Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 11/17/20
Area Forecast Discussion
National Weather Service Gaylord MI
941 PM EST Mon Nov 16 2020
.UPDATE...
Issued at 940 PM EST Mon Nov 16 2020
Synoptic light snow has been falling this evening over far
southern parts of the forecast area (MBL/CAD/Gladwin). This is
associated with a well-defined shortwave moving ese-ward into the
central Great Lakes. The rest of northern lower MI is relatively
quiet, though with a Superior-Huron lake effect band edging closer
to Cheboygan and Rogers. More vigorous (but transitory) lake
effect is occurring in eastern upper MI. Bands are being displaced
southward with time as 1000-850mb winds gradually veer from wnw
to nw. Sault Canada vsby was down to 1 1/4SM earlier in a
graupelly snow.
The re-establishment of a Superior connection thanks to veering
winds will reinvigorate snow showers in northern lower MI, toward
and after midnight. That said, for earlier parts of the night
pops have already been sharply lowered. There is vigorous enough
activity in eastern upper MI to support a general 1-3" in Chippewa
Co. The real question is where and when any dominant bands can get
established, once the fetch settles down. And the primary signal
from the models is that this will take until somewhat late in the
overnight. Eventually, in northern lower, a stronger band will
likely set up from Bellaire to HTL (as expected by the day shift),
but that will take until well past midnight. Similarly, a
dominant band off of Superior (with a Lk Nipigon origin, a common
sight early in the season) should favor something along or just
east of a Paradise- Cedarville-Rogers City band.
Have made adjustments to pops/QPF into Tue morning, in particular
increasing snow amounts near that Paradise-Cedarville-Rogers
axis. The HRRR spitting out of 0.70" QPF in central Chippewa Co by
mid afternoon Tue is probably overdone, but does raise eyebrows
here anyways. Have 2-5" over 18hrs (overnight-Tue afternoon) from
western Chip to eastern Mack, eastern Presque Isle, and far ne
Alpena Cos. I`m not issuing an advisory at this time, but
seriously considered doing so. Confidence level isn`t quite there,
yet. Will make some changes to the HWO shortly, and of course this
and later shifts will be watching trends closely.
The day shift already targeted a small area of Antrim/Kalkaska Cos
for 2-5" overnight and Tue, that still looks reasonable.
&&
.NEAR TERM...(Through Tuesday)
Issued at 241 PM EST Mon Nov 16 2020
...Lake Effect Snow for Some Tonight into Tuesday...
High Impact Weather Potential...Possible slick roads and reduced
visibility across the snowbelts.
Pattern Synopsis/Forecast...Northwest flow aloft will continue to
transport cold air into the region tonight into Tuesday. Surface
high pressure will then begin to build in Tuesday afternoon.
Primary Forecast Concerns...Extent and intensity of lake effect
snow.
A short wave currently moving across Wisconsin will increase
moisture and over lake instability across northern Michigan
overnight into Tuesday morning. The flow will veer from westerly
this afternoon into the northwest later this evening and continue
into Tuesday. Therefore, am expecting northwest flow lake effect
snow showers to be on the increase tonight then continue into
Tuesday morning (may be a little mixy near the shorelines). Surface
high pressure and associated drier air should then begin to diminish
activity Tuesday afternoon and evening. There is plenty of over lake
instability with lake/850 mb delta ts in the lower 20s. However,
moisture is just okay with 850-700 mb rh on the order of 60 to 70
percent. Looking at model soundings...more of the same with
inversion heights only expanding to a modest 4000 to 5000 feet or
so. The flow should tap both Lake Superior and Lake Michigan and
with the excellent over lake instability there could be a couple of
decent bands that form...one across eastern upper and another one
off of Lake Michigan targeting the Kalkaska and Houghton Lake areas.
Won`t go too crazy with accumulations for now due to uncertainty
over how things set up with upwards of a couple of inches in these
areas. However the overnight shift should monitor current trends and
an advisory though unlikely isn`t out of the question. Meanwhile,
plenty of clouds across much of northern Michigan should limit
diurnal and nighttime temperature ranges so increased lows into the
mid 20s to low 30s and lowered highs into the upper 20s to mid 30s.
Northwest winds will pick some with gusts pushing 25 to 30 mph
overnight into Tuesday morning. These winds will make it feel rather
brisk with apparent temperatures only ranging from the mid teens to
low 20s Tuesday...burr!
&&
.SHORT TERM...(Tuesday night through Thursday)
Issued at 241 PM EST Mon Nov 16 2020
High impact weather potential: Some chances for lake effect snow,
only light accumulations expected at this time.
