Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 09/08/19
Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
628 PM CDT Sat Sep 7 2019
.UPDATE...
Issued at 624 PM CDT Sat Sep 7 2019
Some areas along the Missouri are seeing about a 2-3 hour break
in the rain this evening before the next wave comes in from the
west. Attempted to adjust the pops for this trend. All lightning
activity remains outside of this cwa for the moment. Will continue
to monitor for the next few hours across central SD.
&&
.SHORT TERM...(This Evening through Sunday Afternoon)
Issued at 341 PM CDT Sat Sep 7 2019
The threat for severe storms remains probable over the southwest CWA
this evening, mainly between 23-02Z. An area of low pressure is
situated between KPIR and KPHP where partly sunny skies has allowed
temps to warm into the upper 70s to the low 80s. The SPC`s meso
analysis page indicates greater than 1000 J/KG along with 40 knots
of 0-6 KM bulk shear. A few storms have recently developed over
western South Dakota. With upper level support moving into the area,
thunderstorms could become more widespread over the next few hours.
The HRRR has been consistent with showing a strong storm near Eagle
Butte around 22-23Z. This storm tracks southeast, possibly impacting
Pierre. Winds and severe hail appears to be the main threat with
the storms this evening. Light to moderate rainfall can be
expected elsewhere tonight into the morning hours on Sunday.
Showers will gradually diminish from west to east Sunday morning
with dry conditions likely Sunday afternoon. Cloudy skies, along
with cool low level temperatures, highs on Sunday will be well
below average with highs in the 50s and low 60s. These readings
are 15 to 20 degrees below normal for this time of year.
The next storm system will begin impacting the area Sunday night.
While the western CWA should see the brunt of the pcpn, WAA in the
eastern CWA after 0Z could cause pcpn sooner than expected.
.LONG TERM...(Sunday Evening through Saturday)
Issued at 341 PM CDT Sat Sep 7 2019
When the period opens at 7 AM CDT Monday, precipitation should be
working through, at least, the southwestern third of forecast zones.
Models depict this waa-forced wave of showers/storms moving quickly
northeast across the region on Monday. Some of the qpf output
suggests there could be some pockets of excessive heavy rain with
this event (supported by ensemble-based high pwats and spec
humidities being well over 2 standard deviations above normal for
early September). And, with the amount of afternoon sunshine and low
level moisture advection currently anticipated across central South
Dakota on Monday, can`t rule out a couple of strong to severe
thunderstorms developing. Deep layer shear (35 to 40 knots) supports
organized storms will be possible.
Another wave of low pressure moves over the region in sw flow aloft
Tuesday night into Wednesday morning, bringing precipitation chances
mainly across portions of northeast South Dakota/wc MN, before the
larger, more significant lead shortwave moves in by late in the day
Wednesday/Wednesday night, working pretty good precip chances from
southwest to northeast across the CWA. Models seem to be trending a
bit further north/east with the upper circulation`s track on
Thursday right on through Friday, leaving most of this CWA far
enough south, that the TROWAL-forced precip will not be much of a
factor Thursday afternoon or Thursday night. At the moment, Friday
and Saturday look more dry than wet, although breezy/windy west-
northwest winds are probable on Friday.
Low level waa should put temperatures back to near to perhaps a
little above normal for Monday, persisting into Tuesday. Somewhat
cooler conditions look to set up behind the Wednesday/Thursday
system for the end of the week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 624 PM CDT Sat Sep 7 2019
A mix of VFR/MVFR conditions is expected to deteriorate to
MVFR/IFR tonight as lower stratus moves in.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...Wise
SHORT TERM...SD
LONG TERM...Dorn
AVIATION...Wise
Area Forecast Discussion
National Weather Service Cheyenne WY
523 PM MDT Sat Sep 7 2019
.SHORT TERM...(This evening through Monday night)
Issued at 229 PM MDT Sat Sep 7 2019
A cool front will move south across the CWA this evening with an
otherwise quiet night expected. A few showers not out of the
question over far northern parts of the CWA into this evening
though latest HRRR not showing anything. Next upper shortwave will
be approaching the area from the SW Sunday and should bring a
fairly extensive area of showers and tstms across the CWA Sunday
mid-afternoon through Sunday evening. Shear and instabilities not
impressive but could be enough for a few stronger storms with
strong wind gusts the main threat. A short period of better
instability progged over the southern Panhandle early Sunday
evening so that area most likely to see stronger storms with even
a heavy rain threat as well. Convection should clear out late in
the evening with dry weather Monday.
