites this morning. There
are some MVFR cigs south of the TAF sites and the question is,
will these clouds advect northward toward the sites today. HRRR
model forecast some of these clouds moving northward over the
sites, but believe model is overdoing it so going to take a wait
and see approach and not have MVFR cigs in forecast for now. So
will have broken cirrus at all sites next 24hrs. Winds will be
southeast this morning and then become southerly for the remainder
of the forecast period.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Auten
Area Forecast Discussion...UPDATED
National Weather Service North Platte NE
629 AM CDT Mon Oct 31 2016
.SHORT TERM...(Today and tonight)
Issued at 334 AM CDT Mon Oct 31 2016
A strong Pacific cold front is moving into Wrn WY this morning
and should reach Wrn Neb later this morning. The model guidance
suggests breaks in the cirrus today for partly cloudy skies.
Satellite trends seem to support this with a clearing area
forming ahead of the cold front.
The forecast uses a blend of guidance plus bias correction for
highs in the upper 70s to lower 80s. This is in the middle of the
forecast envelope. The super ensemble of 13 models suggests 70s
to near 80 while the unbiased guidance was as warm as mid 80s.
Weak Pacific high pressure will build in tonight supporting lows
in the 30s to lower 40s. Some guidance shows a pocket of upper
20s across Sheridan County.
Winds increase to 20 to 30 mph behind the cold front with gusts
to around 40 mph. A few gusts to 45 mph are possible.
.LONG TERM...(Tuesday through Sunday)
Issued at 334 AM CDT Mon Oct 31 2016
The mild and dry conditions to end the month of October will
carry over into November. There will still be some minor
fluctuations, however highs and lows continue to be above to well
above seasonal norms. Normal temperatures for the first week of
November are 50s for highs and 20s for lows. Will see some ups
and downs but forecast keeps highs at or above 60 and lows above
the freezing mark through the long term period.
Cold air fills in behind the cold front today which will knock
down highs to the 60s for Tuesday and Wednesday. Drier air at the
surface will result in RH values down to the 20s percent however
marginal fire weather conditions at best as winds around or less
than 15 mph.
Mid week low cut off over the deep southwest Conus with weak
ridging across the high plains. This will keep the area dry and
mild. Temps rebound closer to 70 for Thursday and Friday.
By the weekend some questions as to the track of the low pressure
system. The GFS continues to keep the track to the south, however
the EC and the Canadian have lifted the low further north than
previous runs and closer to the area. This could lead to so much
needed moisture by the end of the weekend, although low
confidence will limit pops. Models are in agreement with the mild
temps to remain with 850 mb temps remaining above 5 C so if there
is any precip the form would be liquid.
&&
.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 629 AM CDT Mon Oct 31 2016
VFR is expected all areas today and tonight.
A Pacific cold front will sweep Western and North Central Nebraska
today. West winds increase to 27023G33KT across Nrn Nebraska this
afternoon and weaken at sunset. Dry air and weak Pacific high
pressure build into the region tonight.
&&
.FIRE WEATHER...
Issued at 334 AM CDT Mon Oct 31 2016
The red flag warning follows minimum humidity values of 20
percent or less. Wind gusts to 35 mph should be common this
afternoon with the greatest threat across Nrn Neb along and north
of Highway 20 west of Valentine where gusts could reach 45 mph.
Elevated fire danger is expected across the Loup river
basins...Loess Plains and Frenchman basin where wind and relative
humidity is not expected to reach critical levels.
The forecast for dew points and wind gusts uses a blend of the
HRRR...RAP and HRRR experimental models plus bias correction.
&&
.CLIMATE...
Issued at 334 AM CDT Mon Oct 31 2016
A few of the record highs for this Halloween holiday could be in
jeopardy
North Platte is 82 F set in 1950.
Valentine is 85 F set in 1990.
Broken Bow is 81 F set in 1965.
Imperial is 82 F set in 1950.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 1 PM CDT /noon MDT/ this afternoon to 7 PM
CDT /6 PM MDT/ this evening for NEZ204-206-208.
&&
$$
SHORT TERM...CDC
LONG TERM...Masek
AVIATION...CDC
FIRE WEATHER...CDC
CLIMATE...Masek
Area Forecast Discussion
National Weather Service Miami FL
1012 AM EDT Mon Oct 31 2016
.UPDATE...
The 12Z MFL sounding indicated 10-20 mph of east northeast winds
from the surface up through 700 mb, with west northwest winds
aloft. With CAPE values less than 1,000 J/KG in place, convection
this afternoon will be limited, if at all. Small scale models,
including the HRRR and WRF continue to advect isolated to
scattered light/mod showers in from the Atlantic through extreme southeast
portions of the peninsula. Have slightly increased pops over this
region to account for similar model to model solutions. As the
band of moisture pushes further south tonight, PWAT values are
forecast to drop below an 1". This will result in diminished
shower activity. Gusty east northeast winds will continue to
affect the region through early this evening, mainly sustained
10-20 mph, with higher gusts, slowly weakening overnight.
&&
.PREV DISCUSSION... /issued 810 AM EDT Mon Oct 31 2016/
AVIATION...
Mainly VFR conditions this morning with the exception of brief
periods of MVFR...bkn/ovc cloud bases 2500 ft msl...over portions
of the southern peninsula. Scattered light showers will be
diminishing through this afternoon. Aft 31/1400Z, expecting east
northeast winds from 060-070 degrees to strengthen to 12-14 KT
with higher gusts. Winds will diminish to below 8 KT aft 01/0600Z
tonight.
PREV DISCUSSION... /issued 337 AM EDT Mon Oct 31 2016/
DISCUSSION...
