Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/01/18
Area Forecast Discussion
National Weather Service Denver/Boulder CO
839 PM MDT Sun Sep 30 2018
.UPDATE...
Issued at 839 PM MDT Sun Sep 30 2018
Cold and moist low level flow continues to wrap around a surface
cyclone now located south of Strasburg. This will bring a threat
of fog as far back as the I-25 Corridor from Fort Collins down
into the northern sections of Denver overnight. We have expanded
the latest fog coverage to account for this. With narrow T/Td
spreads, we could see some patchy dense fog as well. There`s a
little drizzle noted over the northeast plains so have included
that most of the night.
Meanwhile, in the mountains it was still very dry and only in the
last hour or so have dewpoints responded. There may be enough
moisture advection by late tonight or Monday morning for a light
sprinkle or flurry over the mountain tops.
Tomorrow should begin a slow transition to a more moist and
unsettled weather pattern for the upcoming week.
&&
.SHORT TERM...(This evening through Monday)
Issued at 200 PM MDT Sun Sep 30 2018
Southwest flow will continue over Colorado through tonight and
Monday. Shallow cool and moist airmass over eastern Colorado will
be slow to modify and retreat. Eventually, south to southwest
winds surface winds will spread northeastward and push out the
cooler airmass. It may take until Monday morning for parts of the
eastern plains and South Platte river valley to scour out the
colder air.
Moisture will increase tonight and Monday. In addition to the
increasing moisture, a weak trough embedded in the southwest flow
will track across the Central Rockies Monday. This system is
expected to produce scattered showers and a few weak thunderstorms
over the mountains. HRRR and RAP models show some convection over
eastern Colorado, mainly south of I-76. Added some low pops to
the forecast for this.
.LONG TERM...(Monday night through Sunday)
Issued at 200 PM MDT Sun Sep 30 2018
The plume of very moist and unstable subtropical air coupled to the
remnants of Hurricane Rosa is still progged to continue its
northeast trajectory across the Four Corners region on Tuesday, and
then eventually shear out across Colorado/southern Wyoming Tuesday
night/Wednesday morning. With its passage, integrated precipitable
water values rise from around a half inch across western Colorado
late Monday night to slightly more than an inch across most of
Colorado by Tuesday afternoon. Models also show 850-500mb specific
humidities peaking over southwest Colorado late Tuesday as the last
of Rosa moves its way across the area. Lapse rates are only
marginally unstable and 700-500mb QG omega is only slightly
negative/indicating weak ascent with the passage of this feature.
With that said, orographic forcing produced by a deep south-
southwest flow should provide the addition lift necessary for
scattered to numerous showers over higher elevations of the CWA
during the Tuesday-Tuesday night time frame. Whereas east of the
mtns, sfc-500mb layer subsidence and drying the product of this same
southwest flow should keep precip chances quite low on the plains,
just plenty of mid-level cloudiness with temperatures continuing to
creep upwards.
By Wednesday, a passing shortwave ridge will lessen precip chances
for the high country and keep conditions dry and warm east of the
mtns. Temperature guidance shows Wednesday high temps on the plains
a couple degs F warmer than those on Tuesday, with low to mid 80s
both days some 10-15 degs above the seasonal norm.
By Wednesday night, could see an abrupt shift to wetter and cooler
conditions with another batch of mid-level forcing and deep upslope
flow with a rather strong cold front backing up against the Front
Range during the evening hours. Scattered to likely PoPs in order
for the Front Range and northeast plains with QPF generally under a
quarter inch, with locally up to a half inch possible with t-storms
in the northeast corner of the CWA by morning.