.LONG TERM...(Tuesday through Saturday)
Issued at 229 PM MDT Sat Sep 7 2019
Unsettled conditions expected Tuesday through Thursday as an upper
trough progresses eastward across the region with daily chances for
showers and a few storms. Should dry out beginning Friday and
continuing Saturday with a warmup.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 516 PM MDT Sat Sep 7 2019
Currently VFR persist at all area terminals going into Saturday
evening with gusty winds at Wyoming terminals that should calm
down after 02Z. Scattered cloud cover will continue to stick
around overnight for the northern Nebraska Panhandle, especially
near KCDR where MVFR ceilings are possible by mid morning
Sunday. Widespread showers and thunderstorms can be expected on
Sunday afternoon for KRWL, KLAR, and KCYS moving towards the
Nebraska Panhandle terminals after 00Z.
&&
.FIRE WEATHER...
Issued at 229 PM MDT Sat Sep 7 2019
Concerns look to be on the low side into the middle of next week
with sufficiently high min RHs. There will also be a good chance for
widespread wetting rain Sunday afternoon and evening as a strong
disturbance passes across the area. Some windiness around the mtns
Monday afternoon.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&
$$
SHORT TERM...RE
LONG TERM...RE
AVIATION...MB
FIRE WEATHER...RE
Area Forecast Discussion
National Weather Service Indianapolis IN
1111 PM EDT Sat Sep 7 2019
.UPDATE...
The AVIATION Section has been updated below.
&&
.SYNOPSIS...
Issued at 256 PM EDT Sat Sep 7 2019
High pressure over Illinois and Missouri will push across Indiana
tonight...providing an evening of dry weather into early Sunday.
An upper level weather disturbance and the arrival of a warm
front will from the southwest is expected to increase clouds early
on Sunday as well as bring chances for showers or a thunderstorm
on Sunday afternoon.
Dry weather is expected to return on Monday and most Tuesday
before evening warmer and more humid weather arrives for mid-week
along with some chances for thunderstorms.
&&
.NEAR TERM /Tonight/...
Issued at 256 PM EDT Sat Sep 7 2019
Surface analysis early this afternoon shows high pressure in place
across Missouri and Illinois...extending east across Indiana. Low
pressure systems were in place across South Dakota and Kansas.
GOES16 shows some CU across SE Indiana. Water Vapor shows an upper
low over Montana...with embedded short waves over ND...MN And IA
resulting in showers. Surface flow across Indiana was light and
from the northwest and dew point temps were in the mid 50s.
THE GFS And NAM push the short waves and forcing upstream to the
northwest toward Indiana overnight...arriving after 06Z. Time
height sections show moderate saturation through the column by
12Z...continuing through 18Z ...along with lift aloft. 300K GFS
isentropic surface fails to show much lift until Sunday. Thus
will trend toward a mostly clear evening with increasing clouds
overnight. Will trend lows at or above the NBM with increasing
clouds.
&&
.SHORT TERM /Sunday through Tuesday/...
Issued at 256 PM EDT Sat Sep 7 2019
As previously mentioned...the GFS and NAM project a short wave
toward Indiana on Sunday. Time heights show moderate saturation
through the day on Sunday with lift in place through the morning
hours. By afternoon the GFS 305K isentropic surface begins to show
some up glide also with specific humidities over 8 g/kg. Forecast
sounding do fail to hint at any deep saturation. However the HRRR
suggest some precip over Illinois poised to posh in to Indiana
within the NW flow on Sunday morning. Further forcing appears
available at the surface as a warm front sets up over the southern
parts of the state. Thus will keep best pops on Sunday contained
to the northern parts of the forecast area through the morning as
the best forcing passes then. Small pops may be needed to be
continued into the afternoon and evening as the forcing aloft
slowly departs and moisture lingers. Will trend highs at or below
the NBM given the expected cloud cover and possible rain.
