Temperatures for the week averaged warmer than normal over the southern Plains to Lower Mississippi Valley and across parts of the Southwest and Northwest. The rain missed large parts of the West, which received little to no precipitation, and much of the Plains, Mississippi to Ohio Valleys, and Southeast to Mid-Atlantic states were drier than normal as well. The end result was a weekly precipitation pattern that was wetter than normal over parts of the West, southern Plains, Great Lakes, Northeast, and southern Florida. Monsoon showers joined in over the Southwest in these waning days of summer. The trough generated a storm track across the northern states, then sent a large cold front into the Southeast as the period ended. The high pressure ridge brought hot temperatures to the southern states at first, then to the West later in the period. Other players danced at the periphery – Hurricane Fiona moved across the Canadian Maritime Provinces, spreading rain over New England at the beginning of the week, while Hurricane Ian brought rain and wind to southern Florida as it bore down on the state just as the week ended. As they did a kind of do-si-do, the ridge swung from the southern Plains to the western CONUS. The other partner was a high pressure ridge.

One partner of the pair was an upper-level low pressure trough which twirled from the West Coast to the northern Plains then migrated to the Northeast. Drought Monitor (USDM) week (September 21-27).

Two upper-level weather systems danced across the contiguous U.S.

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