Pattern synopsis and forecast:
Northwesterly flow will continue as the forecast area remains wedged
between high pressure centered off to our southwest and a low
pressure system east of the Hudson Bay. There is still available
moisture, delta t/s reaching nearly 20C, and inversion
heights of around 4-5kft...expect lake effect snow Tuesday night
through Wednesday morning. I do not expect too much accumulation of
the snow to occur...only minor accumulations. Said high pressure to
our southwest will be building into the forecast area...providing
drier low-levels and flow will become more anticyclonic. Only
forecasting about 1-2" as the highest snow totals by Wednesday
morning. High pressure will continue to build over the Great Lakes
region Wednesday...decreasing cloudiness and ending precipitation
chances. Skies will be partly to mostly cloudy Wednesday afternoon
and beyond. A very weak and moisture starved cold front will
approach the forecast area during the day Thursday...increasing
cloudiness, but no precipitation is forecast at this time.
Winds will begin to back to the southwest through Wednesday morning
and decreasing in intensity as the pressure gradient relaxes and
high pressure builds in. As the high pressure moves to the east the
winds will become gusty once again as the forecast area is once again
wedged between a low pressure system off to the northwest an the
aforementioned high pressure off to our southeast...tightening the
pressure gradients once again and producing wind gusts of around 20
mph by the late afternoon/evening hours. Winds will continue to be
gusty and out of the southwest throughout the remainder of this
forecast period.
Daytime temperatures will be in the upper 30s to low 40s Wednesday
with the WAA on southwesterly winds and warm into the low 50s
Thursday. Overnight lows Tuesday night will generally be in the 20s,
with some of our "cold spots" reaching into the teens. Wednesday
night will only drop into the upper 20s to low 30s.
.LONG TERM...(Thursday night through Monday)
Issued at 241 PM EST Mon Nov 16 2020
High impact weather potential: None
High pressure will continue to dominate northern Michigan`s weather,
with precipitation-free weather and partly to mostly cloudy skies
throughout much of the day Friday. The long term models are hinting
at the next storm system developing on the lee side of the Rockies
and beginning to impact the Great Lakes region by Friday night and
continuing to do so through the rest of the forecast period with
synoptic precipitation falling as either a rain/snow mix or all
snow. There is an area of high pressure and dry air just north of
the northern edge of this system...which could make a defining line
of where precipitation is and isn`t. This will be something to watch
for in the future model runs. As of right now the line is running
through the Straits area, but could waver north or south in future
runs. Winds could be gusty at times...especially during the
afternoon hours with diurnal mixing, but no major wind system
noticed at this time. Temperatures will remain a bit above
normal. Nighttime temperatures will generally be in the 30s, with
warmer temperatures near the shorelines of the Great Lakes.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 623 PM EST Mon Nov 16 2020
An upper level disturbance is bringing -SN to parts of central and
southern lower MI. MBL will see IFR conditions in -SN for another
2-3 hours. Lake effect snow should increase in coverage/intensity
after this departs, as somewhat cooler air moves in. That will
make MVFR cigs more prevalent, and chances for snow showers
tonight into Tue.
Current westerly breezes will veer nw, and become a little gustier
overnight and Tuesday.
&&
.MARINE...
Issued at 241 PM EST Mon Nov 16 2020
Small craft advisory wind speeds are expected through at least
Tuesday and across some spots into the first half of Tuesday night.
In addition, a few gusts to near gale force are possible later
tonight into Tuesday morning. High pressure and lighter winds arrive
overnight Tuesday into Wednesday morning. Return flow gusty
southerly flow then looks to ramp up Wednesday afternoon. Mainly
light lake effect showers are expected through Tuesday evening in
the typical snowbelts.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY until 6 PM EST Tuesday for LHZ345>348.
SMALL CRAFT ADVISORY until 11 PM EST Tuesday for LHZ349.
LM...SMALL CRAFT ADVISORY until 6 PM EST Tuesday for LMZ323-341-342-
344>346.
LS...SMALL CRAFT ADVISORY until 6 PM EST Tuesday for LSZ321-322.
&&
$$
UPDATE...JZ
NEAR TERM...AS
SHORT TERM...TL
LONG TERM...TL
AVIATION...JZ
MARINE...AS
Area Forecast Discussion
National Weather Service State College PA
1053 PM EST Mon Nov 16 2020
.SYNOPSIS...
A seasonably cold and brisk weather pattern is expected into
midweek with below average temperatures, gusty winds, and lake
effect snow showers. A general 1 to 3 inches of snow is probable
in the northwest PA snowbelts and higher elevations of western
PA late tonight through Tuesday. The early to midweek chill will
be short-lived with temperatures trending warmer to above
average from Thursday through the upcoming weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Clouds will overspread the region tonight, as clipper approaches
from the lower Grt Lks. Upstream radar imagery at 03Z shows
an area of light rain and snow across lower Michigan/northwest
Ohio in region of waa ahead of clipper. RAP 850-700mb fgen
forcing fields suggest this area of light precipitation will
spread across the northern part of the forecast area between
06Z-11Z. Although model soundings indicate it will be cold
enough for snow, a blend of latest guidance indicates any
accumulations across the northern counties will be less than an
inch.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
Weak, moisture-starved clipper is progged to exit the region
around or shortly after 12Z Tuesday, followed by a seasonably
cold northwest flow, which will support a period of lake effect
snow showers across primarily the northwest mountains/Laurel
Highlands Tuesday into Tuesday night.