On late Sunday night and into Monday the frontal boundary drifts
farther southeast and dry air begins to settle within the column
as ridging builds across the area aloft. This should lead to dry
weather through at least Tuesday. Further support is suggested as
ridging builds across deep south extending to Indiana.
Furthermore
...the warm front surges north of Indiana by Tuesday...brining
much warmer and more humid air into Central Indiana for the middle
of the week. Thus will continue at that time to try to trend
toward a dry forecast along with temps above the NBM.
&&
.LONG TERM /Tuesday night through Saturday/...
Issued at 304 PM EDT Sat Sep 7 2019
The long term will begin with an upper ridge of high pressure in
place over central Indiana and warm temperatures aloft. This
should keep mainly dry conditions in place over the state, along
with well above normal temperatures with highs in the middle 80s
to lower 90s and low in the upper 60s to lower 70s through
Thursday night. A few storms will be possible each afternoon
during peak heating across northern parts of the area getting
further away from the surface high over the southeastern U.S. A
cold front could move through the area on Friday bringing slightly
cooler temperatures along with chances for thunderstorms.
&&
.AVIATION /Discussion for 080600z TAF Issuance/...
Issued at 1111 PM EDT Sat Sep 7 2019
Good confidence in mostly or all VFR conditions through the TAF
period. The GFS LAMP suggests fog is possible 09z-13z but the SREF
does not. The GFS LAMP has been on the pessimistic side the last few
nights when fog did not develop. So, will leave it out. Otherwise,
showers are possible today especially after 14z, with the best
chances at LAF and HUF.
Light and variable or calm winds overnight will become northeast and
east around 6 knots after 18z.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Puma
NEAR TERM...Puma
SHORT TERM...Puma
LONG TERM....CP
AVIATION...MK
Area Forecast Discussion
National Weather Service Marquette MI
634 PM EDT Sat Sep 7 2019
.SHORT TERM...(This evening through Sunday)
Issued at 405 PM EDT SAT SEP 7 2019
WV imagery and RAP analysis indicated a mid/upper level trough from
James Bay into the eastern Great Lakes resulting in nw flow through
the northern Great Lakes. A shortwave trough was located over
eastern Montana with a an associated trough extending into the
central PLains. WAA ahead of the trough was bringing mid/high clouds
into the region. Otherwise, Cool air with with 850 mb temps around
4C supported abundant inland cu/sc over Upper Michigan.
Tonight, Although 850 mb temps dropping to around 2C with lake temps
in the 13C-15C range would provide only marginal instability,
inversion heights to around 7k ft may still support some sct/isold
lake effect showers. Any pcpn should remain over north central Upper
Michigan downstream from developing northeast low level flow.
Otherwise, clouds should limit temp drop inland with readings mainly
in the upper 30s to lower 40s while readings around 50 are expected
along Lake Superior.
Sunday, High pressure will continue to dominate the area with light
easterly winds. Some light lake effect showers may linger early
north central. Even with gradual clearing into the afternoon, the
cool airmass with 850 mb temps again around 4C, will limit highs to
the lower 60s inland and the upper 50s along Lake Superior.