Thursday through Sunday, medium range models continue to trend
colder and wetter across the West with a series of shortwave troughs
digging down the West Coast and eventually carving out a broad, very
moist upper trough over the Intermountain West by the weekend. GFS
continues to be the wetter/colder of the models, although the
12z/run of the ECMWF has converged on the GFS solution. The Canadian
model still quite dry and warm through Sunday morning with strong
dry slotting around the upper trough hanging back over the Great
Basin. The GFS also shows dry slotting over ern Colorado but not
before 30-36 hours of cold and moist upslope precip along and east
of the Front Range. GFS wetbulb temps appear cold enough for a
wet snow down to around 5000 feet. We`ll see.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 839 PM MDT Sun Sep 30 2018
We are becoming more concerned with the threat of low clouds and
fog wrapping back as far south as KDEN and KBJC overnight. Low
level flow pattern supports the stratus on the plains to wrap
around in cyclonic fashion, possibly reaching KDEN by 08Z-10Z.
Visibilities down to 1/4SM and VV002 possible with the narrow T/Td
spreads and upslope flow wrapping into KDEN with shallow WNW winds
up the slope out of the South Platte River. Will have to watch
this closely for the next several hours. If it does form, we hope
to see some improvement by 13Z or shortly thereafter for the
morning rush as low level flow may attempt to turn more southerly
toward this time. Again, it might be a matter of a couple miles
whether or not DIA sees improvement.
Otherwise VFR conditions can be expected. There is just a slight
chance of a high based shower or two moving off the mountains from
the southwest by 21Z Monday.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Barjenbruch
SHORT TERM...Meier
LONG TERM...Baker
AVIATION...Barjenbruch
Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
616 PM CDT Sun Sep 30 2018
.DISCUSSION...Updated for latest aviation discussion below.
&&
.AVIATION...Tranquil conditions are becoming established within
the region, and those should last for the next several hours.
However, model guidance suggests that another overnight burst of
convection will occur and affect the aerodromes after midnight
and/or around sunrise. High cirrus debris and moderate winds will
prevail tomorrow in the wake of the convection.
&&
.PREV DISCUSSION... /issued 307 PM CDT Sun Sep 30 2018/
SHORT TERM (Now through Monday night): Precipitation is in a bit
of a lull at the moment, per KBRO radar, as activity associated
with a possible MCV out west lifts northward and offshore showers
and storms wane with the diurnal cycle. HRRR still hinting at some
redevelopment within the next few hours, which is consistent with
some additional insolation resulting from thinning cloud cover
seen on visible satellite. So, have held on to scattered PoP`s out
west early this evening but more isolated east. 12Z runs of
NAM/GFS indicating some light coastal showers possible late
tonight as well. Overnight lows should again be in the low-mid
70`s with mostly cloudy skies. With light winds, wet ground, and
following the trend of obs from last night, have added some patchy
fog to the weather grids for the northwestern ranchlands later
tonight into early Monday morning as well.
Speaking of tomorrow, H5 ridging will be gradually nosing back
westward into the region, leading to some drying of mid-levels
during the afternoon, especially for the eastern third or so of the
CWA. PW still progged to run 1.8-1.9" areawide, though, so looks
like a "sea-breezy" kind of day. Scaled back a bit on PoP`s
(reduced 10% or so), as guidance not going much above 30% anywhere,
especially eastern/coastal areas during the afternoon. With a bit
more sun, especially later in the day, high temps on Monday should
recover to near 90F along the Rio Grande (where heat indices will
near 100F for the first day of October) with upper 80s elsewhere.
Also of note, a long easterly fetch of surface winds sets up across
the Gulf by Monday. Swells at buoys around the western Gulf have
come up to about 3 feet already this afternoon, though period is
relatively short (~6 sec) thus far. Tides at Brazos Santiago Pass
running about 0.5 feet above predicted recently. Astronomical high
tides peak around midnight next couple days, so if the delta of 0.5
feet holds, water level could reach about 2.5 feet MLLW/1.0 ft.
MHHW. This could conceivably reach the dune line where the beach is
narrower on SPI, but not confident enough yet for any coastal flood
statements. Rip current risk likely become moderate on Monday, too.
Gradual column drying continues into Monday night, with only
isolated light showers (at best) expected. Min temps for Tuesday
morning nudge up a couple of degrees, to the mid-upper 70s.
