Weather Prediction Center

National Oceanic and Atmospheric Administration

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
159 PM EST Wed Nov 04 2026

Valid 00Z Thu Nov 05 2026 - 00Z Sat Nov 07 2026

..Heavy snow over parts of the Central Rockies on Wednesday...

...Snow will develop over parts of the Upper Peninsula of Michigan
on Thursday...

...Light rain and higher elevation snow over parts of the Pacific
Northwest...

A front moving into the Pacific Northwest will dissipate while
triggering light rain and higher-elevation snow Wednesday night
into Thursday morning. In addition, rain and higher-elevation snow
will develop over parts of the Northern Intermountain Region
Thursday morning.

Moreover, a weak front over the Central Rockies/Southwest will
move eastward to the Lower Mississippi Valley by Thursday. The
system will produce heavy snow over parts of the Central Rockies
through early Thursday morning and then rain over parts of the
Central/Southern Plains by Thursday morning into late Thursday
night.

Meanwhile, rain will develop over parts of the Upper Mississippi
Valley/Great Lakes and showers and thunderstorms along and ahead
of the associated front extending from the Ohio Valley to the
Central Gulf Coast. Additionally, light snow will develop over
parts of the Upper Peninsula of Michigan overnight Thursday into
Friday morning.

The boundary will also bring rain over parts of the Appalachians
overnight Wednesday into Thursday. The rain will develop from
parts of the Northeast to the Mid-Atlantic on Thursday into
Thursday night. On Friday morning, showers and thunderstorms will
develop over parts of the Mid-Atlantic into parts of the
Southeast. Elsewhere, scattered rain showers will linger over
parts of the Central/Western Gulf Coast on Thursday into Friday.


Ziegenfelder


Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php

Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
300 PM EST Wed Nov 4 2026

Valid 12Z Sat Nov 07 2026 - 12Z Wed Nov 11 2026


...Overview...

The weather pattern will remain active for the Pacific Northwest as
a series of amplified northeastern Pacific upper troughs and
surface systems move toward the region, bringing windy periods with
heavy rain and high elevation snow. A potential atmospheric river
event may begin approaching the West Coast towards early next week.
Systems will work downstream across southern Canada and the U.S.
northern tier, albeit with limited precipitation. Energies feed
into an eastern/northeastern U.S. upper trough position to maintain
cooled precipittaion chances and cyclonic lake flow in the wake of
a main/moist lead system set to impact the Northeast this weekend.

Meanwhile, a developing weekend southern stream upper trough
digging into the Southwest offers uncertain ejection timing next
week, but should brings chances for showers and thunderstorms
across portions of Texas and the Gulf Coast states and Southeast.

...Guidance/Predictability Assessment...

The models show fairly good agreement with the deep, slow-moving
trough over the northeastern Pacific, extending toward the West
Coast, with anomalous riding downstream over much of the western
and central U.S.. The models also seem to have decent agreement on
the trough over eastern U.S. Although the broad pattern is
relatively consistent, differences remain with the amplitude and
phase of individual shortwaves, especially out from the Southwest.

Favor a composite of the best clustered ECMWF/Canadian
models/ensembles and machine learning guidance that does not
support the more progressive/deeper system solution of recent GFS
and to a lesser extent GEFS runs that do at least show a discounted
potential for much more substantial rainfall amounts over the
south-southeast.

...Weather/Hazards Highlights...

Persistent cyclonic flow and frontal boundaries affecting the
northeastern Pacific will maintain an active weather pattern across
the Pacific Northwest. Expect rain across Oregon and Washington
coastal areas and lower elevations, with possible high-elevation
snow through the weekend. By early next week, a deeper eastern
Pacific trough will increase onshore moisture transport and the
potential of a more organized atmospheric river event. This may
support showers expanding into California, while stronger winds
become possible along portions of the West Coast.

Farther south, a main weekend southern stream upper trough/surface
system should eject eastward across the southern tier and interact
with Gulf and eventually Atlantic moisture, bringing scattered
showers and thunderstorms across parts of Texas and the Gulf
Coast/Southeast.

Across eastern U.S., renewed shortwave energy dropping
southeastward from the northern Plains may reinforced troughing,
which will support additional periods of showers across the Great
Lakes into the Northeast through the weekend. Additionally, a
potential development of a coastal low may bring additional showers
and gusty winds along the Mid-Atantic and Northeast coast,
although the timing and track remains uncertain. Father north,
cold-air advection behind the frontal passages may support periods
of lake effect downwind of the Great Lakes into next week.

