Prohibitive cooler changes are indicated by the 12Z GFS in the Upper Midwest to Quebec in the 6-10-day period followed by much stronger cooler changes from the Midwest to the Northeast Corridor in the 11-15-day period.

A tropical upper tropospheric trough (TUTT) pattern has developed in the Caribbean Sea. The upper trough slowly drifts westward this week and is replaced by a second trough next week a little further to the north. The TUTT formed by release of shortwave energy from an energetic mid-latitude flow across the central North Atlantic basin southwestward into the tropics.

The Nino SSTA regions are all within neutral range entering July. Recent warming in the Nino12 region off the northwest coast of South America has eased back into the neutral range.

The NOAA 2-day forecast track indicates Chantal turns northward across central North Carolina later today and weakens completely drifting across Chesapeake Bay late tomorrow. The heavy rain/flood risk shifts to north-central South Carolina and central North Carolina today and across Eastern Virginia to near Philadelphia tomorrow.