LONG TERM (Tuesday through Sunday): 500 mb high pressure will
begin to build over the Southeast U.S. and edge into East Texas
through the middle of the week. This should bring much drier air
and subsidence to Deep South Texas, however, ample moisture for
scattered showers and thunderstorms will linger through at least
Tuesday. The GFS brings drier air in quicker than the ECMWF with
12-hour PoPs around 20 to 30% and the ECMWF keeping percentages of
around 50 to 60%. Have leaned on the drier side with the high
expected to influence our pattern as early as Monday. The rest of
the week, more seabreeze-like convection is expected with light
easterly flow and much shallower moisture. The best chances of
rain will be along the coast and over the marine areas. The
surface high will stretch across the northern Gulf with potential
for increasing swells due to persistent E to ESE winds. Tides have
been running around 0.5 feet above predicted and we could see
minor coastal flooding around high tide cycles, which are
currently in the late evening. By mid week, winds shift to a more
typical SE flow, which would drop swells back down.
Aside from low-end rain chances inland, temperatures will be
several degrees above normal. Have increased afternoon highs just
slightly up about a degree with highs ranging from the low to mid
90s. Dry air and subsidence around the high should also allow
areas to dry out after recent heavy rainfall.
MARINE (Now through Monday night): Light-to-moderate onshore winds
will be maintained through the period as high-pressure ridging
extends into the Gulf from the southeastern U. S. high. Swells at
offshore buoys have built to around 3.0 ft. this afternoon with a
period around 6 seconds. Wave model guidance doesn`t show this
building much higher, though, even with the developing easterly
fetch across the Gulf, so combined seas should remain at 4 ft. or
less. Scattered showers and thunderstorms become more isolated by
later tomorrow and tomorrow night.
Tuesday through Sunday: A series of surface lows developing in the
Plains will periodically tighten the pressure gradient across the
Western Gulf, increasing winds and building swells. Not expecting
any Small Craft Advisories, but "exercise caution" conditions
will be possible towards the end of the week and into the weekend.
With shallow moisture lingering across the region, slight chances
of showers and thunderstorms will be possible each day.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...None.
&&
$$
This product is also available on the web at:
HTTP://WEATHER.GOV/RGV
Area Forecast Discussion
National Weather Service Dodge City KS
632 PM CDT Sun Sep 30 2018
...Updated Aviation Discussion...
.SHORT TERM...(This evening through Monday)
Issued at 222 PM CDT Sun Sep 30 2018
Quite the temperature gradient across SW Kansas. Just between Ford and
Finney counties was a 20-30 degree temperature difference. This gradient
is association with a frontal boundary and related stratus that extends
from Liberal to Garden City to Larned. Forecast soundings across the
northern zones do suggest the potential for fog and drizzle this evening
and through the overnight hours. Otherwise, this front will continue
to move south along with cooler air. Lows tonight will range from the
40s northwest to 60s southeast. Other than the drizzle, the rest of
the forecast area will remain dry.
Tomorrow will be another tricky forecast temperature day. Stratus will
once again be a concern across the northern zones. I have cooled down
the northern zones to upper 60s and this may be a bit too warm should
the stratus be stubborn again. Elsewhere, 80s to near 90F is expected,
particularly as one heads closer to the Oklahoma state line.
.LONG TERM...(Monday night through Sunday)
Issued at 222 PM CDT Sun Sep 30 2018
For Tuesday and Wednesday, this pesky frontal boundary mentioned in
the short term will lift well to the north with SW Kansas firmly in
the warm sector. A strong downslope flow pattern is expected Wednesday
with widespread 90s in the forecast. Truth be told, given how dry it
has been recently, the forecast highs for Wednesday might be a degree
or two too cold. It is an excellent downslope pattern and the furnace
southwesterly winds are expected.
