1.   A heavy overcast like a poison gas cloud was stationary over the battered city.

2.   Another type of flash flood pattern occurs when very weak high-level winds cause individual thunderstorms to remain nearly stationary over the same area.

3.   But for the last several days, an enormous zone of high pressure has been stationary over the Southwest suppressing clouds and promoting the record heat.

4.   Cool, unstable air will cover the Northeast as an unseasonably strong low-pressure area becomes nearly stationary over southeastern Canada.

5.   Farther to the west, there will be showers and thunderstorms along the Gulf coast as a front becomes nearly stationary over the region.

6.   High pressure will remain nearly stationary over the South.

7.   Showers and thunderstorms are also likely across the central Plains as a weak area of low pressure becomes nearly stationary over the region.

8.   West of the Rockies, sunshine will be plentiful as very strong high pressure remains nearly stationary over the region.

9.   A frontal trough remains stationary over Hispaniola.

10.   After Friday, it remains to be seen whether this cold front will become stationary over Puerto Rico or continue to move east as a very weak cold front.