Prognostic Meteorological Discussion
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FXUS06 KWBC 041902
PMDMRD
Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks
NWS Climate Prediction Center College Park, MD
300 PM EDT Thu July 04 2024

6-10 DAY OUTLOOK FOR JUL 10 - 14 2024

The GEFS, ECENS, and CMCE model solutions are in good agreement with a high
amplitude 500-hPa trough over Mainland Alaska while a downstream mid-level
ridge shifts east across the western contiguous U.S. (CONUS). This amplified
longwave pattern yields increased chances of below (above) normal temperatures
for Alaska (western and north-central CONUS). These ensemble means are
consistent that a mid-level trough, initially over the Mississippi Valley,
weakens by day 8. Although near normal temperatures are favored across parts of
the Midwest, warmer-than-normal temperatures are anticipated by day 10. The
expectation of enhanced cloudiness and rainfall favor below-normal temperatures
for much of the south-central CONUS. Above-normal temperatures are more likely
closer to the East Coast due to little if any cold air advection east of the
Appalachians.

As of 11am EDT on July 4, the National Hurricane Center (NHC) states that
Hurricane Beryl will cross the Yucatan Peninsula and reemerge over the
southwestern Gulf of Mexico. Beryl is expected to make a final landfall along
the western Gulf Coast prior to this outlook period. By day 6, the GEFS and
ECENS indicate that the remnant low, associated with Beryl, could be anywhere
from the Rio Grande Valley to eastern Texas or the lower Mississippi Valley.
There is another following tropical wave that NHC states has a 20 percent
chance of becoming a tropical cyclone (TC) during the next week. The majority
of ensemble members have this tropical wave or TC tracking towards northeastern
Mexico or the lower Rio Grande Valley on days 6 and 7.

The combination of the remnant low, associated with Beryl, and the following
tropical wave or TC support enhanced above-normal precipitation probabilities
across the western Gulf Coast, Rio Grande Valley, and southern Great Plains.
The increased chances of above-normal precipitation probabilities across the
eastern CONUS are related to the amplified trough initially over the
Mississippi Valley. These above-normal precipitation probabilities are further
enhanced for the Mid-Atlantic and Northeast as a stationary front provides a
focus for diurnal convection. For the second consecutive day, precipitation
tools trended wetter across the Southwest as the 500-hPa ridge axis lifts
northward to the Four Corners region. A highly amplified ridge favors
below-normal precipitation for much of the northern half of the western CONUS
along with the northern to central Great Plains and upper Mississippi Valley.
Troughing across Alaska favors increased above-normal precipitation
probabilities across the state.

Based on the GEFS and ECENS, above-normal temperatures are favored for Hawaii.
Due to weak and conflicting signals among the precipitation tools, near normal
precipitation is forecast.

The official 6-10 day 500-hPa height blend consists of 35% of Today`s 0z GFS
Ensemble Mean centered on Day 8, 40% of Today`s 0z European Ensemble Mean
centered on Day 8, and 25% of Today`s 0z Canadian Ensemble Mean centered on Day
8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: Forecast confidence: Above
average, 4 out of 5, due to a high amplitude longwave pattern over Alaska and
the western CONUS and good agreement among the temperature and precipitation
tools.

8-14 DAY OUTLOOK FOR JUL 12 - 18 2024

The GEFS, ECENS, and CMCE remain consistent that the high amplitude ridge over
the western CONUS expands eastward during mid-July. The manual 500-hPa height
blend depicts +30 meter anomaly departures for much of the lower 48 states,
which is substantial for the summer. 500-hPa height anomalies increase to more
than 60 meters across the northern third of the CONUS. This expansive and
anomalous 500-hPa ridge favors above-normal temperatures for nearly all of the
lower 48 states except for parts of Texas where enhanced cloudiness and
rainfall may linger. The largest probabilities (more than 80 percent) of
above-normal temperatures are forecast across the northern Rockies and northern
Great Plains where 7-day temperatures are likely to average more than +10
degrees F. A persistent trough favors a continuation of cooler-than-normal
temperatures across Alaska.

The week-2 precipitation outlook is based on continuity from previous days
along with the consolidation (skill-weighted combination of GEFS and ECMWF
reforecasts) and the analog tool derived from the 500-hPa height blend.
Enhanced low-level moisture coupled with a slight weakness in the subtropical
ridge are expected to result in scattered diurnal convection each day
throughout much of the eastern and south-central CONUS. The precipitation tools
depict a couple of maximum probability areas including the eastern Carolinas
and Texas. Model solutions depict a 500-hPa ridge axis over the Four Corners
which is a favorable location for an enhanced Monsoon. Precipitation tools have
trended wetter today across the Great Basin and central Rockies as the enhanced
Monsoon moisture is expected to spread northward. Anomalous mid-level ridging
favors below-normal precipitation from the Pacific Northwest east to the
northern and central Great Plains. Cyclonic flow and below-normal 500-hPa
heights support above-normal precipitation probabilities throughout Alaska.

Based on the GEFS and ECENS, above-normal temperatures are favored for Hawaii.
Due to weak and conflicting signals among the precipitation tools, near normal
precipitation is forecast.

The official 8-14 day 500-hPa height blend consists of: 35% of Today`s 0z GFS
Ensemble Mean centered on Day 11, 40% of Today`s 0z European Ensemble Mean
centered on Day 11, and 25% of Today`s 0z Canadian Ensemble Mean centered on
Day 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Forecast confidence: Above
average, 4 out of 5, due to good model agreement on the evolving longwave
pattern and good agreement between the dynamical and statistical tools.

FORECASTER: Brad Pugh

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 - 20060620 - 20040615 - 20070616 - 19790716


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:
20050628 - 20070616 - 20000623 - 20030627 - 20040615


6-10 DAY OUTLOOK TABLE
Outlook for Jul 10 - 14 2024

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



8-14 DAY OUTLOOK TABLE
Outlook for Jul 12 - 18 2024

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

$$