Ensemble models (at least the North American ensemble) have returned to a primarily warm regime for the lower 48 for the period of the 16-23. Above average temperature are forecast over all of the US mainland except over northern New England and the SE where temperatures will be near normal and S Florida where temperatures are forecast to be below average for the period. Models have been having having great difficulty lately with consistency, not only in the week 2 outlooks but in the week 1 details. So this forecast is low to very low confidence.

This week will see a flow of quite mild pacific air flood across the Rockies into the Plains, midwest early and into the Great Lakes states by Tuesday. Early this week will see very mild conditions over the Plains and midwest. In the meantime a strong low pressure area will develop over Manitoba and track thru northern Ontario Wednesday. Behind this low a very strong cold front will plunge thru the northern Plans Wednesday morning, extending from Detroit to Southern OK by Thursday morning. Cold air will move very quickly E but not much further South after this. This week NYC, for example, will go from near average to very mild mid week to well below normal by Saturday morning.

At the same time a trough of low pressure crossing thru Southern AZ this morning (powered by a southern branch of the jet stream) will provide the energy to develop a low pressure area over extreme SW TX tomorrow morning that will lift NE and bring some rain to E TX, the gulf coast states and the SE this week. It will deepen rapidly over the DC area Thursday morning and bring heavy rain and a mild though strong wind to NJ, NY and New England Thursday, followed by the previously mentioned sharp cold front Thursday eve/Friday morning.