Beyond this, a cold front moves through late Thursday. Moisture looks
to be shunted off to the southeast and east, so there is only low chances
for showers and thunderstorms. The EC is still showing a much stronger
cold front next weekend with stronger UL dynamics associated with a
deep shortwave trough. Time will tell. Confidence still remains low
toward the end of the extended period.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 630 PM CDT Sun Sep 30 2018
Models in decent agreement with a surface cold front moving slowly
across south central Kansas tonight and the MVFR/IFR ceilings
behind this frontal boundary expanding/lowering through the
overnight hours. Based on 22UTC observations at Hays the near term
models appear to be underestimating the fog potential early
tonight in north central Kansas. At this time will still follow
the general trend of fog expanding after sunset across north
central and southwest Kansas but did begin the 00z TAFS at HAY
with fog and introduce some MVFR visibilities at Dodge and Garden
City quicker than what the latest HRRR suggests. Also given the
expected northeast winds at 10 knots or less overnight some dense
fog will be a good possibility but at this time where this will
occur is still somewhat unclear. Did go with LIFR visibilities at
Hays by 06z. Will monitor and adjust the MVFR visibilities if
needed at Garden City and Dodge City that is currently expected
after 03z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 50 83 64 87 / 0 0 0 10
GCK 50 80 60 87 / 0 0 0 10
EHA 49 89 62 88 / 0 0 0 10
LBL 49 89 62 88 / 0 0 0 10
HYS 49 68 58 86 / 30 10 10 0
P28 61 89 66 87 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Sugden
AVIATION...Burgert
Area Forecast Discussion
National Weather Service Grand Rapids MI
748 PM EDT Sun Sep 30 2018
LATEST UPDATE...
Aviation
.SYNOPSIS...
Issued at 330 PM EDT Sun Sep 30 2018
An active weather pattern is expected over the course of the next
week for the Great Lakes region. Low pressure systems moving
through the area will bring bouts of showers and occasionally
thunderstorms. The main impact for Southwest Lower Michigan will
be heavy rain and the threat of some minor flooding. The first
threat for heavy rain will come with a warm front located across
the area tonight and then with a low moving along the front Monday
night. Additional rainfall will come Wednesday night with a cold
frontal passage. A couple of different low pressure systems Friday
and Saturday will bring more rain. Temperatures this week will be
near to above normal for the first week of October in the 60s into
the 70s for highs.
&&
.DISCUSSION...(This evening through next Sunday)
Issued at 330 PM EDT Sun Sep 30 2018
The main item of concern in the 7 day forecast is the threat for
locally heavy rain. The good thing is rivers are in the normal
range for the most part with plenty of room for rise before we get
to bankfull. Smaller creeks and streams are likely going to see
rises with the potential for some ponding of water in low lying
areas in the heavier bursts of rain.
The first two main bouts of rain will come tonight and again
Monday night. It will rain on Monday too though. A warm front
situated across Southern Lower Michigan this evening will remain
near the Michigan/Indiana line both tonight and for much of
Monday. A low level jet hitting the 850mb warm front aloft will
focus the heavier rain across our forecast area. This setup is our
typical heaviest rain setup. The NAM has a band of 1-2 inches
along and north of the I-96 corridor tonight with additional
heavier rain into Monday. The 12z HRRR is similar with 1-2 inches
tonight with more coming tomorrow. By 00z Monday evening, the HRRR
has a 3-4 inch swath through the area. A good surge of moisture
out of the south on a 30-40 knot LLJ will push PWAT values into
the 1.25 to 1.50 zone. These values are over the 90th percentile
for this time of year. Bottom line, we are concerned about a swath
of heavier rain tonight into Monday that will likely reach 1-3
inches in spots, with higher amounts possible. Given antecedent
conditions being fairly dry will not be issuing any hydro
headlines at this point.
Another round of heavier rain will come Monday night as a weak low
pressure area rides northeast along the front. Monday night will
have more in the the way of dynamics in play as a 500mb shortwave
swings east through the area. The low level jet ramps up further
and reaches 40-50 knots. PWAT values surge further to close to
1.75 inches which would by near max values ever recorded this time
of year based on the SPC sounding climatology for KDTX. The heavy
rain threat obviously continues for Monday night and based on what
falls in the next 24 hours, we may need hydro headlines in terms
of an areal watch potentially for Monday night. The swaths of
heavy rain looks to be fairly narrow, but if it is a wider zone
headlines are possible.
