Warm September, Wet October, Cold November

Lots of twists and turns in the weather department for the Fall season. Here's my recap of the season. Lots of good info here. Enjoy!

SEPTEMBER 2013
We did open the month warm. We were caught up in the passage of 2 frontal systems. The high temp of 85 on the 1st was knocked back to 76 on the 3rd. Though we only recorded a trace of precipitation, the cool down was very brief and warmer temperatures quickly returned. Its interesting to note that the 1st 11 days (except September 3rd) saw a high 84+. This was actually nearly a continuous streak that started back on August 19th (23 of 24 days). We reached the 90s from September 9th-11th. On September 10th we reached a record 96° & tied the warmest low temp of 74. This was the hottest day since August 8, 2012. Then On September 11th, we tied the record high of 95 and tied the warmest low of 72. The daily average temp during the period of Sept 9th-11th was 80+, the last time this occurred so late in the year was 74 years ago in 1939.

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)

A series of four cold fronts quickly moved in behind the record heat. The high temperature was 95 on the 11th, 83 on the 12th, & then 69 on the 13th. This was a 26° drop in the highs in 48 hours. The low temperature was 72 on the 11th, 63 on the 12th, and 53 on the 13th. This was a 19° drop in the lows in 48 hours. Overall, temps drops 20-25° in 48 hours but the drop doesn't stop there. The AM low temperature on the 14th was 48°. This was the coolest low since June 3rd. The 69° high on the 13th was also the coolest high since June 3rd. Even after several of these frontal systems, we only recorded a quarter of an inch of precipitation during the 1st 19 days of the month. There was a slight warm up back to the low 80s as a warm front pushed through but this was associated with a storm system that brought severe weather or rather thundery downpours to the state on the 19th. Indianapolis recorded 1.53" of rain on the 19th w/ an additional 0.49" on the 20th ending with 0.02" early on the 21st (see breakdown in image below). 2.04" of rain for September 19-21 is the wettest at one time since 2.29" fell on April 18th.
Since the average temperature was decreasing during the month, we were able to finish the month warm enough to be 1-7ˌ above normal from the 24th-30th. This put the months average temperature at 69.5° which was 2.6° above normal (66.9°)
On the 29th, another cold front moved through that also generated a half inch of precipitation. This brought's the months final rainfall tally to 2.86". The month finished 0.26" below normal (3.12").
Overall, September 2013 finished as the 36th warmest and 69th wettest on record.

There was sightings of fireballs late September. The AMS received nearly 700 reports of a large fireball the morning of September 26th around 7:05 am local time. Witnesses from Ohio, Illinois, Indiana, Kentucky, Missouri and Wisconsin reported a bright light moving across the morning sky. Check out the heat map to the right. The AMS is always receiving reports of fireballs, some of which have yet to be reviewed or confirmed. You can check the reports at the following url address:

http://www.amsmeteors.org/fireballs/fireball-report/




OCTOBER 2012

We opened up the month of October as the 12th warmest on record for the 1st five days w/ an average temperature of 71°. Also, the 1st five days was the warmest since 72.3° in 2007. A few fronts allowed high temperatures to drop into the mid to low 60s for October 6th & 7th. These cool temps were a response to a passage of a powerhouse frontal system that 1st dropped 2+ feet of snow in the Plains and spawned tornadoes in the upper midwest, and later generated nearly 3" of rain in Indianapolis. We set a daily record rainfall on October 6th. The 1.45" of rain we received bested a 15 yr old record of 1.41" set in 1998. We then went into a dry streak that lasted a week as high pressure parked itself in the Midwest region. This prolonged period of dry warmer resulted in above normal temps bringing pleasant fall weather to the state. A weak frontal system that passed the state overnight on the 12th into the 13th little to no precipitation was generated across the state.