Oudit/Schichtel


Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards outlook chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php

WPC medium range 500mb heights, surface systems, weather grids,
quantitative precipitation forecast, excessive rainfall outlook,
winter weather outlook probabilities, heat indices and Key Messages
are at:

https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif
https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html
https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml
https://www.wpc.ncep.noaa.gov/#page=ero
https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4
https://www.wpc.ncep.noaa.gov/heat_index.shtml
https://www.wpc.ncep.noaa.gov/#page=ovw

Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EST Wed Nov 4 2026

Valid 00Z Thu 05 Nov 2026 - 00Z Thu 12 Nov 2026

Easterly trades are expected to prevail across the islands
through the period. NHC continues to highlight the likelihood that
a broad area of low pressure centered over the western portion of
the East Pacific basin will become better organized, with a
tropical depression expected to develop as the system moves west
to west-northwestward into the Central Pacific basin later this
week. This system is forecast to remain well south of the islands.
However, a broad moisture shield to its north is expected to
reach at least as far north as the Big Island Friday and Saturday,
enhancing shower development, before drier air spreads back
across the islands from the northeast early next week.

Pereira

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
307 PM EST Wed Nov 4 2026
Day 1
Valid 16Z Wed Nov 04 2026 - 12Z Thu Nov 05 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR A PORTION OF
SOUTHEAST FLORIDA AS WELL AS FOR PORTIONS OF THE OHIO AND TENNESSEE
VALLEYS AND SOUTHERN APPALACHIANS...

16Z Excessive Rainfall Discussion...
Composite radar clearly depicted a slow-moving cold front extending
north to south across the Ohio and the Tennessee Valleys with
showers and some embedded thunderstorms in the warm air ahead of
the front. 12Z soundings showed the pre-frontal airmass
characterized by precipitable water values of 1.75+ inches feeding
into the Tennessee Valley from the south with sufficient
instability to support local downpours but the dry antecedent
conditions should mitigate the overall flash flood threat to the
point where a Marginal risk remains appropriate.

In southeast Florida...the on-shore flow regime will continue to
support localized downpours in and near the urban corridor into the
late afternoon or early evening.

Bann

Previous Excessive Rainfall Discussion...

...Tennessee and Ohio Valleys and Southern Appalachians...

A slow-moving cold front moving across the lower Ohio and
Tennessee Valleys this morning will continue to push east into the
upper valleys and southern Appalachians today. Training showers
with a few embedded thunderstorms are expected to persist through
the day. Those thunderstorms could produce rainfall rates of 1-1.5
inches at times, which could cause an isolated flash flooding
threat. This is mostly due to the influx of abundant Gulf moisture
with PWATs to 1.75 inches. Working against significant flooding are
the very dry antecedent soil conditions from an entire second half
of October with very little to no rain. Instability will also limit
rainfall rates, as values in most of the Marginal Risk area
struggle to get even to 1,000 J/kg. The Southern Appalachians could
have a bit higher flash flooding risk due to the terrain influences
and added upslope wringing out additional rainfall on those local
areas.

...Southeast Florida...

A final day of continued onshore light easterly flow with an
abundance of tropical moisture will once again promote any storms
having a heavy rainfall and consequent flash flooding risk today.
As has been the case the past few days, the storms will form over
the straits between the northwest Bahamas and Florida, then drift
east towards the urban corridor between West Palm Beach and Miami.
This area has been in this pattern for over a week, so the soils in
this normally flood-resistant area are fully saturated. Thus, any
new rainfall will immediately convert to runoff. While storm
coverage is expected to be much more isolated than previous days,
the potential for flash flooding development remains high enough to
keep the inherited Marginal Risk ongoing with few changes.
Fortunately by tomorrow, developing northerly flow will advect
significantly drier air into south Florida, allowing the area to
begin a much drier period.

Wegman


Day 1 threat area: www.wpc.ncep.noaa.gov/qpf/94epoints.txt

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
307 PM EST Wed Nov 4 2026
Day 2
Valid 12Z Thu Nov 05 2026 - 12Z Fri Nov 06 2026

The probability of rainfall exceeding flash flood guidance is less
than five percent.

Bann


Day 2 threat area: www.wpc.ncep.noaa.gov/qpf/98epoints.txt

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
307 PM EST Wed Nov 4 2026
Day 3
Valid 12Z Fri Nov 06 2026 - 12Z Sat Nov 07 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR SOUTHERN NEW
ENGLAND...

2030Z Update...
Mainlined the Marginal risk area for a portion of southeast New
England on Friday. Numerical guidance continues to depict a stripe
of 1.5 to 2.5+ inches of rainfall along and to the east of a cold
front making its way across the region. Even though there was a bit
of an eastward shift in the rainfall axis...it was not enough to
preclude westward shifts with time so the outlook area largely
remained unchanged from the overnight issuance.

Bann

Previous Excessive Rainfall Discussion...

