Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/23/18
Area Forecast Discussion
National Weather Service Albany NY
953 PM EDT Mon Oct 22 2018
More unsettled weather with rain showers and high elevation
rain or snow showers, is expected through Tuesday as a low
pressure system approaches from the Great Lakes and crosses our
region by Tuesday evening. Drier weather is expected for much of
the region for the second half of Wednesday into Thursday as
high pressure builds east from the Great Lakes region.
.NEAR TERM /THROUGH TUESDAY/...
Short range guidance from the HRRR and RAP suggests that
precipitation will be the light to non-existent side tonight.
Thus have lowered pops to slight chance/low chance category into
Otherwise no changes made to the forecast except to update with
For the rest of tonight and Tuesday a low pressure system will
track from the upper Great Lakes towards our region dragging the
warm front through the region late tonight and Tuesday morning
followed by a cold front for late Tuesday as the low pressure
system moves into western New England. It will become unsettled
with showers moving into the region during the overnight hours
and continuing through the day on Tuesday. While most of the
precipitation will be in the form of rain. Some light snow is
possible across the western Adirondacks late tonight into
Tuesday morning. Amounts at this time look to be light with
generally only a few tenths of an inch of snow accumulation
expected across the western Adirondacks. Total liquid
equivalents look to be on the low side as well with only a tenth
to a third of an inch in most places. Lows tonight will be in
the 30s to around 40 with highs on Tuesday in the upper 30s to
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
For Tuesday night and Wednesday an area of high pressure will be
building east from the upper Great Lakes as low pressure departs
eastward from the Canadian Maritimes. There will still be chances
for showers Tuesday night across much of the region thanks to an
upper level trough crossing the region. The coverage of showers will
be much less on Wednesday mainly confined to the northern half of
the forecast area. It will be cold enough such that some of the
showers especially across the northern mountains will be in the form
of snow. However, due to very little moisture in place with the
upper trough any accumulation will be minimal, generally an inch or
less with the greatest accumulations across the western Adirondacks
and high terrain of the southern Green Mountains. Expect Wednesday
to be a windy day as a strong pressure gradient will be across the
area between the departing surface low and high pressure in the
Great Lakes region. Wind gusts may top 35 mph at times. Lows Tuesday
night will be in the upper 20s to around 40 with highs on Wednesday
in the mid 30s to around 50.
Wednesday night and Thursday are expected to be mainly dry with the
exception of a few rain or snow showers across the northern portions
of the western Adirondacks Wednesday night. It will continue to be
chilly with lows Wednesday night in the mid 20s to mid 30s and highs
on Thursday in the upper 20s to mid 40s.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
High temperatures will remain well below normal, with low temperatures
first below normal, then near normal toward the end of the
period, with diminishing winds and radiational cooling resulting
in widespread temperatures in the 20s Thursday night which will
be almost repeated again for Friday, albeit slightly milder
with clouds on the increase. The lack of sunshine going into the
weekend followed by a good chance for rain, snow or a mix
during the weekend will keep the high temperatures in the 30s
and 40s throughout.
Low pressure developing off the southeast coast will get close
enough to bring precipitation...mainly rain...to our zones as early
as Saturday. It is expected to eventually track up into New England
and merge forces with a system originating in Saskatchewan. However,
this is more likely to affect points to our east, so some
improvement in our weather might be expected during the early part
of the work week.
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
Looking at VFR conditions at all terminals through the forecast
Weak low pressure accompanied by a trough aloft will swing
across the terminals on Tuesday. For now precipitation (all
rain) is trending toward the light side. Thus no lower than 6SM
in SHRA forecast at all terminals ex KPOU where no precipitation
Tuesday Night: Moderate Operational Impact. Chance of SHRA.
Wednesday: Moderate Operational Impact. Chance of SHRA.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: No Operational Impact. NO SIG WX.
Thursday Night: No Operational Impact. NO SIG WX.
Friday: No Operational Impact. NO SIG WX.
Friday Night: No Operational Impact. NO SIG WX.
Saturday: Moderate Operational Impact. Chance of RA...SN.
More unsettled weather with rain showers and high elevation rain or
snow showers, is expected through Tuesday as a low pressure system
approaches from the Great Lakes and crosses our region by Tuesday
evening. Drier weather is expected for much of the region for the
second half of Wednesday into Thursday as high pressure builds east
from the Great Lakes region.
Relative humidity values will recover to 75 to 95 percent tonight,
drop to 60 to 80 percent on Tuesday, recover to 85 to 100 percent
Tuesday night, and fall to 50 to 75 percent on Wednesday.
Winds will be south to southwest at 5 to 10 mph tonight and Tuesday,
and west 5 to 15 mph Tuesday night and Wednesday. Winds on Wednesday
may gust over 30 mph.
No hydrologic issues are anticipated through the week. A
disturbance looks to bring scattered to numerous showers later
tonight and Tuesday. Some snow is expected to mix in across the
higher terrain. Only light precipitation is expected with total
liquid equivalent amounts a tenth to a third of an inch. After
a few more rain/snow showers Tuesday night into Wednesday, dry
weather is expected the rest of the week with the next chance
for some wet weather occurring over the weekend.