In terms of severe weather potential, the threat does not look all
that great given instability is rather low. CAPE values surge to
around 1000 j/kg Monday evening, especially in the southwest
towards BIV and LWA. The shear is impressive with 0-6km bulk shear
near 50 knots and a lot of low level helicity. The issue is
instability may be lacking. On the upside, we will have a warm
front in the area and a low moving along it. We will have to
monitor the amount of clearing and instability Monday afternoon
which will may advect in from the south and be in place for the
evening. At this point, I feel our severe weather prospects are
low.
The front drops south of the area on Tuesday only to come back
north on Wednesday. Rain is in the forecast on Wednesday with the
warm front with higher pops on Wednesday night with a cold frontal
passage. Additional rain chances are in place for Friday and
Saturday as multiple low pressure systems ride back into the area
from the southwest. Hydro issues may continue to creep up based on
our chances for rain right through the 7 day forecast and
potentially beyond.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 750 PM EDT Sun Sep 30 2018
For the most part IFR ceiling will prevail at all taf sites
into Tuesday. The I-94 TAF site were closer to the front so the
ceilings lifted to VFR but the frontal wave has moved east and
that will allow the front to sage south overnight. So even JXN
will be IFR by 02z or so. AZO and BTl as of 2340z have become IFR
(low clouds moved back in). The front is expected to push north
tomorrow afternoon into tomorrow evening. So, once again the I-94
TAF sites may see ceiling lift some once again.
As for precipitation, the areas of scattered light rain will be
around till around 04z or so. Then a more solid area of rain will
move over the all of the TAF site. As another wave on the front
tracks just south of the area during the mid morning hours
thunderstorms with steady moderate to heavy rain is possible
across all TAF sties. Once that wave moves east the heavy rain
will move out but some drizzle or light rain will linger into the
afternoon. Expect additional heavy rain Monday night into Tuesday
morning.
&&
.MARINE...
Issued at 330 PM EDT Sun Sep 30 2018
An active weather pattern will affect Lake Michigan as well.
Stronger low pressure systems moving through the Great Lakes will
create higher winds and therefore larger waves. Tonight, fairly
stiff east winds over 20 knots will build larger waves offshore,
but not expecting them to occur in the 5 mile wide nearshore zone.
Waves will build to 1-3 feet or even 2-4 feet at times through
Tuesday, but expecting conditions to remain below Small Craft
Advisory criteria.
Wednesday into Wednesday night in the next time frame we may need
a Small Craft Advisory in strong south flow. So, the zones north
of Holland will be most likely to see waves over 4 feet.
&&
.HYDROLOGY...
Issued at 148 PM EDT Sun Sep 30 2018
Despite some areas reporting nearly 1 inch of rainfall over the last
24 hours, we continue to see rivers remain fairly steady this
afternoon. Additional rainfall is expected for central lower MI
through early Tuesday with up to 1 to 3 inches possible. Within bank
rises are expected for most rivers. A swath of locally higher rainfall
greater than 3 inches is still not out of question, and could result
in the greater potential for minor flooding particularly in smaller
rivers and streams.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&
$$
SYNOPSIS...Duke
DISCUSSION...Duke
AVIATION...WDM
HYDROLOGY...Duke
MARINE...Duke
Area Forecast Discussion...UPDATED
National Weather Service Gray ME
1106 PM EDT Sun Sep 30 2018
.SYNOPSIS...
A frontal boundary will move south Monday morning before
stalling. On Tuesday it lifts north bringing more rain.
Wednesday high pressure builds in, followed by a cold frontal
passage Thursday night. High pressure builds into New England
late in the week and early next weekend before another front
approaches from the northwest.
&&
.NEAR TERM /THROUGH MONDAY/...
