US Day 3-7 Hazards Outlook
NWS Weather Prediction Center College Park MD
332 PM EDT Fri Oct 09 2020
 
Valid Monday October 12 2020 - Friday October 16 2020
 
Hazards:
- Heavy rain across portions of the Pacific Northwest and the Northern Great Basin, Tue, Oct 13.
- Heavy rain across portions of the Mid-Atlantic and the Northeast, Mon-Tue, Oct 12-Oct 13.
- Flooding possible across portions of the Southeast, the Middle Mississippi Valley, the Lower 
Mississippi Valley, the Southern Plains, and the Tennessee Valley.
- Flooding likely across portions of the Lower Mississippi Valley.
 
Detailed Summary:

A low pressure over the Middle Mississippi Valley an associated warm front will move to the 
Mid-Atlantic Coast by Tuesday.  The warm front will aid in producing heavy rain over parts of the 
Mid-Atlantic and the Northeast on Monday.  Meanwhile, an area of low pressure will move into the 
Pacific Northwest, on Tuesday, moving inland to the Northern Plains on Wednesday and into the Great 
Lakes on Thursday.  Moisture associated with the storm will briefly stream moisture into the 
Pacific Northwest on Tuesday producing heavy rain over the area.  As the storm moves eastward high 
pressure will begin to move into the Northwest. The pressure gradient between the low and high will 
be strong on Wednesday but not strong enough to issue an area of high wind over the Northern High 
Plains and Central Rockies on Wednesday.  As high pressure builds over the Northwest and Great 
Basin the wind over Southern California will pickup on Friday.  

Over Alaska, low pressure over the Eastern Aleutian Islands, on Monday will slowly move eastward 
and weaken by Thursday while another area of low pressure over the North Pacific will move 
northward towards the Aleutians on Friday.  The first low will lack a strong moisture connection by 
this time so heavy precipitation is not expected from Monday into Friday.  Nevertheless, the timing 
of the heavy precipitation is subject to change as global models are indicating a great deal of 
uncertainty forecasting this active synoptic pattern. 

Ziegenfelder