444
FXUS06 KWBC 222002
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EST Fri November 22 2024

6-10 DAY OUTLOOK FOR NOV 28 - DEC 02, 2024

During the 6-10 day period models remain in fairly good agreement relative to
yesterday on an amplified and progressive mid-level height pattern across North
America and the surrounding regions. Strong positive 500-hPa height anomalies
are forecast to be centered along the Pacific Northwest coast bringing stronger
positive mid-level anomalies to much of the West Coast relative to yesterday.
These anomalies are stronger and have a more distinct center with greater
separation from positive 500-hPa height anomalies forecast to be centered
across eastern Siberia. Positive mid-level height anomalies remain forecast for
much of Alaska between these two positive height anomaly centers. Meanwhile, a
fast moving mid-level trough and associated negative 500-hPa height anomalies
are forecast to progress from the Plains through the eastern contiguous U.S.
(CONUS) during the 6-10 day period.

During the 6-10 day period, below-normal temperature chances are strongly
favored across much of the eastern CONUS beneath strong negative mid-level
height anomalies. The forecast for the western CONUS is more complicated.
Above-normal mid-level heights are beginning to build into the region during
the 6-10 day period and this may drive a warming trend through the period. Many
of the tools are forecasting lower probabilities for below-normal temperatures
relative to yesterday, with some leaning towards above. As such, a broad area
of near-normal is now forecast for the 6-10 day period for much of the western
CONUS. In Alaska, tools are in good agreement for below-normal temperatures
across much of the state. There are more mixed signals in Southeast Alaska
where near-normal temperatures are forecast. In Hawaii, above-normal
temperatures remain likely across much of the state.

Strong mid-level ridging along and off the West Coast will limit onshore flow
and Pacific moisture and bring below-normal precipitation chances to much of
the West Coast, Southwest, and Southern Plains. Above-normal precipitation
remains forecast along the East Coast, as mid-level troughing and associated
frontal system moves through the region. Behind this system a general drying
trend is forecast and near-normal precipitation is favored across much of the
central CONUS. Some above-normal remains favored in the Northern Plains
consistent with the dynamical and statistical tools. In Alaska, the best
chances for above-normal precipitation are along the south-central and
southeast Mainland, while below-normal precipitation is favored in western
Mainland. Near normal precipitation is favored in Southeast Alaska with
mid-level high pressure to the West. In Hawaii, below-normal precipitation is
favored consistent with reforecast and bias-corrected tools.

The official 6-10 day 500-hPa height blend consists of 10% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 20% of Today`s 6z GFS Ensemble Mean centered
on Day 8, 40% of Today`s 0z European Ensemble Mean centered on Day 8, and 30%
of Today`s 0z Canadian Ensemble Mean centered on Day 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: Average, 3 out of 5. Good
agreement among the dynamical and statistical tools is offset by a progressive
and shifting pattern.

8-14 DAY OUTLOOK FOR NOV 30 - DEC 06, 2024

The week-2 height forecast is quite similar to the 6-10 day period with a
positive mid-level height anomaly center off the Pacific Northwest coast with
positive anomalies stretching northwest through Alaska to another height center
across eastern Siberia. Strong negative mid-level height anomalies remain
forecast for much of the eastern CONUS.

Below-normal temperatures are likely across much of the eastern CONUS during
the week-2 period consistent with prior forecasts and dynamical and statistical
guidance. The big change is across the West, with a rapid warm up forecast
during the week-2 period. Daily mean temperature anomaly forecasts from the
GEFS and ECENS become warmer than normal by around day 10 or 11 across much of
the western CONUS. This would be consistent with the big visual change in the
week-2 forecast across the western CONUS. In Alaska, below-normal temperatures
are generally favored across much of Mainland Alaska. In Southeast Alaska,
near-normal temperatures are favored with a little stronger onshore flow
developing overtop of a mid-level ridge. In Hawaii, above-normal temperatures
are strongly favored with all guidance being strongly in agreement.

The precipitation outlook for the CONUS is more confident relative to yesterday
with better agreement between the GEFS and ECENS. Below-normal precipitation is
favored for much of the West Coast, Great Basin, and Southwest with mid-level
ridging upstream limiting onshore flow. Above-normal precipitation remains
favored for the Northern Rockies and Northern Plains. Further east, across the
Central Mississippi east towards the Appalachians through the Northeast an area
of below-normal precipitation is favored. There is good agreement among the
dynamical tools for dry conditions in this area. Above-normal is favored for
portions of Florida with a frontal system still possibly moving through the
region at the onset of week-2. In Alaska, below-normal precipitation is favored
for the western portions of the state with above-normal precipitation favored
for southeastern portions of Mainland Alaska and Southeast Alaska. In Hawaii,
near-normal precipitation is generally favored for much of the state excluding
the Big Island where below-normal precipitation is forecast.

The official 8-14 day 500-hPa height blend consists of: 10% of Today`s 0z GFS
Ensemble Mean centered on Day 11, 20% of Today`s 6z GFS Ensemble Mean centered
on Day 11, 40% of Today`s 0z European Ensemble Mean centered on Day 11, and 30%
of Today`s 0z Canadian Ensemble Mean centered on Day 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Below-Average, 2 out of 5, with
divergent solutions among the model guidance for temperature and precipitation
reducing confidence.

FORECASTER: Ryan Bolt

Notes:


Automated forecasts are issued on Saturday and Sunday. Occasionally manual
intervention is necessary to address quality control and consistency issues. In
these cases, forecasts are manually drawn but a full discussion is not issued.


