916
FXUS06 KWBC 241943
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Mon June 24 2024

6-10 DAY OUTLOOK FOR JUN 30 - JUL 04, 2024

Near-zonal mid-level flow is predicted by the ensemble mean models during the
6-10 day period across the Contiguous U.S. (CONUS). Todays manual height blend
is a near-equal weighting of the three ensemble mean solutions (GEFS, ECENS and
Canadian (CMCE)). Above-normal 500-hPa heights are depicted over most of the
CONUS and Alaska. Over the south-central and southeastern CONUS, 594-dm heights
are forecast, with height departures exceeding +60 meters from the Lower and
Middle Mississippi Valley to the East Coast from southern New England southward
through the Carolinas. Weak troughing is predicted from the Pacific Northwest
into the far northern Rockies, and heights are forecast to be close to normal
across the Four Corners region on the manual height blend. In Alaska, a +150
meter height anomaly center is indicated on the manual height blend just south
of the Aleutians, with weak positive mid-level height anomalies across the
Mainland and Southeast Alaska. Farther south, modestly below-normal 500-hPa
heights are indicated over Hawaii.

Positive 500-hPa height anomalies lead to likely above-normal temperatures in
the forecast across most of the central and southern thirds of the CONUS.
Above-normal temperature chances exceed 70% from eastern sections of the
Southern Plains to the Carolinas. Near to below-normal temperatures are favored
for approximately the northern third of the CONUS, due to several factors. One
factor is the anticipated intrusions of relatively cool Canadian air near the
border, and the other is related to increased cloudiness and precipitation
helping to keep temperatures down. There are increased chances for above-normal
temperatures for central and eastern Mainland Alaska and much of Southeast
Alaska due to a predicted mid-level ridge and positive height anomalies. A
slight tilt towards below-normal temperatures is favored along the west coast
of Alaska due to the proximity of relatively cool sea-surface temperatures
(SSTs). In Hawaii, dynamical model guidance favors below-normal temperatures
state-wide.

Above-normal precipitation is favored for most of the northern and western
halves of the Lower 48 states. In the north, a mid-level trough and embedded
short-wave energy are primarily responsible for the relatively wet
precipitation outlook. Across the vicinity of the Four Corners region,
above-normal precipitation chances are favored, as supported by many of the
objective precipitation tools. Although an anomalously wet pattern is favored
across the Southwest, this is still not the classic summer monsoon setup, which
typically features the subtropical ridge anchored over the Four Corners region.
Below-normal precipitation chances are favored over the northern half of
California and much of Nevada, with this area being sufficiently distant from
precipitation-producing systems anticipated to its north and southeast.
Below-normal rainfall is also favored across much of the southern Mid-Atlantic
region and south-central CONUS, with the former region undergoing rapid
deterioration of soil moisture conditions due to recent heat waves, very high
rates of evapotranspiration, and lack of precipitation in the past few weeks.
For Alaska and Hawaii, above-normal precipitation chances are favored due to
fairly good agreement among the precipitation tools.

The official 6-10 day 500-hPa height blend consists of 33% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 34% of Today`s 0z European Ensemble Mean
centered on Day 8, and 33% of Today`s 0z Canadian Ensemble Mean centered on Day
8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: Above Average, 4 out of 5, due to
generally good agreement among the 500-hPa height forecasts and surface
temperature tools, offset by some differences in the precipitation guidance.

8-14 DAY OUTLOOK FOR JUL 02 - 08 2024

Near-zonal mid-level flow is expected to continue throughout much of week-2.
The manual height blend, which is almost equally weighted between the three
ensemble means, depicts positive height anomalies of at least +30 meters across
most of the central and eastern CONUS and central West Coast states, with
500-hPa heights close to average elsewhere (which includes a large portion of
the western CONUS). According to uncalibrated height guidance for the week-2
period as a whole, the ECENS and CMCE predict 594-dm heights over the Southeast
and parts of the south-central CONUS, while the GEFS is somewhat less bullish
(i.e., slightly less warm), with the highest plotted height contour of 588 dm.
In the vicinity of Alaska, a +180 meter height anomaly center is indicated on
the manual height blend just south of the Aleutians, with weak positive height
anomalies forecast across the Mainland and Southeast. For Hawaii, mid-level
heights are predicted to be close to normal during week-2.

Above-normal temperatures continue to be likely across most of the CONUS in
week-2 under positive 500-hPa height anomalies. Compared to the earlier 6-10
day temperature outlook, above-normal temperatures are favored to overspread
most of the Great Lakes region and Northeast during week-2. Odds favoring
above-normal temperatures exceed 70% for most of the southeastern quarter of
the CONUS. Odds favor below-normal temperatures in the Pacific Northwest, and
northern portions of the Intermountain region and Rockies due to the proximity
of a weak mid-level trough. Near to slightly below-normal temperatures are
favored over parts of the southern Four Corners region, due to an anticipated
increase in cloud cover and precipitation. In Alaska, below-normal temperature
chances are enhanced over western portions of the state and most of Southeast
Alaska, and above-normal temperature chances are slightly enhanced over
portions of the eastern Mainland. This is consistent with the auto-temperature
tool, and relatively cool SSTs in the adjacent Bering Sea. With a slight
increase in amplitude predicted in the mid-level ridge over the Aleutians
during week-2, downstream 500-hPa heights are expected to lower across western
portions of Alaska, resulting in cooler temperatures. For most of Hawaii, a
compromise between the ERF-CON and automated temperature tools favors a slight
tilt towards below-normal temperatures during week-2.

The week-2 precipitation outlook is similar to the earlier 6-10 day
precipitation outlook, with areas of favored above-normal precipitation
depicted over the Northwest (albeit slightly), the Midwest, and the Four
Corners region, with similar reasoning as the earlier period. An expansion of
below-normal precipitation chances is indicated across the Southeast, Gulf
Coast states, and northeastern Texas, as well as over a larger portion of the
western CONUS. This is generally consistent with the precipitation tools.
Auto-precipitation guidance favors above-normal precipitation for most of
Alaska and Hawaii during week-2.

The official 8-14 day 500-hPa height blend consists of: 35% of Today`s 0z GFS
Ensemble Mean centered on Day 11, 35% 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: Average, 3 out of 5, due to good
agreement among the temperature tools offset by only fair agreement among the
precipitation tools.

FORECASTER: Anthony A

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
July 18.


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:
20050629 - 20060619 - 19530618 - 20040607 - 19940614


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:
20050629 - 19530618 - 19940613 - 20060618 - 20040607


6-10 DAY OUTLOOK TABLE
Outlook for Jun 30 - Jul 04, 2024

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



8-14 DAY OUTLOOK TABLE
Outlook for Jul 02 - 08 2024

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

                           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.

$$