.LONG TERM...(Sunday night through Saturday)
Issued at 437 PM EDT SAT SEP 7 2019
An active period with the potential of mdt to hvy rain events will
be setting up next week as subtropical ridge builds over the se
CONUS. This ridge will not only help to steer a series of
shortwaves, of which at least one will be quite vigorous, from off
the ne Pacific, across the western CONUS and then ene toward se
Canada, but it will also allow for open flow off the Gulf of Mexico
to be taken advantage of by the shortwaves. Initially, in the early
to mid week period, the combination of ridging shifting from nw
Canada to central Canada and the building ridge over the se CONUS
will result in confluent flow across se Canada. Right entrance of
the jet resulting from the confluence will play a role at times in
pcpn generation across the Upper Mississippi Valley/western Great
Lakes thru the midweek period. Although the confluence will also
result in the first shortwave weakening/shearing into se Canada Tue,
this wave will still likely produce mdt/hvy rainfall across Upper MI
Mon night/early Tue. As the Canadian ridge continues eastward and
links up with the se ridge, a stronger trof over the western CONUS
Tue will lift across the northern Plains Thu and into northern
Ontario Sat. This system will bring another round of mdt/hvy
rainfall to Upper MI at some point in the Thu/Fri time frame. The
next trof will then shift toward the western Great Lakes next
weekend, bringing the potential of another round of mdt/hvy pcpn
during the latter part of the weekend. As for temps, readings next
week will fluctuate either side of normal with warmer days and
cooler days dependent on shortwave timing. At the moment, no
significant departures from normal are apparent.
Beginning Sun night, sfc high pres center will be e of Lake Superior
and will be drifting e thru the night, but ridging will still extend
back into Upper MI. Since precipitable water is not too much blo
normal to enhance radiational cooling, did not utilize coldest
guidance, of which there are a few showing min temps in the upper
20s in the traditional cold spots. For now, have temps as low as
freezing, though mid/upper 30s should largely be the rule across the
interior. Expect some frost. If light se winds off the sfc become
just strong enough, low clouds may begin to develop into central
Upper MI during the overnight as warmer/moist lake modified air
moves inland into the chilly air over the land.
First shortwave moving out of the western CONUS will lift toward the
Upper Mississippi Valley Mon. In response, 40-50kt low-level jet
shifting out across the Plains will result in strong waa/isentropic
ascent/moisture transport and thus shra spreading into the Upper
Mississippi Valley and toward Upper MI during the day. Leading edge
of the shra may reach the far w late in the day. Otherwise, expect
increasing clouds and southeasterly winds Mon.
Strong waa/isentropic ascent/theta-e adv/moisture transport shift
across Upper MI Mon night. Under the advection, precipitable water
increases to 1 and 2/3rds of an inch or more (200pct or more of
normal). Given the strong forcing/moisture advection, widespread
shra and mdt/hvy rainfall are likely. ECMWF for many runs has been
remarkably consistent on its axis of heaviest rainfall across Upper
MI, and other than some relatively minor shifts in heaviest rainfall
placement in the last several runs of the GFS/CMC, consensus of
those models also support the axis of heaviest rainfall cutting
across a large part of the fcst area. Probably looking at a 0.75 to
1.5 inch rainfall across the fcst area late Mon into early Tue.
Instability aloft up to potentially several hundred j/kg will be
advecting into the pcpn area, so at least some isold embedded
thunder will occur as well. Shra will diminish/end from wsw to ene
late Mon night/Tue morning. Depending on lingering cloud
coverage/daytime heating during the day Tue, enough instability may
build to support some sfc based aftn convection.
Frontal boundary associated with the first shortwave will end up s
of the fcst area Tue night thru Wed night. How far s this front
moves and the position of the upper jet in the confluence zone just
to the n will determine whether additional rainfall occurs Tue night
thru Wed night. With any subtle shortwaves in the flow, there will
be clusters of shra/tsra with mdt/hvy rainfall tracking along the
vcnty of the front during this time. Right now, it appears position
of the forcing features will be far enough s to keep much of the
pcpn s of Upper MI, but it wouldn`t take much northward shift to
bring more rainfall into the fcst area. Southern Upper MI will have
the best chc of seeing pcpn at times Tue night thru Wed night.
For the time range into the model runs, medium range model agreement
has been quite good for the stronger trof shifting from the western
CONUS Tue to the Northern Plains Thu and to northern Ontario by Sat.