For details on specific area rivers and lakes, including
observed and forecast river stages and lake elevations, please
visit the Advanced Hydrologic Prediction Service /AHPS/ graphs
on our website.
Area Forecast Discussion
National Weather Service Quad Cities IA IL
649 PM CDT Mon Oct 22 2018
Issued at 254 PM CDT Mon Oct 22 2018
This afternoon a cold front was located across northeast Missouri
and into central Illinois. Behind this front, temperatures held in
the 60s, but dewpoints dropped dramatically into the upper to low
30s. This has led to relatively cooler sensible weather even
though temperatures are in the 60s across the area. These low
dewpoints along with high pressure behind the cold front will lead
to the short term weather.
.SHORT TERM...(This Evening through Tuesday)
ISSUED AT 254 PM CDT Mon Oct 22 2018
High pressure will be the main driver of the short term weather as
temperatures look to be the main forecast concern. CAA will result
in cooler temperatures tonight and tomorrow as H85 temps drop from
10C to 2C by tomorrow AM. This will lead to temps in the low to
mid 30s tonight and in the 50s tomorrow. A look at all the
guidance shows that most of the forecast highs are within plus or
minus 3 of what the superblend has. As a result, went with
superblend for temps. As for low temps, superblend seems to be on
the warm side of guidance. With crashing dewpoints today seems as
though going with the low side of guidance is a good idea. Went
with a blend of the RAP with superblend.
.LONG TERM...(Tuesday Night through Monday)
ISSUED AT 254 PM CDT Mon Oct 22 2018
Long term period can be divided into two periods, a continued
blocking pattern will lead to quiet weather on the front end. The
back end of the period the block will break down and lead to
chances of rain for the weekend. This discussion will focus more
on the chances for rain than the quiet weather.
As the previous discussion mentioned, this weekend will not be a
washout across the area. There will be periods of dry with mixed
with chances for rain. One thing that does look certain though is
that the weekend will likely be cloudy with few breaks in the
clouds until later in weekend and into Monday. Two main waves are
expected this weekend. The first one Friday into Saturday, this
looks to be the best chance for precip across the area. The next
one will be later Saturday night into Sunday morning. The overall
flow looks to be rather active with numerous little waves. This
leads to a complex forecast in terms of when to forecast precip.
As a result, confidence is low in respect to the actual timing of
rain across the area.
Another wrench to throw into the forecast is the chance that
temperatures could actually be much lower than what is forecast.
This could lead to the possibility of winter like precip this
weekend. With all of the variables forecast for this weekend,
confidence is low in what may or may not happen.
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
ISSUED AT 641 PM CDT Mon Oct 22 2018
VFR conditions will prevail through this TAF cycle with light WNW
to N winds. KBRL has been reporting 1/4 to 1/2SM visibility from
haze since 4 PM CDT. This could be caused by dust kicked up from
nearby agricultural fields. However, it is likely not as severe as
the sensor is reporting. Uttech
Area Forecast Discussion
National Weather Service Green Bay WI
1029 PM CDT Mon Oct 22 2018
Updated aviation portion for 06Z TAF issuance
.SHORT TERM...Tonight and Tuesday
Issued at 213 PM CDT Mon Oct 22 2018
The latest RAP analysis and satellite/radar imagery show a dry
cold front moving across north-central WI early this afternoon.
Skies are clear across Wisconsin, but a solid area of strato-cu is
pushing southeast over far northern Minnesota, where low level
temps are colder. Some gusts up to 25 mph are occurring within
this colder airmass as well. As this colder airmass slides into
the area tonight, light lake effect precip chances and wind gusts
are the main forecast concerns.
Tonight...The cold front will continue to move southeast and exit
northeast WI during the evening. Breezy northwest winds behind
the front will usher in a much colder airmass. Delta T`s will drop
to about 12-13C over western Lake Superior. Combined with upslope
flow, should result in scattered lake effect rain and snow showers
in the snow belt of Vilas county. Do not think will see much in
the way of accumulations, since the highest mid-level moisture
will arrive during the evening when temps will mainly be cooling
from the lower 40s to the middle 30s. But perhaps could see a
small dusting on grassy surfaces overnight. Clouds will struggle
to reach into the Fox Valley due to downsloping, but did show
mostly cloudy skies developing over much of north-central WI. Unstable
conditions over the Bay and Lake will create some gusts over 25
kts on the Bay and on Lake Michigan north of Sturgeon Bay. A small
craft advisory is already in effect. Lows will mainly fall into
the low to mid 30s across the region.
Tuesday...High pressure will gradually shift toward the region,
and move into far western WI in the afternoon. Cold advection will
continue through the day, which will reinforce the thermal
troughing across the region. Combined with steepening low level
lapse rates, should see a scattered cu field develop by late
morning at most locations, after being mainly confined to north-
central WI early in the day. A few flurries may linger over the
Vilas county snow belt through mid-morning. Temps will fall back
into the upper 30s to mid 40s range.