The notation for the categorical forecast indicated on the maps is the same as
that in the tables: A-above   N-near normal   B-below


The temperature map shows regions with > 33% chance of being warmer (orange,
"A"), colder (blue, "B"), or close to (unshaded, "N"). Historical average
values for the calendar period of the forecast (dashes, "f").  Labels on the
shaded lines give the probability (> 33%) of the more likely category (B or A).
 Probability of N is always < 40%.


The precipitation map shows regions with > 33% chance of being wetter (green,
"A"), drier (tan, "B"), or close to (unshaded, "n"). Historical median values
for the calendar period of the forecast (dashes, "inches").  Labels on the
shaded lines give the probability (> 33%) of the more likely category (B or A).
 Probability of N is always < 40%.


In the southwest and other climatologically dry regions - there will be a
greater than 33.3% chance of no precipitation and occasionally even a normal
(i.e. Median) value of zero - especially during the dry seasons.  In such cases
a forecast of near normal is effectively a forecast of little or no
precipitation.


The climate prediction center uses 1991-2020 base period means as reference in
the climate outlooks.

The next set of long-lead monthly and seasonal outlooks will be released on
December 19.


Analogs to the 5 day mean observed pattern centered 3 days ago (D-3)
for the region from 20N to 70N latitude and 175E to 60W longitude
include the 5 day periods centered on the following dates:
19631112 - 19731128 - 19961119 - 19611125 - 19731113


Analogs to the 7 day mean observed pattern centered 4 days ago (D-4)
for the region from 20N to 70N latitude and 175E to 60W longitude
include the 7 day periods centered on the following dates:
19631112 - 19611126 - 19961119 - 19731112 - 19661201


6-10 DAY OUTLOOK TABLE
Outlook for Nov 28 - Dec 02, 2024

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    B     OREGON      N    B     NRN CALIF   N    B
SRN CALIF   N    B     IDAHO       B    B     NEVADA      N    B
W MONTANA   B    N     E MONTANA   B    A     WYOMING     B    N
UTAH        N    B     ARIZONA     N    B     COLORADO    B    N
NEW MEXICO  N    N     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    B    N     KANSAS      B    N     OKLAHOMA    B    N
N TEXAS     B    B     S TEXAS     B    N     W TEXAS     B    B
MINNESOTA   B    A     IOWA        B    N     MISSOURI    B    N
ARKANSAS    B    N     LOUISIANA   B    N     WISCONSIN   B    N
ILLINOIS    B    N     MISSISSIPPI B    N     MICHIGAN    B    A
INDIANA     B    N     OHIO        B    A     KENTUCKY    B    N
TENNESSEE   B    N     ALABAMA     B    A     NEW YORK    B    A
VERMONT     B    N     NEW HAMP    B    A     MAINE       B    N
MASS        B    A     CONN        B    A     RHODE IS    B    A
PENN        B    A     NEW JERSEY  B    A     W VIRGINIA  B    A
MARYLAND    B    A     DELAWARE    B    A     VIRGINIA    B    A
N CAROLINA  B    A     S CAROLINA  B    A     GEORGIA     B    A
FL PNHDL    B    A     FL PENIN    N    A     AK N SLOPE  B    N
AK ALEUTIAN N    B     AK WESTERN  B    B     AK INT BSN  B    N
AK S INT    B    A     AK SO COAST N    A     AK PNHDL    N    N



8-14 DAY OUTLOOK TABLE
Outlook for Nov 30 - Dec 06, 2024

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    N     OREGON      N    B     NRN CALIF   A    B
SRN CALIF   A    B     IDAHO       N    B     NEVADA      N    B
W MONTANA   N    A     E MONTANA   N    A     WYOMING     N    A
UTAH        N    B     ARIZONA     A    B     COLORADO    N    N
NEW MEXICO  A    B     N DAKOTA    B    A     S DAKOTA    N    A
NEBRASKA    N    N     KANSAS      N    N     OKLAHOMA    N    N
N TEXAS     N    N     S TEXAS     N    A     W TEXAS     N    B
MINNESOTA   B    N     IOWA        B    N     MISSOURI    B    N
ARKANSAS    B    B     LOUISIANA   B    N     WISCONSIN   B    N
ILLINOIS    B    B     MISSISSIPPI B    N     MICHIGAN    B    N
INDIANA     B    B     OHIO        B    B     KENTUCKY    B    B
TENNESSEE   B    B     ALABAMA     B    N     NEW YORK    B    N
VERMONT     B    B     NEW HAMP    B    B     MAINE       B    B
MASS        B    B     CONN        B    B     RHODE IS    B    N
PENN        B    N     NEW JERSEY  B    N     W VIRGINIA  B    N
MARYLAND    B    N     DELAWARE    B    N     VIRGINIA    B    N
N CAROLINA  B    N     S CAROLINA  B    N     GEORGIA     B    N
FL PNHDL    B    N     FL PENIN    B    A     AK N SLOPE  N    N
AK ALEUTIAN N    B     AK WESTERN  B    B     AK INT BSN  B    N
AK S INT    B    A     AK SO COAST N    A     AK PNHDL    N    A

                           LEGEND
TEMPS WITH RESPECT TO NORMAL     PCPN WITH RESPECT TO MEDIAN
A - ABOVE   N  - NEAR NORMAL     A - ABOVE   N - NEAR MEDIAN
B - BELOW                        B - BELOW

THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE.

FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS
PMDMRD.

$$