Update...Mainly adjusted PoP to slow timing of likely precip
into the area until after 2 AM. May see some showers or
sprinkles sneak into Nrn NH prior to then...but measurable
precip should wait until later. Used a time-lagged blend of HRRR
PoP for timing. And with temps hovering near freezing and
cooling temps aloft of MWN...I have added some wet flakes to the
forecast on the highest summits of the Whites.
Previous discussion...Models in good agreement allowing a
frontal boundary to drift southward across the area tonight.
Along the boundary some light rain will develop over northern
areas later in the evening and then spread to southern areas
later at night. Accepted POPs from a blend of the NAM/GFS. Temps
will be warmer tonight due to the mixing and clouds. Accepted
blended temps off the models.
&&
.SHORT TERM /MONDAY NIGHT/...
The light rain drifts south with the boundary and lingers into
the morning over southern areas. Total QPF from RFC for this
system was accepted, which was mostly less than .10 inches.
The front stalls just south of the area by Monday afternoon
allowing a weak ridge of high pres to briefly build N-S into the
region. Clouds will linger. Monday will be cool with highs in
the mid to upper 50s.
Monday night high pres moves east into the maritimes as the
next stronger short wave races east from the midwest and pushes
the low and mid level baroclinic zone to our south to drift
north and strengthen as warm moist air in the mid levels pushes
north over the boundary. This will set the stage for a
widespread rain event to develop Monday night that will continue
into the extended period of the forecast. RFCQPF handles this
well. Blend of temps guidance accepted which gives overnight
lows in the 40s north to lower 50s south.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
A fast flow will continue with the jet stream rapidly sending
weak systems across the CONUS. Models attempting to time each
impulse in the fast flow.
Low pressure will exit the Great Lakes region on Tuesday. An
easterly winds will likely develop allowing some moisture to
arrive off the Gulf of Maine. Otherwise, a fast flow aloft will
mainly be from the southwest. Showers will cross the region
through Tuesday night, bringing up to an inch of new rainfall to
portions of Maine and New Hampshire.
A weak ridge of high pressure will make a brief return to the
region on Wednesday. Temperatures will moderate as well with
readings well into the 60s.
A strong cold front will approach the region from the Great
Lakes area on Thursday. This will allow for a band of showers to
cross the region from northwest to southeast during the
afternoon and early evening hours. Temperatures ahead of the
front will reach the lower 70s over southern interior areas
Thursday afternoon with H8 temperatures around +16C. Ridging and
warm temperatures aloft may prevent thunderstorms during this
period with relatively unimpressive instability across the
region.
High pressure will then build south from Canada for Friday and
the first part of next weekend. A front over the Saint Lawrence
River Valley may bring more showers to northern portions of
Maine and New Hampshire late in the weekend.
Confidence levels remain relatively low for the details and
timing in the shower activity for this week due to the fast flow
aloft.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
Short Term...VFR conditions expected thru the early morning
hours...about 09z. SHRA will move in from the W...but I do not
think MVFR will be more widespread until around 12z. That area
of SHRA sinks Swd thru the day...allowing Nrn terminals to
improve back to VFR. Some hints of stratus near the coast mid
morning to early afternoon Mon...but not ready to bite and put
in the TAFs just yet. Areas of MVFR/IFR conditions develop Mon
night in more widespread developing RA.
Long Term...Expect areas of MVFR conditions in showers and
patchy fog Tuesday, Wednesday and again Thursday evening.
&&
.MARINE...
Short Term...Winds/Seas remain below SCA conditions through Mon
night although seas build to around 5 ft over the outermost
waters toward Tue morning.
Long Term...SCAs are possible Tuesday into Wednesday and again
on Friday.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...None.
NH...None.
MARINE...None.
&&
$$
NEAR TERM...Legro
Area Forecast Discussion
National Weather Service Pueblo CO
308 PM MDT Sun Sep 30 2018
.SHORT TERM...(This evening through Monday)
Issued at 308 PM MDT Sun Sep 30 2018
Currently...
Boundary made it all the way to the mtns and max temps over the
lower elevations have remained cool. Temps out in Kiowa county at 2
pm were in the upper 50s while mid 70s were noted over the
Walsenburg area. Warmest temps were actually in the mid ark rvr
valley and wet mtn valley where readings were in the upper 70s. San
Luis Valley was generally in the M70s. Low clouds were still hanging
tough along the CO/KS border.
Tonight...
Main concern is how far west the clouds will make it back. HRRR
shows low clouds making it as far west as the wet mtns, and possibly
as far as COS. and KTAD. In the meantime, high clouds will also be
on the increase after midnight as high level tropical moisture
associated with TC Rosa moves across the SW CONUS. As for min temps,
Expect to see lows in the 40s and 50s most locations with 30s in the
mtns.
With the increasing moisture from Rosa, isolated showers will be
possible tonight along the contdvd later tonight, with some showers
possible along the Sangres towards sunrise.
Tomorrow
Lots of mid and high clouds are likely across the region, and
showers and thunderstorms will be increasing over the contdvd region
during the afternoon time period. Lower levels are likely going to
dry out per guidance and expect temps should recover into the 70s
and 80s over the plains, but these values may be a tad too warm
given the mid and high level cloudiness which is likely going to
remain over the region.
By late in the day, a few showers/isold thunder will be possible
over the Palmer Divide.
.LONG TERM...(Monday night through Sunday)
Issued at 308 PM MDT Sun Sep 30 2018
Monday night through Wednesday...The remnants of Rosa will be moving
across the CA Baja and into the Desert SW Mon night and Tue, while a
closed low associated with the Pacific trough strengthens off the CA
coastline. Continuous southwest flow aloft will draw abundant
moisture up into western CO, with the brunt of pcpn falling along
and west of the Continental Divide. There is a slim chance that the
expected rainfall could produce some localized flash flooding
concerns along the Divide for area burn scars, but will hold off on
any highlight issuance at this time and will allow following shifts
to monitor developing guidance. Expect max temps in the upper 60s to
mid 70s for the high valleys, and upper 70s to near 90F for the
plains.
Thursday and Friday...The closed low off the CA coast moves onshore
late Wed, swinging across the region on Thu. At the same time, the
upper trough slides east across the Pacific NW and northern Rockies,
dropping another disturbance southeast towards the state for Fri.
This will push two cold fronts back into eastern CO, one early Thu
morning and another Fri morning. Isolated pcpn potential spreads
across the plains as well as the higher terrain, with increased
cloud cover and cooler temps. Look for high temps in the 60s for the
high valleys, and upper 60s to upper 70s for the plains.
Saturday and Sunday...Differences between the EC and GFS models
appear over the weekend, as a longwave trough deepens over the
western half of the country and a strong closed low develops. The
GFS is farther west with this feature, while the EC places the low
moreso over UT. Both scenarios would be favorable for significant
mountain snow, and considering this is Day 6 and 7 of the forecast
period, the solutions are not that far apart. Look for highs in the
60s for most areas on Sat, then around 60F for the high valleys and
mid 60s to mid 70s for the plains on Sun. Moore
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 308 PM MDT Sun Sep 30 2018
VFR next 24 hours. Gusty southwest winds will occur this afternoon.
High clouds will increase late tonight through tomorrow morning.
Isold thunder will be possible tomorrow afternoon.
KCOS...
Anticipating VFR next 24 hours. However there is a slight chance of
some low cigs late tonight into mid morning tomorrow. For now
probability too low to explicitly mention in TAF product, but latest
guidance continues to show low clouds getting close to KCOS towards
morning. Breezy southerly flow expected this afternoon and tomorrow
afternoon.
KPUB...
Main concern will be later tonight as low cigs will likely move into
the KPUB area towards 09 UTC tomorrow and will last into mid
morning. Otherwise VFR conditions anticipated.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HODANISH
LONG TERM...MOORE
AVIATION...HODANISH
For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.php