This vigorous shortwave trof will bring another surge of strong
theta-e adv/moisture transport/isentropic ascent across Upper MI Thu
into early Fri. Precipitable water will again increase to around 1
and 2/3rds inches. So, another period of mdt/hvy rainfall looks
likely Thu into early Fri. After a break on Sat, next system may be
approaching on Sun to bring more shra.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 634 PM EDT SAT SEP 7 2019
It will be mostly VFR through the forecast period at all sites.
There will be MVFR conditions at times though at SAW, IWD and CMX
with some upslope flow and colder air causing some lake effect
clouds.
&&
.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 405 PM EDT SAT SEP 7 2019
Winds will be mostly under 20kt for tonight/Sun as high pres passes
over or just n and e of Lake Superior. Winds will then be on the
increase later Mon into Tue as the high pres departs and low pres
tracks e toward the Upper Mississippi Valley. Not out of the
question that there could be a period of e-se gales as the low
approaches Mon night into Tue morning. Gales may again be
possible by late Thu into early Fri as a strong low pressure
system approaches the area.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
SHORT TERM...JLB
LONG TERM...Rolfson
AVIATION...07
MARINE...JLB
Area Forecast Discussion
National Weather Service Spokane WA
447 PM PDT Sat Sep 7 2019
.SYNOPSIS...
Cool and unsettled weather arrives tonight and Sunday, and will
linger through at least the middle of next week. Several
opportunities for precipitation will be found, along with the
potential for some thunderstorms. Drier conditions are possible
toward Thursday.
&&
.DISCUSSION...
...Heavy rain possible tonight across portions of central
Washington...
Tonight: Shortwave ridge is getting pushed east as the negatively
tilted trough is beginning to moving ashore. High clouds are
moving in ahead of tonight`s system...which has kept our
temperatures down. Pesky stratus just burned off around 11am in
Sandpoint, and it is still cloudy in Bonners Ferry. Did adjust max
temperatures down several to many degrees across the area based
off what temps were around noon. Thicker clouds will move in
overnight, especially across central WA and so have increased min
temperatures.
Have issued a flash flood watch for Chelan and Okanogan Counties
in central WA from 8pm tonight through 8am Sunday morning. This
trough is taking a negative tilt as it moves into the area
tonight. This is slowing down the timing of the onset of the
preciptiation through the night. The best timing of the heaviest
rain is after 11pm tonight and through the morning hours on
Sunday.
The concern is impacts on burn scars and steep terrain or deep
canyons of the Cascades. Cannot rule out debris flows, mud or rock
slides. The areas of main concern are the burn scars, canyons
around Wenatchee, Entiat, up Lake Chelan, along Highway 97, and in
the Methow Valley.
Precipitable water values of over an inch are expected. Many high
resolution models are showing showers and thunderstorms developing
overnight. These storms could produce very heavy rainfall in a
short amount of time. It is difficult to say how much, as it could
vary greatly from location to location, but some models have over
an inch of rain in less than 6 hours across portions of Chelan
and Okanogan counties. The moist conditions coupled with some
vorticies moving up overnight will be enough to get stuff going.
Overnight the threat of showers and thunderstorms will expand into
other portions of central WA...east onto the Waterville Plateau,
Moses Lake area, and maybe as far east as the Lincoln and Adams Co
borders; but precip amounts will be less. Not as confident in the
wind potential with these showers and thunderstorms overnight,
but the HRRR is showing some winds moving up Grant and Douglas
counties after midnight with gusts up to 40 mph possible. /Nisbet
Sunday and Sunday night...An upper level trough that can bee seen on
satellite at the time will move slowly across the Cascades
tonight and is not expected to be east of the Panhandle until
Sunday night. Forcing with the cold front is quite impressive, as
is, the instability. Southerly flow ahead of the cold front will
tap into deep pacific moisture. in fact model guidance indicates
to moisture field will be about 3 standard deviations above
normal. The impacts will be widespread showers and embedded
thunderstorms. it looks like just about all areas will get quite
wet with the basin picking up 0.10-0.20 of rain by early Sunday
evening. There will be widespread 0.25-0.50 across the lower
elevation and the mountains may see 0.50-1.00. So this is a wet
system indeed. Temperatures will drop into the 60 to lower 70s
with 50s in the mountains which will be 5-8 degrees below average.