The most widespread lake-enhanced orographic snow showers are
expected during the morning hours. Falling inversion heights
expected with passage of upper trough axis during the afternoon
is likely to result in diminishing snow shower coverage at that
time. However, models indicate some locally heavy snow
showers/squalls are possible during the afternoon across the
Allegheny Plateau, where models indicate steep lower
tropospheric lapse rates and some minimal surface-based cape.
While inversion heights between 800-750mb are not conducive for
heavy snow rates, convection allowing models are signaling the
possibility of a fairly significant single band with Lk Huron
connection affecting parts of Warren County late Tuesday
afternoon or early evening. Expect dwindling snow showers later
Tuesday night, as high pressure approaches and inversion
heights fall.
A blend of NBM/WPC/HREF guidance support a general 1-3 inches
Tuesday/Tuesday evening over the NW mtns, with up to 4 inches
possible across the snowbelt of northwest Warren Co. Elsewhere,
expect a coating to an inch or two along the Laurel Highlands.
Parts of the south-central Alleghenies eastward into the
ridge/valley region will see periods of rain/snow showers but no
accumulation forecast south/east of I-99/US-220.
Coordination with neighboring offices lead to no advisory
issuance with this shift given lack of advy level accum in
any 12hr period. Will continue to message potential travel
disruptions in the HWO and social media platforms. Cold
cyclonic flow pattern is often a good opportunity to trend
daytime highs below guidance.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Wednesday should feature fair and chilly conditions, as surface
high builds over the state. Latest ECENS and GEFS continue to
support fair and progressively milder weather late week into
next weekend, as upper trough lifts out and is replaced by a
broad ridge over the eastern CONUS. Ensemble plumes indicate
well above normal temperatures are likely late week into the
weekend, as surface high slips off the Mid Atlantic coast and
southwesterly return flow develops.
A dying cold front appears likely to approach from the north by
Saturday, but have kept most of the area dry per latest NBM
POPs and based on lack of significant forcing. A better chance
of showers will likely come with the arrival of a more potent
cold front by Monday of next week.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
00Z TAFS sent. Winds still up in some spots, but should die
off by 02Z. Skies clear across the region now.
A fast moving weak low near the western Great Lakes will bring
some patchy light rain and snow to the area late tonight and
early Tuesday.
This will be followed by a deep northwest flow of air off
the Great Lakes Tuesday afternoon with snow showers across
the west, along with gusty winds. Thus BFD and JST will see
poor conditions for aviation on and off throughout the day.
Improving conditions by Wednesday afternoon, as winds
weaken and warming aloft shuts down the lake effect snow
showers.
The rest of the week will feature a major warm up and a
return to mainly clear skies.
Outlook...
Wed...Low cigs psbl early wrn 1/3. Bcmg VFR with winds
subsiding.
Thu...VFR/no sig wx. Southerly breeze developing.
Fri...VFR/no sig wx.
Sat...Rain possible along frontal zone over the NW airspace.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Steinbugl
NEAR TERM...Fitzgerald
SHORT TERM...Fitzgerald/Steinbugl
LONG TERM...Fitzgerald/Travis
AVIATION...Martin
Area Forecast Discussion
National Weather Service Dodge City KS
455 PM CST Mon Nov 16 2020
...Updated aviation section...
.SHORT TERM...(This evening through Tuesday)
Issued at 1222 PM CST Mon Nov 16 2020
Morning water vapor satellite imagery and RAP analysis depicts a
longwave upper ridge building over the western CONUS with a
longwave trough downstream over the eastern CONUS. These features
will move slowly eastward today as surface high pressure builds
into the high plains. Surface winds are in the process of veering
from northerly to southerly in response to building high pressure,
and this has also caused southwest Kansas to lose the downslope
component to the winds. Consequently, most areas have likely
achieved, or are near their high temperature for the day.
Temperatures should hold in the 60s during the day before dropping
into the lower 30s overnight.
The upper level pattern will begin to dampen Tuesday as another
longwave trough approaches the west coast. A lee cyclone will
develop and deepen in eastern Colorado making Tuesday much windier
with sustained south winds in the 20-25 mph range and gusts up to 35
mph possible. Highs will be warmer given the south winds and most
areas should see upper 60s to low 70s.
