Cooler Weekend Ahead

August & September Heat Ends
The hot weather pattern that has gripped the state for nearly a month straight has finally ended its run. From August 19-September 11th, the high has managed to reach 84+ except one day, which was September 3rd (High 76°). In between this time period, 22 days finished with at or above normal temps and we racked up 9 days with highs 90+. The last 6 days of August saw a streak of 90+ degree heat and this was the longest streak so late in the season since August 28–September 1, 2010. On August 31st the high temperature reached 96° this is also shared with September 11th as the hottest days of the year. From Monday, September 9th-Wednesday, September 11th we saw 3 consecutive days with temps 93+. During these 3 days, the average temperature (combo of high and low temp) was above 80+. The last time this occurred so late in the year was 74 years ago in 1939. Also, as I've posted in my previous blogs, we've tied the warmest low record for September 10th & 11th, we broke the record high for September 10th & tied the record high on the 11th.

DAY OF THE WEEK	RECORD HIGH TEMP	PREVIOUS RECORD TEMP	HIGHEST MINIMUM TEMP	PREVIOUS RECORD TEMP
TUES SEPT. 10th	96° (NEW RECORD)	95° (1964/1983)	74° (TIED)	74° (1919)
WEDS SEPT. 11th	95° (TIED)	95° (1897)	72° (TIED)	72° (1900/1931)

Normally, you don't think of 90s when you hear the month September but we average 2 of them (this month) and we got 3. 4 out of the past 6 Septembers saw 90s and even triple digits (2011). The season's have been arriving rather late this year but as the days continue to grow shorter the temperatures will only continue to trend cooler from here on out as the fall and winter months approaches. We lose a total of 74 minutes (1 hr 14 mins) of daylight this month and the average high decreases to the low 70s and the average low decreases to the low 50s by month's end. History shows that we're bound for a 60° high and a 40° low.



ABNORMALLY DRY PATTERN CONTINUES
The latest drought analysis map was just issued Thursday morning but it didn't take into account the rain most received Thursday morning. The cutoff time for the data collected was back on Tuesday at 7am. The map shows now 8% of the state is in a moderate drought which up from last weeks 2%. 44% of the state is abnormally dry also up from last weeks 36%. Basically Central, Northwestern, and Northeastern parts of the state is abnormally dry, some worse than others. I've updated my rainfall deficit chart (rainfall values are valid thru 4pm Thursday) Most areas south are actually doing well. Evansville is still over 4" above normal for the year. Those in Ft Wayne are also 4" above normal for the year. Here in Indianapolis, Thursday marked the 2nd time out of the past 33 days since August 10th to see measurable precipitation. We are almost 5" below normal since June 1st and nearly an inch below normal for this month. The worst spot is Shelbyville. They've had a tough time getting saturated. They've been below normal for quite some time now and they're in a deficit for the year by over 9".

LOCATION	YEAR TO DATE PRECIP (thru Sept 12)	DEPARTURE FROM NORMAL	PRECIP SINCE JUNE 1	DEPARTURE FROM NORMAL	MONTH TO DATE PRECIP	DEPARTURE FROM NORMAL
BLOOMINGTON	30.75	-3.76	11.74	-2.88	0.43	-0.89
EVANSVILLE	36.53	+4.41	13.95	+2.07	1.20	+0.00
FT. WAYNE	32.58	+4.60	14.91	+1.73	0.24	-0.90
INDIANAPOLIS	30.19	-0.37	8.36	-4.80	0.26	-0.97
INDIANAPOLIS EAGLE CREEK	27.63	-1.90	8.79	-3.93	0.14	-0.74
LAFAYETTE	28.43	+1.79	9.81	-2.81	0.80	-0.29
MUNCIE	25.83	-3.34	10.02	-3.58	0.95	-0.31
SHELBYVILLE	22.07	-9.50	9.76	-4.03	0.66	-0.63
SOUTH BEND	27.18	+0.49	9.88	-3.09	0.26	-1.16
TERRE HAUTE	33.08	+0.28	12.05	-2.31	0.05	-1.47

Rainfall numbers over the next 2 weeks shows things may get interesting. 18z GFS Run hints at nearly 2" of rain by September 28th but we all know this is subject to change. I will note though, wild temperature swings are known to spin up storms as we go through the change of seasons.

Thursday' high was 83°. Avg is 79°. 4° above normal.
Thursday's low was 63°. Avg is 58°. 5° above normal.
Thursday's Precipitation Amount was 0.26. This is also the months total precipitation amount which is 0.97" below normal.

Under a north wind and the passage of a few cold fronts, the dew points drop, the humidity clears, and the temperatures fall to its lowest in months. We could be looking at highs struggling to top 70s on Friday and Saturday. Low Temperatures may fall back into the 40s for Saturday morning. Temps will make its way back up towards the 80s Sunday and Monday and nearing mid 80s on Tuesday. Weekend rain chances are slim under a Canadian high. There is a small chance for a few sprinkles on Sunday but not promising. Our biggest chance for rain or thunderstorms will be next Thursday behind another short heat surge that will lead temps to fall back for next weekend.

NEXT WEEK
Again, there are some indications on some of the latest model runs that we may not exactly be down just yet with this summer heat and we'll need to watch Wednesday, September 18th for another potential 90° day. For those wondering the latest 90° day on record is held October 8, 2007. This is actually an interesting weather stat because October 7th marks the average date for our 1st frost. More details to come soon. Here's 2 meter (°F) temps for September 18th from the Thursday mornings 12z European Model run.


***8 DAY OUTLOOK***
 SUNRISE: 7:24AM | SUNSET: 7:56PM | DAYS UNTIL AUTUMNAL (FALL) EQUINOX: 9
 AS THE DAYS GET SHORTER & NIGHTS GET LONGER, SUMMER WILL FADE & FALL WILL INVADE
 2 OUT OF PAST 33 DAYS SAW MEASURABLE RAIN (AUG 10-SEP 12) | AUG 31st SNAPS 21 DAY DRY STREAK

SEPT. 13	SEPT. 14	SEPT. 15	SEPT. 16	SEPT. 17	SEPT. 18	SEPT. 19	SEPT. 20
FRIDAY	SATURDAY	SUNDAY	MONDAY	TUESDAY	WEDNESDAY	THURSDAY	FRIDAY
SUNNY & NICE	SUNNY & NICE	PARTLY SUNNY	SUNNY SKIES	MOSTLY SUNNY	SUNNY & HOT!	T'STORM CHANCE	PARTLY SUNNY
COOLER	OCTOBER LIKE	CHANCE OF RAIN?	NICE DAY!	WARMER	REC HIGH 95°	NOT AS WARM	MUCH COOLER WX LOOMS
70	70	76	78	82	90	85	80
48	52	55	58	63	70	67	57