We can also expect gusty southwest winds Sunday afternoon with
the cold front.
Monday through Wednesday...A deep, cool and unstable upper level
low will remain over the region through Wednesday. The low then
gets pushed east allowing high pressure to build into the region.
This is a very unstable pattern and it will only take weak short
wave disturbances to kick off showers and thunderstorms. For now
it appears these waves will wrap around the periphery of the
forecast, which puts the focus of the best convection over the
mountains. Moisture will also get advected into the region with
each wave so any showers or thunderstorms will have the potential
to drop moderate to heavy rain in a short period of time.
Temperatures will be in the 60s to mid 70s which is well below
normal.
Thursday through Saturday...Model guidance is in agreement of high
pressure building into the region Wednesday night and Thursday
with another deep low pressure system along the B.C coast. This
will bring a short warming and drying trend trend to the region.
Them model guidance falls apart so this forecast leans in favor of
the ensemble models which brings an open wave through the Pac NW
on Friday/Friday night. This will increase the chances of showers
and possibly thunderstorms for the weekend. The trough will also
result in temperatures cooling of once again to the cool side of
average. Tobin
&&
.AVIATION...
00Z TAFS: Increasing clouds through the late afternoon as cold
front is moving in from the west. A threat of showers and
thunderstorms develops near the Cascade later this evening and
expands east of the Cascades overnight, with the best threat
remaining near EAT/MWH. Heavy rain is expected with these storms.
Chances move toward the remaining TAF sites overnight, but the
better risk develops Sunday morning. MVFR conditions possible in
heavier precipitation. /JDC
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 57 65 50 69 48 71 / 10 80 60 30 30 30
Coeur d`Alene 57 65 51 67 47 70 / 0 90 90 40 20 30
Pullman 55 61 46 67 46 68 / 10 90 50 20 20 50
Lewiston 63 66 55 74 54 72 / 10 90 50 20 20 50
Colville 53 72 45 73 43 75 / 10 80 100 60 60 30
Sandpoint 54 69 50 65 45 69 / 0 90 100 70 40 40
Kellogg 58 64 53 64 49 68 / 0 90 100 50 30 40
Moses Lake 62 74 50 74 50 72 / 80 80 20 20 30 20
Wenatchee 65 73 58 72 56 70 / 100 40 10 40 30 50
Omak 63 74 53 71 52 71 / 90 90 60 50 50 50
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...Flash Flood Watch from 8 PM PDT this evening through Sunday
morning for East Slopes Northern Cascades-Okanogan
Highlands-Okanogan Valley-Wenatchee Area.
&&
$$
Area Forecast Discussion
National Weather Service Reno NV
608 PM PDT Sat Sep 7 2019
.UPDATE...
Updating to increase the threat of for most of western Nevada.
Showers and isolated thunderstorms are forming across much of
central Nevada early this evening. The broad area of lift is as
far west as the Pine Nuts and Virginia Range with notable
development out the window. Recent HRRR ideas are also notable in
bringing the threat of showers and storms farther west this
evening. Most areas near and east of Highway 95 will receive some
rain this evening, with a lesser chance farther west to the Pine
Nuts and Virginia Range. Amounts will be light as the showers are
moving, but locations that receive multiple showers may receive as
much as a half inch. X
&&
.PREVIOUS DISCUSSION... /Issued 236 PM PDT Sat Sep 7 2019/
SYNOPSIS...
An approaching area of low pressure will bring breezy conditions,
with thunderstorm chances mainly over west central Nevada this
evening. A cooling trend with dry conditions is expected Sunday
and Monday, then a colder weather system may bring another chance
for showers and thunderstorms on Tuesday. Dry and warmer
conditions then return for the later portions of next week.
DISCUSSION...
The main change in the upcoming week`s weather was pushing this
evening`s thunderstorm threat farther east across west central NV,
with the best overall chance from US-95 eastward. Then for
Tuesday, we expanded the shower chances a bit farther south to
include parts of the Reno-Tahoe vicinity and included possible
thunder.