.LONG TERM...(Tuesday night through Monday)
Issued at 208 PM CST Mon Nov 16 2020
At the beginning of the long term period, an upper level ridge
will be centered over the central plains with a trough moving
inland over the west coast states. A deep surface cyclone will be
located over southern Alberta with an associated pressure
influence extending into the southern plains. South winds will
only weaken slightly Tuesday night limiting overnight radiational
cooling and keeping most of southwest Kansas in the low to mid
40s. South winds will increase once again Wednesday as the surface
cyclone traverses southern Canada and slowly fills. Wednesday
will be the warmest of the period, with highs ranging from the mid
70s in central Kansas to the low 80s near the CO/KS border. Winds
will finally begin to relax Wednesday night as the tightest
surface pressure gradient slides to our east.
Thursday will likely see a weak cold front associated with the low
in Canada sag into southwest Kansas during the day as the upper
level pattern dampens to near zonal flow. This boundary will
stall out somewhere across our area, however guidance differs on
exact placement. Highs Thursday south of this boundary will reach
into the low 80s, while areas north of the boundary will likely
stay in the upper 60s to low 70s. Friday will be cooler owing to
increased cloud cover and the cold front beginning to move south.
Overnight Friday into Saturday morning, guidance suggests a series
of impulses will eject into the central plains pushing the cold
front through the rest of the area. Guidance is in decent
agreement that rain will develop Saturday behind the front and
last through at least Sunday evening, possibly lingering into
Monday morning in our southeast zones. Periods of wintry mix or
snow is also possible, especially in our northwest zones, Sunday
and Monday morning, however no accumulation is expected. Another
warming trend should begin Monday as south winds resume on the
west side of surface high pressure.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 454 PM CST Mon Nov 16 2020
VFR conditions will prevail through tomorrow with mostly clear
skies. Winds will shift to a southerly direction by sunrise
tomorrow and increase in speed by tomorrow afternoon. Gusts above
25 knots are expected at this time.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 35 67 45 75 / 0 0 0 0
GCK 32 68 41 76 / 0 0 0 0
EHA 33 71 43 80 / 0 0 0 0
LBL 31 70 42 78 / 0 0 0 0
HYS 33 67 43 74 / 0 0 0 0
P28 36 66 42 72 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Springer
LONG TERM...Springer
AVIATION...Hovorka_42
Area Forecast Discussion
National Weather Service Goodland KS
444 PM MST Mon Nov 16 2020
.SHORT TERM...(This evening through Tuesday)
Issued at 1253 PM MST Mon Nov 16 2020
19Z Water vapor imagery and RAP analysis indicated CWA in broad
northwesterly flow aloft with large H5 ridge to the west of the
area, centered over the northern Rockies. At the sfc, 1027 mb high
was centered over west central Nebraska south into the Goodland
area.
Weather across the Tri State area will be quiet through the period
as aforementioned H5 ridge amplifies and moves over the region.
This will lead to widespread subsidence and dry conditions through
the period. Temperatures will continue to warm and based on how
fast todays temperatures reached or exceeded the expected values
today, think the warmer solutions pushing into the lower 70s looks
reasonable. Strong lee trough will develop Tuesday morning leading
to increased southerly winds into the afternoon. May see a few
locations near a Tribune to Oakley line where sustained winds
approach 30 mph. Right now, humidity values are not expected to be
low enough to warrant any fire highlights.
.LONG TERM...(Wednesday through Monday)
Issued at 1221 PM MST Mon Nov 16 2020
The main points of interest for the extended period include above
normal temperatures and elevated fire weather conditions on
Wednesday, plus rain chances towards the end of the week and through
the weekend.
The early week ridge pushes off to the east as zonal flow overtakes
the area for Wednesday and Thursday. Wednesday will feature warm,
above normal temperatures with near record to record breaking
temperatures looking more likely. Elevated to near critical fire
weather still looks possible as RH values fall to the mid teens
during the afternoon. The only question if criteria may be met is
the winds. Southerly sustained winds of 10-15 knots are expected
during the morning but diminishing as the afternoon goes on,
afternoon mixing may allow some gusts of 20-25 knots but those may
be spotty. As of right now its appearing the best area of
potentially meeting criteria is located south of I70 and west of
Highway 27. Thursday won`t be nearly as warm but still above normal
as a cold front moves across the Tri-State area during the afternoon
hours.
Friday and throughout the weekend, the pattern begins to change as
southwesterly flow in advance of a trough advance towards the area.
