Summer of Simmer, Mid Week Update: July Going For Bronze Silver

July 23, 1 AM Update: The midnight (standard time) temperature of 82° is in, so the low of 79° holds, just 2° below the record high minimum for the date. A couple of high minimum records are vulnerable over the weekend with 78° on Saturday and 79° on Sunday and Monday.

Summer-to-date average: 81.5°.

NOAA's Climate Prediction Center data shows that the 31-day running mean of temperature departures has not been negative since the end of February.

July 22 Update: The preliminary high/low of 96° and 79° today push the month to date (2010 TD) to 82.8°, firmly in position as the 3rd hottest July. The projection (2010 Proj) moves to 83.0°, tied for 2nd and within striking distance of the record for hottest July.

PM Update: Today's preliminary high comes in at 93° with a low of 75°.

Original post:
High temperatures generally in the low 90s (including a high as of 2 pm today of 91°) and lows in the mid 70s so far this week have continued to inch the Washington cumulative summer average higher, to 81.4° through yesterday. Forecast temperatures in the upper 90s to near 100° over the weekend will likely push it even further, to 81.8° by Sunday. Even with normal temperatures from the remainder of July through August, the final summer average would be 80.2°, a new record high.

Meanwhile, the July monthly average continues to increase as well, standing now at 82.6° (2010TD on the chart), tied with 1987 for third hottest July. Projections based on the next 7 days of forecasts and climatology would keep the final monthly average at the same value (within rounding error).