SHORT TERM (TODAY THROUGH WEDNESDAY)
Few showers/sprinkles exist on radar early this morning over far
southern Miami-Dade county, otherwise skies are generally mostly
cloudy as drier air gradually filters into the region on
northeast winds. Overall synoptic pattern of surface high
pressure centered north of the region over the southern
Appalachians and low pressure over the northwest Carribean Sea
will prevail through the short term, as upper-level ridging
dominates above. The main difference will be the aforementioned
drier air coming in from the western Atlantic, which will allow
for skies to clear and rain chances to diminish. Any shower
activity today generally in the Miami area southward, and will
likely have diminished by evening. Tuesday should be dry day with
some isolated showers working in from the northeast into Palm
Beach county/and potential Atlantic coastal areas on Wednesday
afternoon. Maxima will boost up a few degrees with ample sun, and
highs should reach mid 80s most areas through mid-week. Minima
will range from mid 60s northwest to mid 70s along the Atlantic
coast. Breezy northeast winds will prevail.
LONG TERM (WEDNESDAY NIGHT THROUGH SUNDAY)
Upper-level ridge will erode to the southwest as a shortwave
trough dives southeastward across the eastern CONUS Thursday and
Friday. A cold front is poised to move through by Friday, ushering
in some further dry air along with some slightly cooler
temperatures for the weekend. Showers will be in the isolated to
perhaps scattered category and mainly over eastern half of South
Florida Thursday and Friday, then even less coverage is expected
this weekend. Temperatures behind the front will be near slightly
below normal, with maxima expected around 80 degrees and minima
likely in the 60s areawide.
MARINE...
Small craft operators should continue to exercise caution into
mid-week as northeasterly wind of 15 to 20 knots will prevail.
Advisories may be warranted through Wednesday, before high
pressure weakens to the north and winds subside for Thursday. A
cold front by Friday should shift winds to the northwest, with
increasing winds and seas possible for the weekend.
BEACH FORECAST...
Northeast wind of 15 to 20 knots prevail, and the high risk for
rip currents has been extended through Tuesday. It`s quite
possible this risk will continue into Wednesday.
&&
.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach 84 73 85 75 / 10 10 0 10
Fort Lauderdale 84 73 84 76 / 20 10 0 0
Miami 85 73 85 75 / 20 10 10 10
Naples 87 66 86 67 / 0 0 0 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through Tuesday evening for FLZ168-172-173.
AM...None.
GM...None.
&&
UPDATE...27/JT
DISCUSSION...23/SK
MARINE...23/SK
AVIATION...27/JT
Area Forecast Discussion
National Weather Service Norman OK
632 AM CDT Mon Oct 31 2016
.DISCUSSION...
Aviation discussion for the 12 UTC TAFs is below.
&&
.AVIATION...
The main concern is LIFR conditions near KOKC, KOUN, and KPNC
before 17 UTC. These sites may briefly go below airport minimums
before 14 UTC, so TEMPOs were maintained with these lower
conditions.
Removed IFR or lower conditions at other sites across western
Oklahoma and western north Texas including KSPS and KLAW where
conditions have improved.
After 17 UTC, VFR conditions are expected at all sites.
Towards 12 UTC Tuesday, there is a low chance that MVFR/IFR
conditions with BR returning to a few sites, though chances of
occurrence remain too low to mention.
South to southwest surface winds will become gusty 14-19 UTC then
slowly subside after 23 UTC.
Non-convective low level wind shear may occur at a few sites after
23 UTC, but did not mention due to low confidence of occurrence.
MBS
&&
.PREV DISCUSSION... /issued 359 AM CDT Mon Oct 31 2016/
DISCUSSION...
Dense fog this morning is the first concern, then unseasonably
warm weather and elevated fire weather conditions this afternoon
is another concern.
Issue a Dense Fog Advisory through 10 am this morning for most
areas north of an Altus to Anadarko to Seminole line where dense
fog is expected to form in the next few hours. Latest HRRR model
runs seem to have a good handle on this. There is a chance
increasing surface winds may mix some of the fog into stratus,
however some locations will experience 1/4 mile or less
visibility as denoted by some latest observations near Enid, Alva,
and Weatherford. Even a few locations in southern Oklahoma near
Ardmore, Atoka, Wichita Falls, and Lawton may briefly experience
dense fog. Any dense fog should dissipate by 10 am southwest to
northeast as surface winds increase.
This afternoon, unseasonably warm, breezy to windy, and partly to
mostly sunny conditions are expected. Used a blend of guidance
highs mainly in the 80s. Elevated fire weather conditions will
result, especially in northwestern Oklahoma where strongest
surface winds and lowest surface humidity will occur. Conditions
appear to be too marginal for a Red Flag Warning there with
surface relative humidity values just above 20%.
Tonight will be warm and quiet with lows mainly in the upper 50s
and lower 60s. Do not think fog formation will be a problem.
Tuesday, warm and breezy conditions are expected to continue,
though increasing low level moisture may keep highs down a bit
compared to today.
Tuesday night through Thursday, rain chances will increase across
the area, especially Wednesday night as a cold front moves through
the area. Precipitable water values generally 1-1.6" and surface
dewpoints 60-67F will be near climatological maximums for this
time of year. However, mid/upper level forcing and lift near the
front may be rather weak and limit widespread rainfall, especially
with increasing 500 mb heights to around 589 dm which would be
near climatological maximum for this time of year as well. Sufficient
instability would support a few slow moving storms capable of
locally heavy rainfall during this time frame, mainly Wednesday
night near the front. Severe potential appears to be low due to
weak shear. Warm and unusually humid weather will continue on
Wednesday. Drier and cooler air may move in on Thursday north to
south.
Thursday night through Sunday, a brief dry period can be expected
before rain chances return by the weekend. Confidence of rain
remains low and dependent on the movement and timing of a
mid/upper low across the southwestern U.S. Warmer than average
temperatures will likely continue.
MBS
CLIMATE...
Highs may not be too far from record highs today. Here are the
records for Oklahoma City and Wichita Falls on Monday.
Oklahoma City
October 31...86 set in 1938
Wichita Falls
October 31...92 set in 1934
&&
.PRELIMINARY POINT TEMPS/POPS...
Oklahoma City OK 83 61 81 64 / 0 0 0 10
Hobart OK 84 59 81 62 / 0 0 0 10
Wichita Falls TX 87 60 82 64 / 0 0 0 10
Gage OK 89 57 85 60 / 0 0 0 10
Ponca City OK 83 63 84 66 / 0 0 0 10
Durant OK 88 62 81 66 / 0 0 0 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...Dense Fog Advisory until 10 AM CDT this morning for OKZ005>008-
011>013-015>031-034>036.
TX...None.
&&
$$
23/17/17
Area Forecast Discussion
National Weather Service Charleston WV
1022 AM EDT Mon Oct 31 2016
.SYNOPSIS...
A front that slipped south of the area last night, will return as
a warm front tonight. Very warm midweek. New cold front with
showers crosses Thursday. Cool and dry Friday into next weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
1040 AM Update...Just made minor changes to sky cover based on
current visible imagery and observations. Will still likely see
clouds start to mix out in the next few hours, but this time of
year with the lower sun angle they tend to linger a bit longer, so
I have delayed them scattering out until early this afternoon.
As of 640 AM Monday...
Forecast on track with clearing line about 50 miles north of the
forecast area.
As of 300 AM Monday...
Widespread low level moisture was in place early this morning, in
the wake of a cold front that had slipped south of the area last
night. The combination pf drier air filtering southward and
daytime mixing is likely to break up the clouds across the north
later this morning.
The clouds will spread northward again tonight, as the front
starts to return north as a warm front. The NAM12 has backed off
on the idea of some rain with the warm front, at least until
beyond tonight, although some upslope drizzle is not entirely out
of the question in the Greenbrier Valley toward dawn.
Temperatures close to guidance and previous, using the MET, NAM12,
HRRR and a short term consensus blend. Today will be much cooler
than the past few given the air mass change and the clouds, but
temperatures may rise a bit late tonight.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
As of 300 AM Monday...
Frontal boundary to the south of the CWA will lift back north on
Tuesday as a warm front, with spotty showers possible as it does so.
Temperatures on Tuesday will warm nicely under southerly flow, with
high temperatures once again climbing into the 70s to lower 80s for
much of the CWA. Wednesday looks to be dry and even warmer, as
heights build out ahead of approaching trough/cold front, which will
affect the area on Thursday. Some slight timing differences between
the models concerning break down of the ridge, and subsequent
arrival of the upper trough and front, but much of Thursday and
Thursday night look to be showery, with isolated thunderstorms
possible.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 300 AM Monday...
Friday will start out with some lingering showers, mainly across the
east, but weather will gradually improve Friday through the weekend
as high pressure gradually nudges its way into the region. Expect
gradually warming temperatures throughout the weekend and into early
next week with temperatures close to normal for this time of year.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
As of 640 AM Monday...
MVFR stratocu in the wake of a cold front that slipper south of
the area last night, will lift and break up from north to south
this morning. IFR ceilings in the mountains obscuring ridges will
also thin and lift out this morning.
The front will return as a warm front tonight, bringing some MVFR
stratocu back into the area.
Light northeast surface winds will become southeast in the
mountains tonight and strengthen a bit over the ridges. Light
northwest flow aloft this morning will become light southwest this
afternoon and tonight.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY...
FORECAST CONFIDENCE: Medium.
ALTERNATE SCENARIOS: Timing of breakup of of MVFR and IFR
this morning may vary from forecast, as may its reforming tonight.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 12 13 14 15 16 17 18 19 20 21 22 23
EDT 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
CRW CONSISTENCY H H H H H H M H H M M M
HTS CONSISTENCY H H H H H L H H L L M M
BKW CONSISTENCY M L M H M H H H H L L L
EKN CONSISTENCY H H H M M H H H H M M M
PKB CONSISTENCY H H H H M H H H H M M M
CKB CONSISTENCY H H H M M H H H H M M M
AFTER 12Z TUESDAY...
IFR river valley fog possible Wednesday morning.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...None.
OH...None.
KY...None.
VA...None.
&&
$$
SYNOPSIS...TRM/SL
NEAR TERM...TRM/MPK
SHORT TERM...SL
LONG TERM...SL
AVIATION...TRM
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
1004 AM EDT Mon Oct 31 2016
.SYNOPSIS...
14Z water vapor and H4 RAP analysis shows a synoptic pattern that
will keep our dry and uneventful fall weather going for several
more days to come. There is a progressive and active northern
stream jet arriving over the Pacific coast before crossing the
northern Plains/Great Lakes...however our forecast region will be
protected from this energy through the short term forecast period
by strong mid/upper level ridging along the northern Gulf Coast
that will be slowly building eastward over the Florida peninsula
through the next 12-24 hours. Signs of the approaching influence
of the ridge can be seen in wv imagery...as a sharp moisture
gradient aloft has been progressively pushed southward this
morning...with the main gradient now lying to the south Lee
County. This upper moisture gradient is due to the fact that the
ridge axis has been building over the I-10 corridor first
today...and is now beginning to slowly expand south. The expansion
south is forcing the exit eastward of southern stream jet energy
currently over the southern half of the Florida peninsula. PW
values off the 12Z KTBW RAOB are now around 0.8"...compared to
yesterday at this time when PW values were still over 1.5". The
bulk of the atmospheric column has dried out significantly since
Sunday.
The story closer to the surface is one dominated by high pressure
ridging down along the eastern seaboard into northern Florida/NE
Gulf of Mexico. Our position along the southern periphery of this
circulation is providing a steady east/NE flow across the Florida
peninsula. The gradient becomes tighter the further south down the
peninsula one travels...and hence so will be potential for gusty
diurnal winds the rest of the daylight hours. North of the I-4
corridor...the gradient relaxes quickly. This relaxed
gradient...combined with the building deep layer suppression from
the upper ridge allowed a fairly extensive area of dense fog to
develop to the north of I-4 this morning. With diurnal mixing now
underway...this area of fog is shrinking and lifting rapidly. The
dense fog advisory that was in effect for the nature coast zones
was allowed to expire at 9AM...and no further fog concerns are
anticipated the remainder of the day. Late tonight...fog concerns
may come back...but will discuss that in the short term section
below.
&&
.SHORT TERM (Rest of Today through Tuesday)...
The remainder of today looks dry and seasonably warm. Will take
another hour or so to completely burn off the fog/lower stratus
across parts of the Nature coast...but visible satellite shows
this area shrinking rapidly. By midday...mostly sunny skies will
prevail for all areas. Large scale atmospheric suppression will
only increase through the afternoon...allowing the column to
further dry out above 5KFT. The easterly winds off the Atlantic
will keep a bit of moisture trapped under 850mb...but not deep
enough to support any showers...and only deep enough to support a
few shallow cumulus through early afternoon. The deeper into the
afternoon we get...it is likely that we will mix above the
moisture level...and any cumulus we do see out there will
evaporate. The building upper ridge will allow things to get
rather "toasty" for the final day of October. Unlikely we will see
any record temps today...but won`t be too far off either. Current
forecast is looking for high temperatures in the middle/upper 80s.
Average high temperatures are commonly in the lower 80s across
central and northern portions of the state...and middle 80s
further south. Record temperatures within a degree or 2 of around
90.
Tonight...Upper ridge really takes control over the
peninsula...with H5 heights approaching 590DM in many spots by
dawn. While not unheard of...that is still fairly impressive for
November 1st. There is a threat for some fog to the north of the
I-4 corridor late night...especially with the upper ridge firmly
overhead. However...there are also some indications that the lower
level gradient will tighten just enough to prevent as widespread
boundary layer decoupling as we saw this morning. Sub-1000mb winds
north of I-4 this morning were generally 5kts or less...with many
NWP members showing 5-10kts between 06Z-12Z tomorrow morning. If
the GFS is correct...showing 10-14kts at 1000mb by 12Z
Tuesday...then not much fog will be around our zones. With all
this in mind...will allow patchy fog in the grids...expecting more
protected and low-lying areas to support some fog...but leave out
higher coverage or mention of dense fog until potential negative
factors become more clear. Forecasting boundary layer decoupling
when conditions are not ideal...is often a difficult task in any
one particular location...as this level is parameterized in NWP
guidance and land-surface input is generally broad compared to
realistic gradients in vegetation/urbanization etc. Just have to
do the best with the data you have...and rely considerably on
local knowledge and past forecast experiences during similar
conditions.
Tuesday...More of the same. Dry and warm...with abundant sunshine
(after any patchy morning fog burns off). Previous shift bumped
high temperatures up a degree or two compared to MOS given the
strength of the upper ridge and drier soil conditions now in
place. Think this was a good forecast decision and will not be
making much changes to the forecast high temps tomorrow. Very
possible a few areas may flirt with record highs...although likely
to fall a couple of degrees short at most spots. Even with that
said...Widespread upper 80s along the I-75 corridor...with middle
80s across eastern Polk/Highlands counties where the influence of
the Atlantic waters due to the easterly flow will be greater.
&&
.LONG TERM...
A ridge aloft will remain centered over the Gulf of Mexico and
Florida Tuesday night through Wednesday and then will shift
westward on Thursday as a trough digs toward the eastern seaboard.
At the surface, high pressure will generally remain centered just
north of the area through Thursday as an area of low pressure
moves into the northeast and brings its associated cold front into
the southeast. This front is still forecast to pass through the
Florida peninsula late Friday, with very little in the way of rain
chances. Winds will become northwest and then northeast Friday
into Saturday and will likely be gusty at times, especially over
the coastal waters. High pressure will build in behind the front
for the weekend and early next week. This will give us another
very pleasant weekend and start of the next work week, with drier
air in place and high temperatures generally in the 70s.
&&
.AVIATION (31/12z - 01/12Z)...
VFR conditions prevail through the period for all terminals.
Light to moderate northeast winds in place across the region.
Winds become gusty from 15z through 22z, then decrease by sunset.
Patchy/Areas of fog (locally dense) should re-develop once again
after midnight, but is currently anticipated to generally remain
north of the I-4 corridor terminals.
&&
.MARINE...
Easterly flow will dominate the marine forecast the next several
days as high pressure remains to the north of the region. The
position of the ridge to our north will support enhanced surges of
easterly flow developing during the evening hours. Good potential
for winds to reach cautionary levels for many spots by later this
evening into the overnight hours...and then again Tuesday night.
This general pattern should be expected to continue through
Wednesday night before our next cold front approaches from the
north Thursday night into Friday.
&&
.Preliminary Point Temps/PoPs...
TPA 85 66 86 69 / 0 0 0 10
FMY 87 66 86 67 / 0 0 0 0
GIF 86 64 86 66 / 0 0 10 10
SRQ 85 66 85 67 / 0 0 0 10
BKV 87 60 87 63 / 0 0 0 10
SPG 83 69 83 70 / 0 0 0 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...None.
Gulf waters...None.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE...Mroczka
LONG TERM...Carlisle
Area Forecast Discussion
National Weather Service La Crosse WI
308 PM CDT Mon Oct 31 2016
.SHORT TERM...(This evening through Tuesday)
Issued at 308 PM CDT Mon Oct 31 2016
Latest 19z surface analysis indicated low pressure over eastern
North Dakota. Out ahead of the low pressure system...tight
pressure gradient has produced sustained winds of 15 to 20 knots
and gust 25 to 30 knots per 19z metars.
Surface low will push into southern Ontario Canada tonight. Near
surface boundary layer moisture and strong inversion over forecast
area will allow for low stratus deck of clouds to linger or expand
back into the region. The 31.12z NAM and 31.15z RAP bufkit
soundings suggest vertical motion/lift in the saturated layer
mainly along and north of the Interstate 94 corridor. This will
result in some areas of drizzle across central Wisconsin this
evening. Have introduced area of drizzle across this area this
evening.
A surface cold front tracks into eastern Great Lakes Region by
12z Tuesday and surface ridge builds into eastern Minnesota and
western Wisconsin during the day Tuesday. Subsidence underneath
surface ridge and drier air advecting into the forecast
area...will allow for stratus deck of clouds to erode from west to
east across the forecast area early Tuesday morning.
.LONG TERM...(Tuesday night through Monday)
Issued at 308 PM CDT Mon Oct 31 2016
Tuesday Night through Thursday...Stalled frontal boundary lying
across southern WI, northern IL, and eastern IA will be worked on
by more shortwave trough energy Wednesday. Having the front aligned
with the southwest flow allows for frontogenetic forcing at various
levels sloping northwest. While the rain chances have been
consistent in the forecast decreasing from 60-70 percent south, to
small chances near I-90, have some concerns that these will all need
to be raised as we approach Wednesday. However, there is quite dry
air in the lowest levels on the north side of the boundary tempering
the desire to raise rain chances at this time. Drying will then move
in for a sunny Thursday as the northwest flow shortwave trough moves
through with a brief and weak cold front.
Upper-level ridging over the north-central CONUS along with broad
surface high pressure will be the dominant weather influence
Thursday night through Sunday. With the ridge axis centered more
over the Northern High Plains through Saturday, our area stays under
northwesterly flow aloft. The 31.12Z GFS brings a shortwave trough
southeastward through Wisconsin late Saturday, with the 31.00Z ECMWF
also hinting at a disturbance over Iowa during this timeframe.
However, a lack of moisture and low-level forcing should preclude
any precipitation from developing. The upper-level ridge axis passes
through on Sunday and moves off to our east as a more potent upper-
level trough moves from the Pacific Northwest towards the Northern
Plains on Monday. The GFS and ECMWF differ slightly on the timing of
this feature, with the ECMWF being more progressive. The ECMWF
brings a surface trough into our area as early as Monday afternoon,
while the GFS keeps the best forcing well off to our west. Will
introduce low chances for rain across our western areas Monday
afternoon.
Temperatures are looking to remain very mild, with highs around 10
degrees above normal. While nights may be cooler under the influence
of high pressure, there is no clear signal for below freezing
temperatures on any night through the forecast period.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1240 PM CDT Mon Oct 31 2016
Main taf concerns are IFR/MVFR conditions at RST/LSE taf sites
into tonight...and windy conditions this afternoon. Near surface
boundary layer moisture and a strong inversion has produced low
stratus deck of clouds/IFR conditions across parts of southeast
Minnesota and northeast Iowa...with MVFR conditions along and east
of the Mississippi River. Surface front over the western Dakotas
will move into central Wisconsin by 12z and erode the low stratus
deck of clouds west to east across the area. Expect the IFR/MVFR
conditions to continue at both RST/LSE taf sites through 07z to
10z Tuesday. There are hints LIFR conditions are possible at RST
taf site this evening. Confidence at this time is low to include
in the taf. Tight pressure gradient across the area ahead of the
surface front...will continue to allow sustained winds of 15 to 25
knots with gust of 23 to 35 knots through 22z Monday. Gradient
slackens around 00z and winds will diminish to around 10 knots by
03z Tuesday.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
SHORT TERM...DTJ
LONG TERM...BAUMGARDT/MH
AVIATION...DTJ
Area Forecast Discussion
National Weather Service Bismarck ND
538 PM CDT Mon Oct 31 2016
.UPDATE...
Issued at 526 PM CDT Mon Oct 31 2016
Updated forecast to add some fog over the north central portion of
the state. Visibilities here in the 1 to 3 mile range, but should
improve by around mid evening as the surface low moves east and
winds become northwest and increase. Also adjusted pops based on
latest radar analysis.
Farther south, there are some winds gusting around 40 to 45 mph in
the southwest and far south central where skies have cleared late
this afternoon. Looks like surface low took a little more of a
southerly track compared go guidance last night. Thus we never
realized our gust potential. Will take a look at 6 pm Obs and
unless we see something way out of line, will likely cancel by 7
pm. This should allow gusty winds far south to settle a bit. There
is a secondary pressure bubble tracking across the area later
tonight and may keep winds breezy to even windy a times but expect
them to remain below advisory criteria. Remaining updated products
will be sent shortly.
&&
.SHORT TERM...(This evening through Tuesday)
Issued at 233 PM CDT Mon Oct 31 2016
Very strong winds late this afternoon and evening south central
and southeast highlight the short term forecast.
No changes were made at this time to the ongoing High Wind Warning
and Wind Advisory across southwest and south central North Dakota.
The strongest winds through 19 UTC have been in the cloud free
area across the far southwest and south central where insolation
has allowed for greater mixing and momentum transfer. Visible
satellite trends through 1930 UTC suggest continued slow erosion of
the stratus deck between I-94 and ND Highway 200, to allow for
much stronger winds to impact these areas through the evening. The
12 UTC NAM/GFS and the 16-18 UTC RAP BUFR soundings suggest
50-60kts at the top of the mixed layer across the southwest, and
45-50 kts across the south central and James River Valley.
Momentum transfer aided by cold air advection behind the surface
low departing into northwest Minnesota and modest isallobaric
forcing supports the current spatial and temporal placement of
wind headlines at this time.
.LONG TERM...(Tuesday night through Monday)
Issued at 233 PM CDT Mon Oct 31 2016
Above normal temperatures highlight the extended forecast.
The 00 UTC global suites are in agreement on an upper level ridge
building into the Northern Plains late Wednesday, and remaining in
place through the extended forecast period. This supports a
continued stretch of above normal temperatures to begin November
with widespread highs in the upper 50s and 60s.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 526 PM CDT Mon Oct 31 2016
MVFR-IFR ceilings KISN to KMOT tonight improving Tuesday morning.
VFR to occasional MVFR ceilings KDIK-KBIS-KJMS tonight also
improving Tuesday morning.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 10 PM CDT /9 PM MDT/ this evening for
NDZ017>021-034>037-046>048-050-051.
High Wind Warning until 9 PM CDT /8 PM MDT/ this evening for
NDZ031>033-040>045.
&&
$$
UPDATE...TWH
SHORT TERM...AYD
LONG TERM...AYD
AVIATION...twh
Area Forecast Discussion
National Weather Service San Francisco Bay Area
221 PM PDT Mon Oct 31 2016
.SYNOPSIS...An approaching frontal system will bring widespread
rain showers to much of the region this afternoon and evening
along with a slight chance of thunderstorms across the North Bay.
Lingering showers will then be possible into Tuesday morning with
drying conditions by Tuesday night. A warming and drying trend is
then expected for the remainder of the workweek.
&&
&&
.DISCUSSION...as of 02:20 PM PDT Monday...KMUX radar imagery is
showing more returns over the North Bay indicating possible light
rain. There have been a few obs in the North Bay picking up a
hundredth or two this afternoon. The light showers are likely
associated with pre-frontal warm air advection ahead of the main
cold front. Latest satellite continues to show a nice spinning low
off the NorCal Coast. There has been a decent amount of lightning
near the low and along the cold front since last night as well.
For the rest of the afternoon/evening...The sfc low and cold
front will continue to approach the coast and eventually move
inland this evening. That being said, will keep previous forecast
going. 12z WRF and latest HRRR model show an increase in
shower/rain activity through this evening. There is still a chance
for thunderstorms as well. Best chance for thunderstorms and
appreciable rainfall will be north of the Golden Gate. South of
the Golden Gate, precip chances decrease with no mention of
thunderstorms. One other item of note, freezing level lowers to
6-7k feet. If storms do develop small hail will be possible given
the colder air aloft.
If you happen to have outdoor activities this evening, plan head for
inclement weather. Additionally, with the threat of thunderstorms
make sure to have a place to seek shelter if a storm develops.
Precipitation will diminish through the night with a few
lingering showers possible early Tuesday. Storm total rainfall
through Tuesday will be greatest over the North Bay 0.5-1", south
of the Golden Gate a few hundredths to 0.25". The caveat would be
locally higher amounts if thunderstorms develop.
Behind the cold front, high pressure is forecast to build over the
region bringing drier weather Tuesday afternoon through Thursday.
Medium range models bring a weak boundary into NorCal
Wednesday/Thursday, but the Bay Area looks dry with the ridge
blocking the front. However, do have a mention for schc of showers
over the northern coastal waters. The ridge begins to shift
eastward on Friday as another storm system approaches the West
Coast. Confidence is increasing as most medium range models
indicate precip Saturday night into Sunday for the North Bay.
Therefore, will keep the a slight chance to chance of rain for the
upcoming weekend.
&&
.AVIATION...as of 11:06 AM PDT Monday...An upper level trough and
associated surface cold front are still forecast to move
southeastward over the area this afternoon and early evening.
Visible satellite shows a mixture of high and lower level clouds
moving into the Greater Bay Area at this hour. Some instability
ahead of the front could spark up a thunderstorm or two over the
North Bay this afternoon and early evening. This instability may
potentially spread into the Bay Area early tonight, but confidence
is low on thunderstorm development. The front is progged to move
through the North Bay around 21z, and the Bay Area closer to 00z.
The front then weakens and falls apart as it reaches the Monterey
Bay area, and therefore winds will not be quite as strong. Southwest
winds will be gusty along and ahead of the front, gusting around
25 kt in the Bay Area and points northward. Winds will subside
behind the front. Areas of showers, some moderate to heavy, will
begin in the North Bay and shift southward through the evening.
Cigs will generally be VFR this afternoon, but MVFR cigs quickly
advect in from the northwest late this afternoon into the early
evening with the rain.
Vicinity of KSFO...VFR, then MVFR later this afternoon. Light to
moderate showers arrive as early as 22z, becoming more widespread this
evening. Winds increase and become gusty out of the southwest by
21-22z. Gusts around 25 kt possible.
SFO Bridge Approach...Similar to KSFO.
Monterey Bay Terminals...Mainly VFR today. Showers arrive by early
evening. Generally light to moderate southwest/west winds, 10-12
kt this afternoon.
&&
.MARINE...as of 09:24 AM PDT Monday...A cold front will sweep
southeastward over the coastal waters and bays today. conditions
will deteriorate late this morning and afternoon with heavy
showers and possibly a few thunderstorms with small hail. high
pressure will rapidly build back in over the area beginning
tuesday. large nw swell is expected on thursday.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.Tngt...SCA...Pt Arena to Pt Reyes 0-10 nm until 6 PM
SCA...Pt Arena to Pigeon Pt 10-60 nm until 6 PM
SCA...Pt Reyes to Pigeon Pt 0-10 nm until 3 AM
SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm until 11 PM
&&
$$
PUBLIC FORECAST: MM
AVIATION: BAM
MARINE: BAM
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Area Forecast Discussion
National Weather Service Sacramento CA
236 PM PDT Mon Oct 31 2016
.SYNOPSIS...
Halloween precipitation across interior NorCal tonight. Drier
weather returns for the rest of the week with the next chance
of wet weather this weekend.
&&
.DISCUSSION...
Another, but weaker Pacific storm is moving inland today. Radar
imagery at 2 pm showed light to moderate showers impacting the
Northwest CA coast, moving over the Coastal Range and into the
northern Sacramento valley. The big question for tonight is how
will rain and snow impact Halloween tonight. Latest HRRR (high
resolution) model suggests that the eastern slopes of the Coastal
Range (Alder Springs, Lakeport, Clear Lake) will see rain starting
between now to 4 pm. Rain should arrive in the Redding-Red Bluff
area between 3 to 5 pm...Chico between 4 to 6 pm
...Marysville-Yuba City area between 5 to 7 pm...Sacramento
between 6 to 7 pm. Stockton & Modesto could be hit or miss if
they get any rain, but if they do see showers it would probably be
very light, brief and after 7 pm. Rain amounts range from very
light in the Stockton area up to a quarter of an inch around
Redding between 5-10 pm.
The HRRR updates every hour and each new run flip-flops as to
whether areas south of Marysville will see showers or not. Bottom
line, make sure all your trick-or-treaters wear warm clothing and
have umbrellas. Motorists should be extremely cautious driving,
especially if roads are slick and visibility is reduced from rain.
Looking towards the Western Sierra foothills and mountains:
expect the brunt of rain/snow to start impacting that region
after 6 pm with snow levels around 6000 ft. Rain and snow over the
Sierra could linger into early Tuesday morning. Rain amounts
should range 0.20 to about a half inch in the foothills with
higher amounts above 3000 ft. Snow amounts will vary between 2-4
inches around 6000 ft up to 8 inches over the highest peaks of the
Sierra. Any mountain travelers tonight should check CalTrans road
conditions because delays and chain controls are likely.
This storm shifts east into the Great Basin Tuesday. Upper
ridging then builds over NorCal providing drier weather with minor
warming through the mid-week period.
JBB
&&
.EXTENDED DISCUSSION (Friday THROUGH Monday)
Dry weather continues into Friday and early Saturday as high
pressure shifts eastward. High temperatures will remain near
normal through this stretch.
The next weather system then approaches northern California Saturday
and Sunday. The GFS is more bullish with precipitation than the
ECMWF or Canadian. With medium confidence, we`ve maintained
chances of precipitation across the region. Snow level will be
high with this system but could fall to 7000 feet late Sunday.
Drier weather settles in again Monday as high pressure rebuilds
over California.
&&
.AVIATION...
Next weather system will move across the region tonight. VFR/MVFR
conditions are expected for the Valley, with IFR/LIFR conditions
continuing over the mountains. South winds expected to increase to
10-16 kt in advance of this system.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 8 AM PDT Tuesday for West Slope
Northern Sierra Nevada-Western Plumas County/Lassen Park.
&&
$$
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
256 PM EDT Mon Oct 31 2016
.SYNOPSIS...
19Z water vapor and H4 RAP analysis shows a synoptic pattern that
will keep our dry and uneventful fall weather going for several
more days to come. There is a progressive and active northern
stream jet arriving over the Pacific coast before crossing the
northern Plains/Great Lakes...however our forecast region will be
protected from this energy through the short term forecast period
by strong mid/upper level ridging along the northern Gulf Coast
that will be slowly building eastward over the Florida peninsula
through the next 12-24 hours. Signs of the approaching influence
of the ridge can be seen in wv imagery...as a sharp moisture
gradient aloft has been progressively pushed southward through the
day...with the main gradient now lying well to the south Lee
County. This upper moisture gradient is due to the fact that the
ridge axis has been building over the I-10 corridor first
today...and is now slowly expand south. The expansion south is
forcing the exit eastward of southern stream jet energy currently
over the southern half of the Florida peninsula. PW values off the
12Z KTBW RAOB dropped to around 0.8"...compared to yesterday at
this time when PW values were still over 1.5". The bulk of the
atmospheric column has dried out significantly since Sunday.
The story closer to the surface is one dominated by high pressure
ridging down along the eastern seaboard into northern Florida/NE
Gulf of Mexico. Our position along the southern periphery of this
circulation is providing a steady east/NE flow across the Florida
peninsula. The gradient becomes tighter the further south down the
peninsula one travels...and hence so will be potential for gusty
diurnal winds the rest of the daylight hours. North of the I-4
corridor...the gradient relaxes quickly.