Moisture advection from the Gulf of Mexico makes its way into the
plains during the day Friday. As the disturbance gets closer during
the night on Friday enough lift is expected to produce rain showers
that will last until early Sunday morning. PWAT values ranging from
the 97.5-99th climatological percentile indicated that a nice,
needed soaking rain is appearing possible at this time. Currently,
it appears an all liquid event is most likely but some snow may try
to mix in as well, especially during the overnight hours as
temperatures cool. A last final shot of precip is possible during
the night on Sunday as any additional rain showers may switch over
to snow as low temperatures drop into the 20`s and 30`s.
Widespread 70`s and isolated 80`s are in store for Wednesday. A cold
front moving through the area on Thursday will cap the
temperatures at the mid 60`s in the northwestern portion of the
CWA while the remainder will be in the 70`s. As colder air moves
back into the area highs on Friday will mainly be in the 50`s
before widespread 40`s will encompass the entire area for the
weekend.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 418 PM MST Mon Nov 16 2020
VFR conditions are expected at MCK and GLD through the 00Z TAF
period. Mostly clear skies are expected with light south winds
overnight becoming gusty out of the southwest during the afternoon
on Tuesday.
&&
.CLIMATE...
Issued at 510 AM MST Mon Nov 16 2020
Record/near record high temperatures are expected Wednesday
November 18 at the following locations:
Goodland..........77 degrees set in 2008 and previous years
McCook............76 degrees set in 1933
Burlington........76 degrees set in 2008
Colby.............76 degrees set in 1981
Tribune...........78 degrees set in 1999
Yuma..............76 degrees set in 1999
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...JRM
LONG TERM...TT
AVIATION...LOCKHART
CLIMATE...DDT
Area Forecast Discussion...CORRECTED
National Weather Service Miami FL
706 PM EST Mon Nov 16 2020
.Aviation...
Moisture will increase across the region overnight and tomorrow
as a cold front approaches the area from the north. Conditions
should gradually deteriorate with VCSH/SHRA increasing over the
adjacent Atlantic waters. While a few of these may spill over the
east coast terminals, primarily VFR conditions should prevail.
Additionally, ENE winds will also gradually increase and veer out
of the NE in the fronts wake.
&&
.Update...
Latest surface analysis drapes a frontal boundary just north of Lake
Okeechobee. Along the boundary and across the southern edge of the
peninsula, satellite derived PWATs reveal enhanced swaths of
moisture which are helping to spark some shallow convection this
evening. As the front approaches overnight and into tomorrow,
coastal convergence could allow for an uptick in coverage of showers
and perhaps a few thunderstorms, mainly along the east coast and
adjacent Atlantic waters. Gusty northeasterly winds in the
boundary`s wake will allow for seas to become agitated, first in the
Gulf and later in the Atlantic. Therefore, have hoisted a Small
Craft Advisory for the Gulf waters beginning at 7 AM EST. Advisories
for the Atlantic are sure to follow in forthcoming updates.
&&
.Prev Discussion... /issued 235 PM EST Mon Nov 16 2020/
SHORT TERM...
Today
Mostly dry and cooler today, as a frontal boundary approaches South
Florida. The presence of a long, distinct frontal boundary draped
across central Florida has allowed for a cooler and drier airmass to
begin ushering into the region. This frontal boundary is forecast to
progress southward, which will further allow for a modified
continental polar airmass to advect over the region in the coming
days. A large subsidence inversion is evident on the 12Z MFL
sounding, indicative of synoptic scale subsidence, likely owing to
the presence of a short-wave ridge advecting over the area. This
should quell shower and storm activity, as the best chances for
precipitation today will be confined to northern portions of the
forecast area. The warming with height in the mid/upper levels
indicates that any convective development will be hampered by a
hostile synoptic-scale environment today, and any activity that does
develop is forecast to be relatively short-lived.
Tuesday
The aforementioned cold-front is forecast to progress
south/southeastward, approaching South Florida early morning
Tuesday. Ahead of this boundary, a wedge of higher theta-e air
exists within the boundary layer, particularly over the nearshore
Atlantic waters and continuing over the Atlantic metro region. RAP
guidance shows a coastal moisture convergence setup ahead of the
front, with the strongest signal presently located over the Palm
Beach/Broward County border. Regardless, showers are possible for
the entire Atlantic metro region. The main concern is localized
flooding, particularly in poorly-drained urban regions. Isolated
thunderstorms are also possible, but instability will be lackluster
owing to cooler near-surface temperature advection likely which will
act to reduce thunderstorm potential/potency.
Maximum temperatures will transition from seasonable today
(mid/upper 80s) to seasonably cool Tuesday (low/mid 80s) with the
cold-front providing modest relief across the region.
LONG TERM...
Tuesday Night through Friday...
