Valid Saturday, August 02, 2014 to Wednesday, August 13, 2014
Summary of Forecasts and Hazards
US Hazards Outlook
NWS Climate Prediction Center College Park MD
EDT July 30 2014Synopsis
: A stationary front is forecast to
slowly dissipate along the East Coast by early next week, while a cold front
progresses from the Midwest to the Northeast on Monday and Tuesday. An area of
upper-level high pressure is expected to remain centered over the northwestern
U.S. during the next week but a weak low pressure system is forecast to lift
north from the desert Southwest. A large area of upper-level low pressure is
expected to persist across the Gulf of Alaska. Hazards
Detailed Summary For Saturday August 02 - Wednesday August 06:
- Much above-normal temperatures for parts of the Pacific Northwest and
Northern Intermountain West, Sat-Tue, Aug 2-5.
- Heavy rain for the coastal areas of the southern mid-Atlantic and
Southeast, Sat-Sun, Aug 2-3.
- The possibility of flash flooding shifting north from the desert Southwest
to Colorado and Utah, Sat-Tue, Aug 2-5.
- Severe drought for parts of the Great Plains, Southwest, Pacific Northwest,
Great Basin, and California.
numerous thundershowers with locally heavy rainfall are expected across the
Southwest this weekend as monsoon moisture becomes enhanced. Flash flooding is
likely to remain the major hazard across this region until the flow becomes
more westerly. The 6z GFS model indicates that precipitable water values
increase to more than 1 inch across the desert Southwest on Saturday. In
addition to the flash flooding hazard, outflow from thunderstorms is capable of
causing blowing dust across southern Arizona. Early next week, the GFS and
ECMWF models indicate that a mid-level disturbance and enhanced moisture lift
north to the central Rockies which would likely increase the risk of heavy rain
and flash flooding across Colorado and Utah. Therefore, a broad area of
possible flash flooding is posted.
Enhanced low-level convergence along a stationary front coupled with
increasing moisture is expected to result in heavy rainfall across coastal
areas of the southern mid-Atlantic and Southeast on Saturday and Sunday.
An amplified ridge over the northwestern U.S. is likely to maintain much
above-normal temperatures through at least Tuesday across the interior Pacific
Northwest and northern intermountain West. Numerous wildfires continue to burn
across these areas along with California, Nevada, and Utah. Currently, the
largest wildfire with nearly 400,000 acres burned is located in southeast
Oregon. A few dry thunderstorms could ignite additional wildfires across the
northern Great Basin and Pacific Northwest.
The coverage of showers is expected to increase across southern Alaska by
early next week, but precipitation amounts are likely to remain below hazards
criteria. For Thursday August 07 -
Wednesday August 13:
Spread amongst the 0Z/6Z GFS ensemble members becomes
large across the northwestern conus during Week-2. A slight risk of
above-normal temperatures for parts of the Pacific Northwest on August 7 and 8
are posted on the Probabilistic Week-2 Hazards Outlook since a minority of
0Z/6Z GFS ensemble members maintain a strong upper-level ridge across this
The deterministic GFS and ECMWF models favor an intensifying area of low
pressure across the western Bering Sea early during Week-2. This low pressure
development should be monitored for potential wind/precipitation hazards across
the Aleutians. Meanwhile, the GFS model remains consistent with a tropical
system approaching Hawaii by August 7.
As of 2pm EDT on Wednesday, an area of low pressure is located near
10N/45W. Convection has decreased during the past 24 hours and the National
Hurricane Center states that there is a medium chance for tropical formation
during the next 48 hours.
Based on the latest Drought Monitor valid on July 22, severe to exceptional
drought continued to decrease and now covers 23.9 percent of the continental
Forecaster: Brad Pugh
Click here to see a display of the GFS Ensemble Forecasts
Please consult local NWS Forecast Offices for short range forecasts and region-specific information.