&&
.SHORT TERM (Rest of today through Tuesday)...
The remainder of today will remain dry and seasonably warm. The
easterly winds off the Atlantic have allowed some moisture
trapped under 850mb over the far southern zones...but not deep
enough to support any showers...and only deep enough to support a
few-sct shallow cumulus over Charlotte/Lee counties. The deeper
into the afternoon we get...it is likely that we will mix above
the top of the moisture level...and any cumulus we do see out
there will evaporate. The building upper ridge has allowed things
to get rather "toasty" for the final day of October. Looking at
many observations in the middle to upper 80s across the region.
Unlikely we will see any record temps today based on current
readings and remaining time for heating...but won`t be too far off
either. Average high temperatures are commonly in the lower 80s
across central and northern portions of the state...and middle 80s
further south. Record temperatures within a degree or 2 of around
90.
Tonight...Upper ridge really takes control over the
peninsula...with H5 heights approaching 590DM in many spots by
dawn. While not unheard of...that is still fairly impressive for
November 1st. There is a threat for some fog to the north of the
I-4 corridor late night...especially with the upper ridge firmly
overhead. However...NWP continues to suggest that the lower level
gradient will be tighten tomorrow morning that it was this past
morning...and may become just strong enough to prevent as
widespread boundary layer decoupling as we saw this morning. Sub-
1000mb winds north of I-4 this morning were generally 5kts or
less...with many NWP members showing 5-10kts between 06Z-12Z
tomorrow morning. The GFS for several runs now has shown...10+kts
at 1000mb by 12Z Tuesday. If these predictions do occur...we will
not see much fog in our zones. The reality will likely be
somewhere between what was seen this past morning...and too much
wind for fog. The SREF would still suggest some fog...especially
up toward Citrus/Levy/Sumter counties. With all this in
mind...will allow patchy fog in the grids...expecting more
protected and low-lying areas to support the fog...but leave out
higher coverage or mention of dense fog. Forecasting boundary
layer decoupling when conditions are not ideal...is often a
difficult task in any one particular location...as the boundary
layer is parameterized in NWP guidance and land-surface input is
generally broad compared to realistic gradients in
vegetation/urbanization etc. Just have to do the best with the
data you have...and rely considerably on local knowledge and past
forecast experiences during similar conditions.
Tuesday...More of the same. Dry and warm...with abundant sunshine
(after any patchy morning fog burns off). Previous shift bumped
high temperatures up a degree or two compared to MOS given the
strength of the upper ridge and drier soil conditions now in
place. Think this was a good forecast decision and did not make
much in the way of changes to the forecast high temps tomorrow.
Very possible a few areas may flirt with record highs...although
likely to fall a couple of degrees short at most spots. Even with
that said...Widespread upper 80s along the I-75 corridor...with
middle 80s across eastern Polk/Highlands counties where a slight
cooling influence of the Atlantic waters will be felt due to the
easterly flow.
&&
.LONG TERM (Wednesday through next Monday)...
On Tuesday night a strong ridge aloft positioned over Florida
with a surface ridge extending along south along the eastern
seaboard and over Florida with dry air over north and central
Florida. The upper ridge slowly migrates westward through early
Thursday keeping temperatures 5 degrees above normal as a short
wave and cold front travels eastward across the northern tier of
states. The upper high retreats over TX and the shortwave
amplifies southward along the eastern U.S. coast as the cold front
approaches and moves south through Florida on Friday. The cold
front brings slightly increased chances for precipitation Friday.
After the cold front passes, an area of cool and dry high pressure
settles over the southeast and provides a moderate to strong
easterly wind flow across the peninsula. Temperatures over the
weekend will cool into the 50s for lows and 70s for highs.
&&
.AVIATION (31/18Z - 01/18Z)...
VFR conditions prevail through the period for all terminals.
Light to moderate northeast winds in place across the region.
Winds will diminish and become less gusty as we approach sunset
this evening. Patchy/Areas of fog (locally dense) should re-
develop once again after midnight, but is currently anticipated to
generally remain north of the I-4 corridor terminals.
&&
.MARINE...
Easterly flow will dominate the marine forecast the next several
days as high pressure remains to the north of the region. The
position of the ridge to our north will support enhanced surges of
easterly flow developing during the evening hours. There is a high
potential for winds to reach cautionary levels at many spots by
later this evening into the overnight hours...and then again
Tuesday night. This general pattern should be expected to continue
through Wednesday night before our next cold front approaches from
the north Thursday night into Friday.
&&
.FIRE WEATHER...
High pressure will remain to the north of the region through the
middle of the week...keeping a large scale east to northeast flow
ongoing. Although conditions will be generally dry with seasonably
warm temperatures...relative humidity values are not anticipated
to drop below 35 percent. Dispersion indices will be elevated
through Wednesday.
Fog Potential...Areas of fog are possible late tonight...mainly
to the north of the I-4 corridor. A few locations are likely to
see dense fog...although widespread dense fog...similar to what
was seen on Monday morning is not expected.
&&
.Preliminary Point Temps/PoPs...
TPA 66 86 69 85 / 0 0 0 20
FMY 66 86 67 86 / 0 0 0 10
GIF 64 86 66 84 / 0 0 10 20
SRQ 65 83 67 85 / 0 0 10 10
BKV 61 87 63 85 / 0 0 10 20
SPG 68 85 70 84 / 0 0 0 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...None.
Gulf waters...None.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WEATHER...Mroczka
LONG TERM/DECISION SUPPORT...Paxton