A mid-level ridge will gradually progress from the southern Great
Plains towards the eastern Gulf of Mexico by Friday. This will
support a strong surface high pressure area while it slides
southeast from the Ohio Valley towards the South Atlantic states. A
cold front initially across far southern portions of the area may
bring showers to southern/eastern Miami-Dade County during the
evening hours before drier conditions prevail. As the remnant
front stalls over the northern Caribbean Sea a robust pressure
gradient will prevail. Given northeast 925 mb winds averaging
25-30+ kt and the potential for downward momentum transport into
the surface layer, a Wind Advisory may be needed for the eastern
coastal areas. Otherwise the biggest sensible weather change will
be lower humidity values and a slight decrease in temperatures.
The coolest period should be Wednesday into Thursday, with highs
mostly in the 70s and lows mostly in the 60s away from the
Atlantic coast. However the onshore wind component should keep
readings in the 70s along the eastern coastal interface. A few
showers may approach from the east by Friday evening.
Saturday through Monday...
The upper ridge across our area is forecast to weaken as a closed
upper circulation develops over the Bahamas. This feature, and an
associated surface low, are forecast to pinwheel in place over the
weekend before ejecting to the north/northeast next week ahead of an
approaching trough. While South Florida should remain displaced from
the deeper moisture associated with this system, enhanced cloud
cover and shower chances may return. Breezy conditions will
continue. Temperatures should remain seasonal, with highs mostly in
the 80s and lows in the upper 60s to mid 70s.
MARINE...
Though Monday appears to be a relatively benign marine weather day,
this will change Tuesday as a cold-front approaches the region. The
front and corresponding tightening pressure gradient force will act
to increase wind speeds across the local waters, and isolated gale
force gusts are possible as early as Tuesday afternoon/evening. This
will likely warrant a Small Craft Advisory, as there is increasing
confidence that the winds will meet this criteria, particularly for
the Atlantic waters. With the tightening pressure gradient expected
to continue through the week, a prolonged SCA may be necessary.
BEACHES...
Isolated showers are possible today, particularly over Palm Beach
County. Rip current risk remains low for Monday, however this will
change for the Atlantic on Tuesday and especially going into mid-
week with an approaching cold front. The cold front and
corresponding higher wind speeds are also forecast to increase the
surf heights across the waters, especially over Palm Beach County.
Finally, New Moon King Tides will continue through midweek. The
continuation of the coastal flood statement is needed through at
least Tuesday as minor coastal flooding during high tides will
remain possible for the Atlantic coast.
PRELIMINARY POINT TEMPS/POPS...
Miami 73 83 70 79 / 30 50 10 0
West Kendall 72 83 69 79 / 20 50 10 0
Opa-Locka 72 82 69 78 / 40 50 10 0
Homestead 72 83 70 79 / 20 50 10 0
Fort Lauderdale 74 83 70 79 / 40 50 10 0
N Ft Lauderdale 73 81 70 77 / 40 50 10 0
Pembroke Pines 73 83 70 80 / 40 50 10 0
West Palm Beach 72 80 69 77 / 40 50 0 10
Boca Raton 73 82 70 79 / 40 50 0 10
Naples 69 82 62 80 / 10 0 0 0
MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
GM...None.
$$
Tonight/Tuesday and Aviation/Marine...Bhatti
Tuesday Night through Monday...SPM
Visit us at weather.gov/miami
Follow us on Facebook and Twitter at:
www.facebook.com/nwsmiami
&&
.Preliminary Point Temps/PoPs...
West Palm Beach 72 80 69 77 / 40 30 0 10
Fort Lauderdale 74 82 70 79 / 30 40 10 0
Miami 73 82 70 79 / 30 40 10 0
Naples 69 82 63 80 / 10 0 0 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
GM...Small Craft Advisory from 7 AM Tuesday to 7 PM EST Friday for
CMOS-657-676.
&&
Aviation/Update...11/HVN
Area Forecast Discussion
National Weather Service Pocatello ID
158 PM MST Mon Nov 16 2020
.SHORT TERM...Tonight through Wednesday night.
Will have dry and warm conditions through Tuesday ahead of the
next Pacific storm system. This system will quickly move moisture
into central and southeast Idaho Tuesday night with rain and snow
overspreading the area. Snow levels will be high, generally
between 6 and 7 thousand feet but high elevations could see heavy
snow. A winter storm watch has been issued for the central
mountains where some mountain passes...especially Galena Summit
could see a foot of snow. The watch is in effect from 11 pm
Tuesday night until 11 PM Wednesday night. Expect mainly rain in
the valleys. High temperatures will be well above normal through
Wednesday with highs in the 50s in the valleys Tuesday with some
slight cooling in cloud cover and precipitation into the 40s
Wednesday. Winds are not expected to be too strong with this
system with limited drifting at the high elevations.
GK
.LONG TERM...THURSDAY THROUGH NEXT MONDAY...