.LONG TERM...Tuesday Night Through Monday
Issued at 213 PM CDT Mon Oct 22 2018
No major weather impacts expected through much of the extended
portion of the forecast. The next chance of significant
precipitation will be toward the end of the week into next weekend.
Tuesday night through Wednesday night: High pressure will move
across the area through this time period, both aloft and at the
surface. This will allow for dry conditions, partly cloudy skies and
relatively calm winds. These conditions will allow for some cold
temperatures Tuesday night with ideal radiational cooling.
Temperatures will remain well below normal with overnight lows
dropping into the low to mid 20s northwest to low 30s southeast.
Daytime highs will be in the mid to upper 40s.
Thursday into Friday: Return flow/WAA will kick in on the back side
of the departing high pressure system. This will lead to increasing
moisture and cloud cover across much of the CWA ahead of the next
system. Most of the day Thursday will remain dry with increasing
clouds; however, a weak shortwave is progged to slide into the area
late Thursday afternoon into the day Friday. The combination of
upper-level dynamics along with at least a weak Theta-E gradient
across central WI will allow for an increasing chance of
precipitation through this time period. Thermal profiles would
suggest the precip may even hold off into the evening hours as a low
to mid-level dry layer remains in place. There is enough moisture
and forcing aloft that this layer should saturate by mid evening,
giving the chance of a rain/snow mixture across the area into
Thursday night. While soundings initially show temps warm enough
through the lower levels to support rain, the profile is expected to
moisten/cool (due to latent heat release) enough to allow some wet
snow to mix in at times. This will especially be true over the north-
central portions of WI in the higher terrain. With temperatures
expected to hover near or just above freezing and the soil remaining
unfrozen, would not expect any major impacts. There could be some
light accumulations on grassy/elevated surfaces into early Friday
morning. By mid morning Friday and into the afternoon hours, surface
temps will warm into the upper 30s to low 40s, which will
effectively transition any precipitation over to rain showers. Not
expecting much more than a tenth of an inch of QPF.
Friday night through Sunday: A surface low progged to be over
southern Manitoba, along with an associated shortwave, is expected
to slide southeast through the Western Great Lakes Region Saturday
into Saturday night. This will then keep a surface trough/stationary
boundary across the area into Sunday, leading to an extended period
of unsettled weather. As much of the CWA is expected to remain on
the warm side of these features, lower level warm air is expected to
keep much of the precipitation in liquid form. Western portions of
the CWA, over mainly central WI, may see QPF totals around a quarter
inch, while the eastern half of the CWA will probably see a tenth of
an inch or less for this time period. A blend of the models handled
this time period and the model differences well; therefore, have
made few changes to the blend. Temperatures will remain below normal
with highs in the 40s and lows in the mid to upper 30s.
.AVIATION...for 06Z TAF Issuance
Issued at 1026 PM CDT Mon Oct 22 2018
Upper flow will continue veering more northerly overnight, in the
wake of a shortwave digging through the region. That was allowing
a large mass to drop south into the area. But the eventual
southward extent of the clouds is still in question. Kept bases
across the south VFR while the north will likely fall to MVFR and
have some sprinkles and maybe eventually a few flurries. Clouds
should become a little more widespread across the entire area
tomorrow as surface heating leads to the formation of convective
clouds during the morning.
Area Forecast Discussion
National Weather Service Melbourne FL
915 PM EDT Mon Oct 22 2018
.DISCUSSION...Very light showers developing over the Atlantic
waters as breezy onshore flow continues tonight, with some showers
pushing onshore along the Volusia County coast. Even as the winds
diminish overnight, local WRF and HRRR continue to show isolated
showers developing through daybreak. Have expanded the slight
chance of light showers for most of the waters from Vero Beach
northward. Min temps from the previous forecast are holding up
well with new guidance. Temps should fall into the mid/upper 60s
in the cities and suburbs, and low/mid 60s in rural areas.
Followed the previous forecast`s decision to go 1-3 degrees above
GFS MOS guidance at Melbourne, Vero Beach, and Ft. Pierce. 00Z
LAMP guidance shows onshore flow through the overnight at these
sites, which usually keeps temps above guidance. Only caveat would
be if conditions go calm right before sunrise allowing temps to
quickly drop several degrees. On Tuesday, cloud cover to increase
as a weak coastal trough begins to set up from the Cape northward.
.AVIATION...Mostly VFR. A very small rain chance exists along the
coast from KTIX-KDAB as isolated showers develop over the
Atlantic waters and push onshore. Considerable cloudiness will
develop late tonight into Tuesday as a weak coastal trough sets up
from around Cape Canaveral to KDAB. High level SCT-BKN deck will
also continue across the area from KMLB-KISM northward.
.MARINE...Overnight-Tuesday...High pressure shifts away from the
mid Atlantic coast and a weak coastal trough sets up from around
Canaveral northward. This will weaken the pressure gradient and
onshore winds will diminish to 10 knots or less Tuesday morning.
Observations show seas 5 feet or less currently and guidance has 4
feet or less on Tuesday.