US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
455 PM EDT Fri Jul 24 2020
 
Valid Monday July 27 2020 - Friday July 31 2020
 
Hazards:
- Heavy rain possible from Arkansas eastward across the interior Southeast into the Carolinas and 
southern Virginia, Wed-Fri, Jul 29-Jul 31.
- Heavy rain across portions of the central High Plains to central/southern Rockies, as well as 
along the central and eastern Gulf Coast, Mon-Tue, Jul 27-Jul 28.
- Flooding possible across portions of the central and southern Plains.
- Flooding occurring or imminent across portions of the northern and central Plains.
- Excessive heat across portions of the the Mid-Atlantic region, Mon-Tue, Jul 27-Jul 28.
- Much above normal temperatures across portions of the Pacific Northwest, Mon-Tue, Jul 27-Jul 28.
- Much above normal temperatures across portions of the northern Mid-Atlantic into southern New 
England, Mon, Jul 27.
- Heavy rain across portions of the Brooks Range and interior southeastern Alaska, Mon-Tue, Jul 
27-Jul 28.
 
Detailed Summary:

Tropical Storm Hanna, currently moving generally westward toward southern Texas, is forecast to 
dissipate over the mountainous terrain of northern Mexico by next Monday according to the latest 
from the National Hurricane Center.  The threat of heavy rain should be diminishing on Monday 
across southern Texas.  However, lingering tropical moisture in the wake of Hanna could still bring 
heavy rain mainly along the central and eastern Gulf Coast next Monday and Tuesday.

Meanwhile, cooler and drier air behind a cold front will bring some relief from the heat and 
humidity first across the northern U.S., and then progressively eastward into the Northeast and the 
Mid-Atlantic by next Thursday.  Before the arrival of the cold front however, much above normal 
temperatures are expected for parts of the northern Mid-Atlantic into southern New England on 
Monday.  Meanwhile, high humidity farther south across a good portion of the Mid-Atlantic will make 
the heat feel very oppressive on Monday and Tuesday.  By the middle of next week, the trailing 
portion of the front is forecast to stall across the Mid-Atlantic and the Tennessee Valley.  This 
will increase the threat of heavy rain from Arkansas eastward across the interior Southeast into 
the Carolinas and southern Virginia from next Wednesday to Friday.  Farther west, additional 
monsoonal moisture over the central/southern Rockies will spread eastward into the Plains ahead of 
the stalled front, which could lead to heavy rainfall Monday and Tuesday for these areas.  Some 
quick-hitting heavy rain could also impact parts of the Ohio Valley and lower Great Lakes on Monday 
as thunderstorms are expected to form ahead of the cold front.

As the cool air mass settles into the northern and northeastern U.S. next week, the warm 
upper-level high will retreat westward into the western U.S.  This pattern will promote above 
normal temperatures in the interior western U.S., especially for the Pacific Northwest where high 
temperatures are forecast to top the century mark for the interior valleys next Monday through 
Wednesday.  The rest of the interior West should see above normal temperatures next week but at a 
tolerable level.  Cooler air should spread into the Pacific Northwest toward the end of next week 
as the next Pacific cold front arrives.

Over Alaska, heavy rainfall associated with a weakening low pressure system across the southeastern 
mainland into the Panhandle should be tapering off on Monday.  Farther north, models have trended 
toward a better defined low pressure system brushing across northwestern Alaska next week, with a 
well-defined front dipping into the area.  A heavy rain area has been introduced for the Brooks 
Range for Monday and Tuesday along a stalled front ahead of a quick-moving low pressure system from 
northeastern Siberia.  In contrast, the rain across interior southeastern Alaska appears more 
scattered and terrain-enhanced than earlier forecasts as models trend toward more ridging.

Finally, Hurricane Douglas continues to show a real threat to Hawaii with possible hurricane-force 
winds together with heavy rain and high seas on Sunday.  The storm should most likely be weakening 
further as it tracks generally west to west-northwest across the outer islands of Hawaii toward the 
middle of next week.

Kong