Our wx for the end of the week and upcoming weekend is looking
fairly low-impact at this juncture in the wake of our mid-week storm
system. Snow showers may linger Thurs in most of our mtn ranges
with generally an additional 2 inches or less of accumulation,
with a drying trend ensuing Fri, Sat, and Sun as a shortwave high
pressure ridge rides through the active storm track. Agreement
between the GFS, ECMWF, and Canadian seems to be increasing in
this scenario. NBM guidance still seems a little overdone on PoPs
and cloud cover under this ridge, but we expect this should trend
in line over the next couple days if agreement among the input
models holds. By Sun night/Mon AM, yet another shortwave trough
moves inland across the nrn Rockies, although models disagree on
how much rain/snow shower activity this feature will be able to
generate across SE Idaho (near the srn fringes of the shortwave),
so confidence remains very low beyond Sun. Temps should remain
fairly stagnant throughout the period, topping out in the 30s most
afternoons for most locations, which is near to just a couple
degrees below normal for mid-Nov. Sat/Sun AMs may be quite cold
(single digits to teens) depending on clearing. - KSmith
&&
.AVIATION...
Early afternoon satellite shows continued erosion/NE progression of
a mid-level cloud deck at about 8,000 feet, allowing KPIH/KBYI to
break out into sunshine and finally allowing us to get a visual on
low stratus socked in from some of the Central Mtn valleys east
across the Upper Snake Plain, Upper Snake Highlands, and Teton
Valley regions. This is affecting KIDA in particular where IFR
vsbys continue. Pretty much all guidance progressively burns off
this low stratus over the next several hours, but this may be just
a bit too progressive per satellite trends. For now we continue
to break KIDA out to VFR cigs around 21z and will amend to push
that out if needed...KRXE is leaning this direction already so
that`s a good sign. Behind the stratus, non-impactful wx should
take hold in the form of a large swath of sct high-level clouds
advancing in across OR/wrn ID and pretty light sfc winds as weak
high pressure builds in. We continue to watch for potential
development of southerly winds downsloping off the mntns south of
KPIH this afternoon/eve per HRRR guidance which may allow a runway
crosswind and gusts over 20kts. The other big element we need to
watch closely is LLWS potential by daybreak Tue AM at all
terminals (except perhaps KSUN) as 1,500-2,000 ft winds may exceed
35kts out of the SSW and sfc mixing seems unlikely due to VERY
strong inversions advertised on NAM/RAP forecast soundings (this
lack of mixing is particularly evident on MOS guidance, and COULD
even hold into the afternoon). We have not included LLWS in the
TAFs yet, but inclusion is looking increasingly likely in future
updates. The increase in winds aloft is ahead of our next wx
system that will bring rain/snow showers and lowering cigs
regionwide by Tue night/Wed AM. - KSmith
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
Winter Storm Watch from Tuesday evening through Wednesday
evening for IDZ072-073.
&&
$$
Area Forecast Discussion
National Weather Service Reno NV
222 PM PST Mon Nov 16 2020
.SYNOPSIS...
A storm moves in Tuesday for strong winds, especially in eastern
California and far western Nevada. Some wind damage is possible
in the immediate lee of the Sierra. Rain and higher elevation snow
are likely later Tuesday and Wednesday with travel in the Sierra
affected. Mild temperatures through Tuesday will fall closer to
average mid-week through the weekend.
&&
.SHORT TERM...
Forecast thinking now supports a bit stronger winds Tuesday with a
solid high wind event now expected for eastern CA and far western
NV. As far as snowfall amounts for the Sierra from Alpine County
northward and above valley floors across northeast CA, a good number
of simulations have increased their QPF with snow levels possibly a
bit lower than previously expected. In any case, there is high
confidence that travel over Sierra passes and the higher roads across
northeast CA will be affected by snow Tuesday night and Wednesday.
Let`s break the weather elements down...
* WIND...
Wind projections for Tuesday from blended model guidance have
come up a bit more this morning. Also, now that short-term
guidance from the HRRR is available to add confidence, concern
has increased for a solid high wind event (more widespread peak
gusts to 60+ mph) for eastern CA and far western and northwestern
NV. More damage is possible than with the last round of wind (last
Friday) as fencing/trees could have been weakened from those
winds and this event could feature a good 8-12 hours of strong
wind ahead of the cold front. See our wind statements for more
details of the expected wind speeds and impacts.
Farther east into the west-central NV basin and range, given
that good mixing is expected with 700 mb winds 40-55 kts ahead
of a cold front, we now expect wind gusts to peak out in the
40-55 mph range Tuesday afternoon-evening. Thusly, a wind
advisory has been issued for Pyramid Lake and Pershing and
Churchill counties.
Blustery conditions with gusts to ~25-40 mph are expected Wednesday
as the region remains under the influence of troughing with winds
aloft remaining elevated.
* PRECIPITATION...