Only minor tweaks were made to the inherited Marginal Risk area for
southern New England, NYC and Long Island on Friday. There remains
considerable uncertainty as to where the western edge of the rain
shield will be, with the best forecast looking like it will be
right over NYC and the lower Hudson Valley. A wave may try to push
the plume of heaviest rain west across NYC Friday afternoon,
before the rain shield wraps up and pushes everything east out to
sea. There's more certainty that eastern Long Island through
southern New England will be stuck in the axis of heaviest rainfall
for much of the period. Despite a prolonged period of dry weather
going into this event, as well as limited instability generally
sub-500 J/kg, PWATs around 1.5 inches, urban, and upslope
enhancement should work to cancel those out. This will result in
isolated instances of flash flooding in urban and poor-drainage
areas. Any additional eastward shifts in the plume would remove the
NYC metro from the Marginal with future updates.

Wegman

Day 3 threat area: www.wpc.ncep.noaa.gov/qpf/99epoints.txt

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
307 PM EST Wed Nov 4 2026
Day 4 and Day 5

Valid 12Z Sat Nov 07 2026 - 12Z Mon Nov 09 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF SOUTHERN TEXAS THIS WEEKEND...

Model guidance is beginning to converge on a synoptic evolution
that would favor areas of heavy rain over southern TX this weekend.
A mid to upper low is forecast to dive southeast out of AZ and
into northern MX late Friday, and then progress eastward towards
West TX by Sunday. This feature will provide ample ascent for
rainfall, with a strong upper level jet providing additional lift.
Anomalous moisture will advect northward ahead of this system, and
while PWs will likely not be as high as recent events, it is still
forecast to exceed the climatological 90th percentile. In the low
levels we should have east to northeasterly flow, which will aid in
isentropic ascent over the region, but should also act as a
stabilizing factor. Thus the degree of instability, which will
impact rainfall rates and the flash flood potential, remains a
question.

What was large model spread in the evolution of the closed low has
shrunk with the 12z suite of models. The AIFS has generally been
the most persistent model showing the heavy rainfall threat, but
at 12z the ECMWF/GFS/AIGFS all trended in this direction as well.
So while some additional model fluctuations can be expected, there
is enough agreement to go with a Marginal risk at this time.
If/where sufficient destabilization is able to occur to drive
higher rainfall rates, a future Slight risk upgrade may be
necessary. Best chances for this at the moment appear to be along
the south TX coast where instability advecting in off the water
and coastal convergence could focus higher rainfall magnitudes.

Chenard

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
307 PM EST Wed Nov 4 2026
Day 4 and Day 5

Valid 12Z Sat Nov 07 2026 - 12Z Mon Nov 09 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF SOUTHERN TEXAS THIS WEEKEND...

Model guidance is beginning to converge on a synoptic evolution
that would favor areas of heavy rain over southern TX this weekend.
A mid to upper low is forecast to dive southeast out of AZ and
into northern MX late Friday, and then progress eastward towards
West TX by Sunday. This feature will provide ample ascent for
rainfall, with a strong upper level jet providing additional lift.
Anomalous moisture will advect northward ahead of this system, and
while PWs will likely not be as high as recent events, it is still
forecast to exceed the climatological 90th percentile. In the low
levels we should have east to northeasterly flow, which will aid in
isentropic ascent over the region, but should also act as a
stabilizing factor. Thus the degree of instability, which will
impact rainfall rates and the flash flood potential, remains a
question.

What was large model spread in the evolution of the closed low has
shrunk with the 12z suite of models. The AIFS has generally been
the most persistent model showing the heavy rainfall threat, but
at 12z the ECMWF/GFS/AIGFS all trended in this direction as well.
So while some additional model fluctuations can be expected, there
is enough agreement to go with a Marginal risk at this time.
If/where sufficient destabilization is able to occur to drive
higher rainfall rates, a future Slight risk upgrade may be
necessary. Best chances for this at the moment appear to be along
the south TX coast where instability advecting in off the water
and coastal convergence could focus higher rainfall magnitudes.

Chenard

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
236 PM EST Wed Nov 4 2026

Valid 12Z Wed Nov 04 2026 - 12Z Sat Nov 07 2026

...Central Rockies...
Day 1...

A closed 500mb low tracking east through UT will reach the CO
Rockies this afternoon, bringing an influx of anomalous moisture
to the Central Rockies. ECMWF guidance shows PWs above the 90th
climatological percentile traversing the Central Rockies tonight.
The region also lies beneath the divergent left-exit region of a
~110kt 250mb jet streak that will foster enhanced upper-level
divergence. In addition, 700mb winds in lee of the CO Rockies will
gradually increase out of the east this evening as the 700mb low
tracks over central CO, resulting in enhanced upslope flow along
the Front Range. The heaviest snowfall is likely to occur as the
700mb low passes through early Wednesday evening and an inverted
700mb trough axis moves overhead tonight. Snow is forecast to taper
off by Thursday morning.