Some what of an unsettled pattern brought more rain to the state from the 15th-19th bringing a little less than half an inch of precipitation over this 5 day period. The wet weather was also associated with the switch to a cooler weather regime that brought below normal temperatures for the remainder of the month. A cold front moved through on the 21st which allowed temperatures to drop below freezing the morning of the 22nd (low was 30°). It was the 1st fall freeze for Indianapolis since April 20th, a span of 185 days. With a low pressure system in the area, temperatures continued to remain anywhere from 3 to as much 22 degrees below normal from the 21st-27th. We recorded trace amounts of wintry precipitation (such as graupel, sleet, & snow flurries) on the 23rd and 24th. We also recorded our 1st Hard Freeze (28° or below) on October 25th when the low reached 26°. This was 17° below normal (43°) and was the coldest since 25° on April 3rd, a span of 205 days.
On the 27th, there was a slight pullback in the chill and temperatures began to respond reach 60s on the 28th, 30th, and 31st. This snapped a 14 consecutive day streak of below normal temperatures. Its was the longest stretch of below normal temperatures since the 19 day streak that ran from March 12th-30th earlier this year. This warm-up came w/ a price. A price that put a damper on Halloween plans. A large supply of Gulf moisture feeding into a monster low pressure system ahead of a cold front allowed for widespread precipitation across the Midwest region spawning up tornadoes & record rainfalls. All but 1 of these tornadoes were rated EF1 or weaker doing some damage in Texas, Louisiana, Missouri, Arkansas, Kentucky, Illinois, and Ohio. There was one EF2 tornado that impacted Stoddard, Missouri which is located about 150 miles south of St. Louis. Overall, 26 of 46 tornadoes reported have been confirmed.
We didn't have severe weather of that magnitude closer to home. We recorded wind gust in excess of 40 mph across the state. Muncie, Indiana recorded a 75 mph peak wind gust. This was of hurricane strength. In Indianapolis, we recorded a peak wind gust of 58 mph which was the highest wind gust since 59 mph was recorded back on February 19th. As for rainfall, many locations around the state broke their Halloween record rainfall amounts. In Indianapolis, 2.01" of rainfall fell which bested a 72 year old rainfall record of 1.30" set in 1941. Only 39% of the Halloweens over the past 140 years have recorded measurable rainfall. A few other record rainfall amounts were set in; Terre Haute (2.42"), Ft. Wayne (1.73"), Lafayette (1.51"), and Muncie (1.18"). The record of 1.16" was tied in Shelbyville. For other info on the Halloween storm you read the NWS Indianapolis, IN write up on it (click the link) Review of Halloween 2013 Severe Weather
We received 82% (2.57") of our average month's rainfall (3.12") within the 1st 10 days of the month. The average precipitation amount for the 1st 10 days of the month is 1.05" The total precipitation amount for October 2013 was 5.46". This was 2.34" ABOVE NORMAL. As for the month's average temperature of 54.6ˌ, the month finished finished 0.6° BELOW NORMAL.
Overall, October 2013 finished as the 57th Coolest and 12th Wettest October on record.

NOVEMBER 2013

Though nearly seasonable air lingered from late October to the 1st 11 days of November, 11 out of the 17 days from the period of October 26th-November 11th saw below normal temperatures but high temperatures were primarily in the 50s and 60s. Lows for these days were primarily above freezing.
A dry cold front passed early on the 10th. Highs on Sunday the 10th was 10° cooler with temperatures struggling to top the 50s in many locations. Temperatures were nearly identical for the 11th but arctic air was on the move and came in Monday evening. Widespread rainfall made a transition as the lake effect snow machine was turned on and nearly everyone around Indiana saw their 1st measurable snowfall of the season on the 12th. Anywhere from a dusting to 1.5" fell around the state. 0.1" fell in Indianapolis which was the 1st measurable snowfall here in 231 days when 0.1" fell on March 26th. This was also 7 days before the average date of 1st measurable snow which is November 19th. Some counties up North near the lake where snow persisted saw more than 6" of snow. Saint Joseph, Michigan recorded 17". Nearly 55% of the Great Lakes Region was covered in snow. The location of where the heaviest band setup was very selective. Chicago only recorded 0.4" at their NWS office at O'Hare International Airport.

As the warm air quickly dissipated and the snow fell, temperatures tumbled into the low 20s for Tuesday morning lows. As the chill settled in, Tuesday afternoon high temperatures only made it a few degrees above freezing. The high of 36° on the 12th was the coldest high temperature since 34° was recorded on March 25th. These temperatures were 15°-18° below normal and the high was 1° below the average low temperature. On the 13th, arctic air continued to work in and the morning low temperature dropped into the teens (18°). It was the coldest in 237 days when the thermometer dropped to 16° back on March 21st. It was also the coldest start to a November day in 5 years when the thermometer dropped to 17° on November 22, 2008. Since weather records began in 1871, only 73 out of 143 Novembers have produced a low of 18° or colder, the coldest was -5° in 1880. This cold air so early in the month is rather rare & quite impressive. It was only the 27th time on record the low of 18° or colder occurred before November 13th and the first time in 18 years!
On the 14th, the cold air was beginning to retreat. The morning low dropped to 26° and afternoon temperature warmed up 27° to a high of 53° and on the 15th the AM low was 40° and the afternoon high was 54°. The warm temperatures continued for the 16th and 17th as highs surged into the low to mid 60s. A cold front along with an intense low pressure system stirred up a severe weather event on November 17th that brought a tornado outbreak to the Midwest, Great Lakes, and Ohio Valley Region.
There was about 72 confirmed tornadoes across; Indiana (28), Ilinois (25), Kentucky (6), Michigan (5), Ohio (5), Tennessee (3), and Missouri (1). One of these tornadoes struck 2 states (that is why math comes to 73). The 28 tornadoes that struck Indiana is the 3rd highest tornado outbreak for the state behind June 2, 1990 (37) and April 19, 2011 (29). It was the most active tornado day in Indiana for November, nearly doubling the previous daily record of 15 tornadoes from November 22, 1992.
As for fatalities it appears there were 7 in Illinois and 3 (non tornadic) in Michigan. As you know, a rare "high risk" for severe weather was issued by SPC for a large part of the Midwest & Ohio Valley Region, for only the second time in 2013. The 1st time was back on June 12th when a Derecho passed through the Midwest, Great Lakes, and Ohio Valley Region. It was also the first time in November since November 15, 2005 and 4th time for a November since November 15, 1989. I've provided a photo below shared on Twitter by Eric Fisher (Chief Meteorologist for WBZ-TV in Boston, MA). Its the Day 1 Convective Outlook overlayed with the storm reports. The heaviest concentration of reports were within the "High Risk" and "Moderate Risk" area which proves the accuracy of the forecast for this severe weather event. Weather watches and warnings are issued for a reason and should be heeded and not taken lightly. THIS WAS NO JOKE AT ALL!
Indianapolis recorded a peak wind gust of 67 mph, which is the highest for the year. Additionally, a record (daily) rainfall amount of 2.48" was recorded (for November 17th). This broke a 127 year old record of 1.97" set in 1886. This is the wettest day of the year and wettest since 2.71" fell on September 7th, 2012. For more info on the outbreak, you can read NWS Indianapolis, IN write up on it. (Click the link) Review of the November 17 Central Indiana Severe Weather and Tornado Outbreak

Temps were nearly normal from the 18th through 22nd, but a stronger cold front passed late November 22nd ushering in the coldest temps since Feb 20th. On November 24th, the high was 26 and the low was 13. Combined, the average temp was 21. This was not only the coldest day of November 2013 and the coldest in 277 days (FEB 20th) but also the coldest November day in 8 yrs when the high was also 28° back on November 25, 2005. This was also the last time the average daily temp was that low for a November day. This day finished nearly 20° below normal.
The high temperature on the 28th was 36° and the low was 16°. This was 11th coolest Thanksgiving morning since 1871 and coldest Thanksgiving morning since November 24, 2005. We saw the coldest Thanksgiving afternoon in 9 years when 36° was also recorded for the high in 2002. Thanksgiving 2013 was 27° colder than last year and finished 12° below normal.
Impressive chill huh? The average temp from November 23rd to 28th was 25.6°, this was ranked as 6th coldest for the period. 6 out of the 7 days from November 23rd-29th saw highs near or below freezing and low temps in the teens. There was a total of 7 days w/ lows in the teens for the entire month. Most for this occurrence for a month of November in 37 years when we saw 10 days with lows 19° or below in November 1976.
The average month's high temperature was 47.4°. This was 4.8° below normal (52.2°).
The average month's low temperature was 31°. This was 4.1° below normal (35.1°).
The average month's temperature was 39.2°. This was 4.4° below normal (43.6°).

As for precipitation for the month, a trace or more of rainfall was recorded on the following days:
November 1:  Trace
November 2:  Trace
November 4:  0.01"
November 5:  0.34"
November 11: 0.05"
November 12: Trace
November 16: 0.04"
November 17: 2.48"
November 21: 0.23"
November 22: 0.08:
November 23: Trace
November 26: Trace
November 27: Trace
Total precipitation was 3.23". This was 0.37" below the normal amount of 3.70". Additionally, traces of wintry precipitation was recorded on 12th, 23rd, 26th, and 27th. 0.1", recorded on the 11th, was the months total snowfall amount which finished 0.6" below the normal amount of 0.7".
Overall, November 2013 finished as the 23rd Coolest and 79th Driest November on record.

METEOROLOGICAL FALL (SEPT 1-NOV 30)

As a season, fall started off warm. 33 (or 73%) out the 1st 45 days saw above normal temperatures. Temperatures were running 5° above normal for the period of September 1-October 15. September was dry but October was wet. We saw 10 days w/ a trace or more of precipitation in September totaling 2.86". In October we saw 15 days w/ a trace or more of precipitation totaling 5.46". The 1st half of October saw above normal temperatures but that switched to slightly below normal temps for the the 2nd half of October. Below Normal temperatures prevailed in November. Only 10 out of 30 days saw normal or above normal temps. Precipitation in November was slightly below normal.
50.5% of the days saw below normal temps, 47.3% of the days saw above normal temps, and 2.2% of the days saw normal temps.
The average high for the Fall season was 63.9°. This was 1.1° below normal (65°).
The average low for the Fall season was 44.9°. This was 0.3° below normal (45.3°).
The average temp for the Fall season was 54.4°. This was 0.8° below normal (55.2°).
The total precipitation amount was 11.55°. This was 1.61" above normal (9.94").
The total snowfall amount was 0.1". This was 1" below normal (1.1").
Overall, Fall 2013 finished as the 54th Coolest and 30th Wettest Fall season on record


Here's how the year's weather measures up so far in terms of averages and rankings.