Many simulations have come in with heavier precipitation totals
Tuesday-Wednesday, especially in eastern California from Alpine
County northward but also possibly out into portions of western and
northwestern NV. Models now show a secondary wave moving over northern
California Wednesday morning which, with the moist westerly flow on
the unstable side of the cold front (hung up in Alpine County
and out into the Basin and Range), should result in another push
of rain and higher elevation snow. This feature, along with the
main period of heavier precipitation Tuesday night, have pushed
confidence in higher QPF upwards with a winter storm warning to be
issued for Lake Tahoe. Also, a bit colder air may filter into
northeast CA and northwest NV than expected previously due to the
more defined secondary wave. This may allow for more snowfall down
to between 5500-6000 feet (affecting Truckee and the Lake Tahoe
Basin) than was previously expected through Wednesday. See the
latest winter statements to be issued this afternoon for more
details.
With heavier precipitation still appearing to hang up in Alpine County
as the upper jet and cold front stall in their southward propagation,
precipitation totals for Mono County remain rather unimpressive with
the bulk limited to west of Highway 395. Still, there should still be
some relief for drier timber.
-Snyder
.LONG TERM...Thursday onward...
A weak trough over the western U.S. Thursday will maintain cool
temperatures, with mostly cloudy skies and chances for light showers.
Snow levels within these showers could come down to below 5,000
feet, but any snow accumulations are expected to be localized and
fairly light. Clouds should be on the decrease by Thursday night
as the trough exits to the east and then a weak high-pressure
ridge builds Friday though the weekend. With this ridging,
overnight inversions will return leading to cold morning
temperatures in valleys (single digits in the typically colder
spots) and as a result afternoon temperatures may warm only a
degree or two.
For next week, the pattern continues to be progressive but there are
some indications the weather systems could be weaker compared to
tomorrow`s storm and that the deeper moisture may stream more into
the Pacific Northwest. That said, there is still potential for snow
(especially at mountain passes) which could impact Thanksgiving
holiday travel. Make sure to stay tuned to the forecast if you have
travel plans next week. JCM
&&
.AVIATION...
After fairly light surface winds through this evening (southeast-
south around 10 kts) winds increase overnight tonight and become
very strong tomorrow as a strong jet aloft move over the Sierra
and western Great Basin.
* WINDS: Winds aloft will increase significantly 06-12Z Tuesday
with ridge level winds 40-55 kts, gusts to 70+ kts. These winds
get even stronger Tuesday after 12z with ridge level winds 50-70
kts with gusts up to 100+ kts. South-southwest winds will
develop at the Tahoe terminals early Tuesday morning and then
expand to all of the eastern Sierra and western NV, intensifying
during the morning and afternoon Tuesday. Moderate to severe
turbulence, LLWS and rotors will be common with widespread
surface wind gusts 40-55 kts, locally stronger to 60-70 kts in
wind prone areas along the Highway 395 corridor from Susanville
to Lee Vining. Surface winds will back off in these areas
Tuesday night as precipitation arrives, but turbulence will
likely continue Tuesday night and Wednesday as winds aloft
remain strong. Surface winds will likely stay strong from Lee
Vining south into KMMH well into the night Tuesday night (gusts
45+ kts at KMMH).
* RAIN/SNOW: Rain and high elevation snow will bring mountain
obscurement to the Tahoe Basin northward into Lassen County
beginning Tuesday evening and continuing overnight and Wednesday
morning. Snow levels will start above area terminals but there
is a chance for rain to change to snow at KTRK and KTVL with up
to 3 inches of wet snow possible. Precipitation and terrain
obscuration will spread into western NV Tuesday evening and
Tuesday night, but fewer impacts are expected for locations east
of Highway 95. JCM
&&
.REV Watches/Warnings/Advisories...
NV...Wind Advisory from 10 AM Tuesday to 4 AM PST Wednesday NVZ001.
Winter Storm Warning from 4 PM Tuesday to 6 PM PST Wednesday
NVZ002.
High Wind Warning from 9 AM to 7 PM PST Tuesday NVZ005.
High Wind Warning from 7 AM to 4 PM PST Tuesday NVZ002.
High Wind Warning from 10 AM to 7 PM PST Tuesday NVZ003.
Wind Advisory from 10 AM to 10 PM PST Tuesday NVZ004.
CA...Winter Weather Advisory from 1 PM Tuesday to 6 PM PST Wednesday
above 5500 feet in CAZ071.
Winter Storm Warning from 4 PM Tuesday to 6 PM PST Wednesday
CAZ072.
High Wind Warning from 9 AM to 7 PM PST Tuesday CAZ070-071.
High Wind Warning from 10 AM Tuesday to 4 AM PST Wednesday
CAZ073.
High Wind Warning from 7 AM to 4 PM PST Tuesday CAZ072.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno