A warm fall may be ahead for those east of the Mississippi river and in the Northwest, according to the temperature forecast released by The Weather Channel Professional Division on Friday.
One of the biggest factors in the temperature forecast over the next three months is likely to be the strong El Niño event, which is expected to last into the winter. However, the strong blocking we have seen this summer is also expected to be an important contributor.
“The expected stronger El Niño state for 2015 will likely continue to limit tropical activity in the Atlantic basin this summer/fall, and increase the chances of a mild winter across much of the northern U.S.,” said Dr. Todd Crawford, WSI chief meteorologist. “The strong summer blocking implies that big winter blocking is possible this year, which may override the El Niño signal.”
The period from September to November is expected to see temperatures well above average in portions of the Southeast, including Florida, as well as the Northwest, including most of Washington and western and northern Oregon. Overall, the East can expect temperatures to be warmer than average, while much of the Plains and parts of the Southwest will see a greater chance of cooler-than-average temperatures.
In September, the core of the below-average temperatures will be found in the West, with the exceptions of Washington, Oregon, northern and central California as well as parts of western Nevada, northern Idaho and far northwest Montana. Meanwhile, those in the East will see mainly above-average temperatures with the Southeast and portions of the Mid-Atlantic seeing temperatures well above average.
In October, there is good agreement in the climate forecast models for below-average temperatures to be confined mainly to portions of the Plains, while both the East and West Coast can generally expect the warmth to continue, says Crawford. However, this is contradictory to what is expected during a strong El Niño event.
The current forecast for October leans toward the climate forecast models with cooler conditions in the Southern Plains and parts of the Southwest, with warmer than average temperatures in the northern tier, as well as towards both the East and West coast.
Crawford explains that the climate models are in agreement with establishing the classic El Niño winter signature in November. This indicates warmer-than-average temperatures in the northern tier and colder-than-average conditions in the southern tier.
The November forecast highlights the above-average temperatures to remain in the Northwest, as well as in much of the East, while below-average temperatures will stretch from Southern California to Louisiana and northward into the northern Plains and Upper Midwest.
Although many will enjoy the above-average conditions this fall, warm temperatures may not be good news for the drought and fire risk in the West.
Heading into late fall El Niño may become a more important factor in weather patterns, but it is important to remember that there are numerous factors that play a role in determining the outcome.