For this evening, the slower timing of the upper trough passage
and its associated upper jet support, along with the widespread
cirrus coverage ahead of the trough passage, has reduced the
potential for thunderstorms in far western NV and eastern Mono
County. The majority of the latest guidance sources favor the
thunderstorm chances to be limited to areas east of a Gerlach-
Fernley-Yerington line, with the greatest coverage east of US-95.
Some storms will be capable of producing heavy rainfall, gusty
winds and small hail, especially east of US-95 where multiple
cells could track over the same area through this evening and even
into the overnight hours.
Otherwise, breezy conditions this evening will likely carry smoke
from the Walker Fire across eastern Lassen-Plumas counties and
into parts of western NV, favoring the Pyramid Lake area and into
west central NV tonight (visibility over Lovelock-Fallon is
currently reduced to 4-5 miles). Lighter haze and smoke may also
be noticed over parts of the Reno-Sparks vicinity, mainly north of
I-80 later this evening and overnight. If the fire continues to
burn actively on Sunday, similar areas are likely to receive smoke
and haze again, although with lighter winds less smoke would
reach Lovelock-Fallon.
For Sunday and Monday, a gradual cooling trend is expected behind
tonight`s trough passage, while another low pressure system moves
into the Pacific Northwest. Cloud cover is likely to increase
Monday especially north of I-80 as the low starts to dip southward.
There is a slim possibility (although not yet included in the
forecast) that very light showers could occur near the Oregon
border by Monday afternoon-evening.
The next chance for showers is on track for Tuesday, as this low
reaches its southernmost position. Northeast CA-Northwest NV will
have the best shower chances, but some precip could reach farther
south to near the I-80 corridor of eastern CA and far western NV.
Although temperatures will be even cooler (highs only in the 60s
to lower 70s for lower elevations), increased forcing along the
trough and cold front looks sufficient to produce isolated
thunderstorms.
From Wednesday through next Saturday, dry conditions return as a
flat ridge sets up overhead. This will also allow temperatures to
warm back to the mid 80s by Friday-Saturday. Another trough may
bring cooler conditions later next weekend, but there is a wide
range of scenarios in the medium range guidance, with some keeping
the ridge and warmer conditions over CA-NV for a longer time. MJD
AVIATION...
Breezy conditions will continue through around 04z this evening
with peak gusts near 25 kt. There are also chances for showers
and thunderstorms this evening through late tonight, although the
main terminals are unlikely to be directly impacted. The best
chances will be east of Highway 95 but isolated storms are
possible as far west as Fernley and Yerington.
Winds decrease Sunday with dry conditions through Monday. Breezy
conditions are likely to return Monday afternoon-evening as
another trough of low pressure moves over the region. This next
trough may also produce showers near and north of I-80 on Tuesday.
MJD
FIRE WEATHER...
Gusty winds are likely into the evening hours as a trough of low
pressure lifts through the region. Gusts could reach 25-30 mph
with wind prone areas closer to 35 mph. Humidity levels should
be rising this evening...but there could be small areas in the
lower valleys of northeast California and western Nevada that see
brief critical conditions. This will not be widespread enough for
Red Flags. Even with higher humidity levels...the gusty winds
could carry any new or existing fires through grass.
Ridge lines and unsheltered valleys and slopes will be vulnerable
to a wind shift this evening as the prevailing direction
switches from south-southwest to west-northwest. Breezy west winds
are possible again Sunday...but the gusts should be lighter than
today. Another trough of low pressure approaching Monday night
will cause an increase in winds once again for late Monday into
Tuesday.
Thunderstorm chances late this afternoon and this evening are
mainly east of Highway 95. The farther east any storms form...the
better chances for wetting rains...but dry lightning strikes are
possible outside of any cores.
The trough Tuesday could produce some storms...but these would be
very isolated in nature.
&&
.REV Watches/Warnings/Advisories...
NV...None.
CA...None.
&&
$$
For more information from the National Weather Service visit...
http://weather.gov/reno