USA summer forecast 2016 by #Weather.com #summer #USA.
Warm Temperatures For Much of the U.S.
“Summer 2016 may be a warm one over much of the U.S. as a transition into La Niña conditions are expected, according to a June-August outlook released by The Weather Company’s Professional Division Friday.
Well-above average temperatures are expected this summer for the northern tier of states, from the Pacific Northwest into the northern Plains, Great Lakes and Northeast. Warmer than average temperatures will also extend from southern California into the central and southern Plains and Southeast. The only area where cooler than average temperatures are currently expected this summer is for portions of central and south Texas.
One of the factors to consider regarding temperatures this summer are sea surface temperatures in the Atlantic, which are forecast to be warmer than over the past five years. This would help to lead to a hot summer, especially in the East.
As mentioned above many computer forecast models are suggesting that the strong El Niño will transition to La Niña this summer. Typically, La Niña summers feature hotter temperatures from the central U.S. into the Northeast, with the hottest month being July.
Dr. Crawford points out that during other years where rapid changes from El Niño to La Niña occurred, “the summer heat is centered in the northern Plains into the Great Lakes states.”
Overall, computer forecast models are highlighting widespread warmth, with little hint of cooler than average temperatures in the U.S. There is the chance of cooler than average temperatures in the Southeast and West. However, above-average temperatures are expected to prevail across the West due to the influence of the strong El Niño we saw this past winter.
April Temperature Update
The focus of the warmer than average temperatures is expected to be across the West, especially the Pacific Northwest. Temperatures are also expected to be above average from the northern and central Plains into the Midwest and toward the East coast. Much of the southern Plains, Lower Mississippi Valley and parts of the Deep South will likely experience cooler than average temperatures during April.
The stratospheric vortex is undergoing a split, as of mid-March. Even though this split is unusually late, it seems that the corresponding wind reversal and increasing heights at the pole may impact conditions at the surface. Specifically, negative Arctic Oscillation conditions, or high-latitude blocking, are expected in April, which typically translates to below-average temperatures in the East and above-average temperatures in the West.
This high-latitude blocking is expected to be a primary driver of temperatures in April, with less influence coming from the tropics.
Climate model forecasts also agree on the very warm temperatures in the West, with the best chance of cooler than average conditions across the south-central U.S. There are some differences in the models regarding how far south colder temperatures will reach in the East, with some keeping the coldest conditions in eastern Canada.
Credit: Weather.com : https://weather.com/forecast/national/news/june-august-summer-2016-temperature-outlook