MONTH	AVG TEMP	TEMP DEPARTURE FROM NORMAL	TEMP RANKING	TOTAL PRECIP	PRECIP DEPARTURE FROM NORMAL	PRECIP RANKING	TOTAL SNOWFALL	SNOWFALL DEPARTURE FROM NORMAL	SNOWFALL RANKING
JANUARY	29.9°	+1.8°	58th Warmest	5.51"	+2.85"	16th Wettest	2.4"	-6.2"	35th least snowiest
FEBRUARY	30.9°	-1.2°	66th Coolest	2.27"	-0.05"	71st Driest	2.6"	-3.9"	46th least snowiest
WINTER '12-'13 (DEC-FEB)	33.1°	+2.6°	28th Warmest	10.36"	+2.21"	28th Wettest	19.8"	-2.2"	44th Snowiest
MARCH	35.5°	-6.7°	14th Coolest	1.96"	-1.60"	30th Driest	14.5"	+11.9"	4th Snowiest
APRIL	52.5°	-0.5°	74th Coolest	8.59"	+4.78"	2nd Wettest	TRACE	-0.2"	N/A
MAY	65.4°	+2.7°	34th Warmest	3.50"	-1.55"	60th Driest	NONE	0.00"	N/A
SPRING 2013 (MARCH-MAY)	51.1°	-1.5°	49th Coolest	14.05"	+1.63"	37th Wettest	14.5"	+11.7"	4th Snowiest
JUNE	72°	0.0°	71st Warmest	3.66"	-0.59"	69th Driest	NONE	0.00"	N/A
JULY	73.9°	-1.5°	30th Coolest	3.29"	-1.26"	71st Driest	NONE	0.00"	N/A
AUGUST	74.9°	+0.7°	43rd Warmest	1.15"	-1.98"	12th Driest	NONE	0.00"	N/A
SUMMER 2013 (JUNE-AUGUST)	73.6°	-0.3°	62nd Coolest	8.10"	-3.83"	33rd Driest	NONE	0.00"	N/A
SEPTEMBER	69.5°	+2.6°	36th Warmest	2.86"	-0.26"	69th Wettest	NONE	0.00"	N/A
OCTOBER	54.6°	-0.4°	57th Coolest	5.46"	+2.34"	12th Wettest	TRACE	-0.4"	N/A
NOVEMBER	39.2°	-4.4°	23rd Coolest	3.23"	-0.37"	79th Driest	0.1"	-0.6"	N/A
FALL 2013 (SEPT-NOV)	54.5°	-0.8°	54th Coolest	3.23"	-0.37"	30th Wettest	0.1"	-1"	N/A
JAN-NOV	52.4°	-0.2°	N/A	41.48	+2.21"	N/A	19.6"	-0.4"	N/A

WINTER 2013-2014 PREVIEW
Astronomically, fall doesn't officially end until the winter solstice on Saturday, December 21st at 12:11pm. The 3 coldest months of the year (DEC-FEB) is classified as meteorological winter. Here's some stats on the snow we typically see in Indianapolis during a normal year.

2013-2014 Winter Climate Outlook
NOAA released the outlook in November for 2013-2014 winter season. Since El Nino and La Nina isn't exactly present then there wasn't a clear weather pattern present to accurately forecast this winter's outlook. Therefore, they called for an equal chance of above, below, or near normal temperatures and precipitation/snowfall for the coming winter season. However, when an El Nino and La Nina isn't present, other weather patterns come into play. We look for a "Greenland Block" where high pressure is centered over Greenland. Low Pressure can be stuck for days clogging up patterns in the Eastern half of the U.S. This can result in below normal temperatures and above normal precipitation and snowfall. This particular pattern maybe the setup for the coming winter. Some things we'll need to watch is either for a weak El Nino and/or an active southern jet. So, here is where I think we'll stand in terms of snowfall potential and temperature trends this winter:

• NEAR NORMAL TO ABOVE NORMAL SNOWFALL: The setup for each storm system is impossible to predict. However, trends suggest we're likely to see seasonal snowfall totals that exceed 20". There will likely be gaps of dry weather so we may go time to time without any snowfall. These storms may come in waves that may bring over 2" of snow for each event. Also, we'll need to watch for Lake effect snow showers. These can bring some accumulations as well. A normal winter sees 25.9"
• BELOW NORMAL TEMPERATURES: We're likely to see blasts of Cold Air (frequent arctic intrusions) interrupting brief periods of mild temps resulting in below normal temperatures.
  -Average Temperature in December is 31.6°. I think we finish below normal.
  -Average Temperature in January is 28.1°. I think we finish below normal.
  -Average Temperature in February is 32.1°. I think we finish below normal.
  -Overall Average Winter Temp is 30.6°. I think we finish below normal.