CHILL IN THE AIR
Fans of the 'fall-like feel' were treated to chilly air early friday morning. For some outlying areas this was the coolest morning of the season. Notable low temperatures included 38° at Marion (Grant Co), Zionsville (Boone Co), Lafayette (Tippecanoe Co) and 37° in Kokomo (Howard Co). The coolest local temperature is Crawfordsville dipping to 36°. In Indianapolis the low of 46° beat the coolest so far this autumn of 47° set twice last weekend.
Dry air heats up and throw in sunshine and a south breeze our temperatures are once again on the rise. By late Friday afternoon there was as much as a 25 to 30 degree rise from the early Friday morning temperatures. Friday's temperature average will enter the books as a 'normal' day. Fall 2015 nears its half-way point ranked 9th warmest all-time. At it is going to get warmer.
WINDY - WEEKEND
When unseasonably warm air arrives it usually comes on the heels of strong winds. Southwest winds will gust to 25 mph Saturday and over 30 mph Sunday through Tuesday.
RECORDS MAY FALL
Warm low temperatures along with afternoon high temperatures are in jeopardy in the coming days. Temperatures will climb through the 70s over the weekend and reach low 80s Monday and Tuesday threatening decades old records. Monday the record of 86° set in 1950 looks to stand but Tuesday's record 84° set in 1953 and 1938 could be broken.
WHY SO WARM?
Temperatures are likely to warm 15 to 20 degrees above normal for much of the eastern U.S. the produce of a strong west to east jet stream roaring off the pacific. A powerful storm blasts the pacific northwest and the air flows up and over the Rockies. That air then sinks in the central plains, and compresses. Air, like any gas when compressed heats up. The warm spreads east and the central and eastern U.S. is bathed in unseasonably warm air.
Regardless of records, it is rare to have multiple days of 80° warmth beyond the 15th of October. The last time came in 1989 with 2 days. The most 80° days after October 15th came in 1963 with 9 days. The latest last 80 degree day came on November 1st, 1950.