Guidance over the past 12-24 hours has come into better agreement
on a period of heavy snowfall between 00-06Z Thursday over the
Sawatch and Mosquito Mountains at/above 11,000ft. Snowfall rates
>1"/hr in the Sawatch/Mosquito ranges and into the higher CO Front
Range peaks are likely (>70% per the 12Z REFS). Chances for >2"/hr
snowfall rates have also increased with the 12Z REFS now showing
moderate- to-high chances (50-70%) in Sawatch/Mosquito Ranges. The
closed low will open up into a positively-tilted upper trough early
Thursday morning and snowfall rapidly concludes by sunrise
Thursday. The PPP shows high chances (>70%) for snowfall totals >8"
in the CO mountain ranges above 11,000ft. The peaks of the Sawatch
and Mosquito Ranges do contain moderate-to-high chances (50-70%)
for snowfall totals >12". The WSSI highlights Minor Impacts as low
as 9,000ft that could result in locally hazardous travel conditions
along some nearby highways, including US-285. There is Moderate
Impact potential (disruptions to daily life; possible closures) as
low as 10,000ft, including US-24 from Leadville to Riverside, CO.


The probability of significant ice across the CONUS is less than 10
percent.


Mullinax

Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
300 PM EST Wed Nov 4 2026

Valid 12Z Sat Nov 07 2026 - 12Z Wed Nov 11 2026


...Overview...

The weather pattern will remain active for the Pacific Northwest as
a series of amplified northeastern Pacific upper troughs and
surface systems move toward the region, bringing windy periods with
heavy rain and high elevation snow. A potential atmospheric river
event may begin approaching the West Coast towards early next week.
Systems will work downstream across southern Canada and the U.S.
northern tier, albeit with limited precipitation. Energies feed
into an eastern/northeastern U.S. upper trough position to maintain
cooled precipittaion chances and cyclonic lake flow in the wake of
a main/moist lead system set to impact the Northeast this weekend.

Meanwhile, a developing weekend southern stream upper trough
digging into the Southwest offers uncertain ejection timing next
week, but should brings chances for showers and thunderstorms
across portions of Texas and the Gulf Coast states and Southeast.

...Guidance/Predictability Assessment...

The models show fairly good agreement with the deep, slow-moving
trough over the northeastern Pacific, extending toward the West
Coast, with anomalous riding downstream over much of the western
and central U.S.. The models also seem to have decent agreement on
the trough over eastern U.S. Although the broad pattern is
relatively consistent, differences remain with the amplitude and
phase of individual shortwaves, especially out from the Southwest.

Favor a composite of the best clustered ECMWF/Canadian
models/ensembles and machine learning guidance that does not
support the more progressive/deeper system solution of recent GFS
and to a lesser extent GEFS runs that do at least show a discounted
potential for much more substantial rainfall amounts over the
south-southeast.

...Weather/Hazards Highlights...

Persistent cyclonic flow and frontal boundaries affecting the
northeastern Pacific will maintain an active weather pattern across
the Pacific Northwest. Expect rain across Oregon and Washington
coastal areas and lower elevations, with possible high-elevation
snow through the weekend. By early next week, a deeper eastern
Pacific trough will increase onshore moisture transport and the
potential of a more organized atmospheric river event. This may
support showers expanding into California, while stronger winds
become possible along portions of the West Coast.

Farther south, a main weekend southern stream upper trough/surface
system should eject eastward across the southern tier and interact
with Gulf and eventually Atlantic moisture, bringing scattered
showers and thunderstorms across parts of Texas and the Gulf
Coast/Southeast.

Across eastern U.S., renewed shortwave energy dropping
southeastward from the northern Plains may reinforced troughing,
which will support additional periods of showers across the Great
Lakes into the Northeast through the weekend. Additionally, a
potential development of a coastal low may bring additional showers
and gusty winds along the Mid-Atantic and Northeast coast,
although the timing and track remains uncertain. Father north,
cold-air advection behind the frontal passages may support periods
of lake effect downwind of the Great Lakes into next week.

Oudit/Schichtel


Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards outlook chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php

WPC medium range 500mb heights, surface systems, weather grids,
quantitative precipitation forecast, excessive rainfall outlook,
winter weather outlook probabilities, heat indices and Key Messages
are at:

https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif
https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html
https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml
https://www.wpc.ncep.noaa.gov/#page=ero
https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4
https://www.wpc.ncep.noaa.gov/heat_index.shtml
https://www.wpc.ncep.noaa.gov/#page=ovw