Coastal North Carolina's Second 500-Year Rainfall in 11 Years

Oct. 5 Update: The flood waters have still not receded in many of the affected areas of North Carolina:
N.C. begins to survey damage from rain and floods

9 PM Update: The rain finally ended at Wilmington a little before 7 pm. The 6-hour total precipitation ending at 8 pm was 1.27".

6 PM Update: Wilmington has received 0.14" more in the last hour as the rainfall has diminished to moderate.

Elizabeth City's total so far today of 4.09" is still short of the record 4.52" for the date.

The 2.53" at Richmond VA is below the record of 2.85".

Today's 5.62" at Norfolk VA through 5 pm is a new record for the date. It's the third highest daily record for all of September. An additional 0.19" has fallen in the last hour.

5 PM Update: The 0.42" in the latest hour brings the 3-hour total to 1.11". As of 4 pm, today's total was 1.74" and September to date was 22.17".

Added Hurricane Floyd precipitation map (click to enlarge) from Climate Prediction Center/NOAA and links to Floyd reports.

4 PM Update: Heavy rain continues, 0.39" more in the last hour.

3 PM Update: An additional 0.30" has fallen in the last hour with visibility reduced to 1.5 miles in continuing heavy rain.

Original post:
Excessive rainfall in the Cape Fear region of North Carolina from a tropical conveyor belt including the remnants of Tropical Storm Nicole has broken the total rainfall record from Hurricane Floyd in 1999. The Floyd rainfall has been described by the National Weather Service as a once-in-500-year event.

The NWS reported this morning that the 19.66" at Wilmington in the 3 days ending yesterday is the highest 3-day total precipitation in records that began in 1871. The 10.33" on Monday is also the second highest all-time single day amount following Floyd's 13.38" on Sept. 15, 1999. The September total so far of 20.84" through this morning is the second highest for the month behind 1999. Heavy rain is continuing at Wilmington, and an additional 0.45" has fallen in the 6 hours ending at 2 pm EDT.

The map to the right (click to enlarge) from NWS shows North Carolina 7-day total precipitation ending at 8 am EDT this morning. The purple area extending from eastern South Carolina northward through the southeastern coast of North Carolina and to the Virginia border represents 10-15" of precipitation, with a smaller area near the coast of 15-20".

According to the NWS report, here is how the current event fits in with previous history:

OBSERVED TOTALS...  
SUNDAY    SEP 26   0.59 INCHES  
MONDAY    SEP 27  10.33 INCHES  
TUESDAY   SEP 28   1.96 INCHES  
WEDNESDAY SEP 29   7.37 INCHES  
THURSDAY  SEP 30   0.41 INCHES (1-3 INCHES MORE POSSIBLE)  
  
1-DAY ALL-TIME RECORDS...  
#1  13.38 INCHES   9/15/1999 (HURRICANE FLOYD)  
#2  10.33 INCHES   9/27/2010 (MONDAY'S EVENT)  
#3   9.56 INCHES   8/31/2006 (TROPICAL STORM ERNESTO)  
#4   9.52 INCHES   9/29/1938  
#5   8.04 INCHES   8/18/1879 ("GREAT BEAUFORT HURRICANE")  
  
2-DAY ALL-TIME RECORDS...  
#1  17.71 INCHES   9/15 & 9/16 1999 (HURRICANE FLOYD)  
#2  14.73 INCHES   9/14 & 9/15 1999 (HURRICANE FLOYD)  
#3  12.29 INCHES   9/27 & 9/28 2010 (MONDAY/TUESDAY'S EVENT)  
#4  11.87 INCHES   10/7 & 10/8 2005 (TROPICAL STORM TAMMY)  
#5  11.54 INCHES    7/7 & 7/8 1950  
  
3-DAY ALL-TIME RECORDS...  
#1  19.66 INCHES   9/27 - 9/29 2010   
#2  19.06 INCHES   9/14 - 9/16 1999 (HURRICANE FLOYD)  
#3  17.71 INCHES   9/15 - 9/17 1999 (HURRICANE FLOYD)   
#4  14.73 INCHES   9/13 - 9/15 1999 (HURRICANE FLOYD)   
#5  13.44 INCHES   9/11 - 9/13 1984 (HURRICANE DIANA)  
  
4-DAY ALL-TIME RECORDS...  
#1  20.25 INCHES   9/26 - 9/29 2010   
#2  19.06 INCHES   9/14 - 9/17 1999 (HURRICANE FLOYD)  
#2  19.06 INCHES   9/13 - 9/16 1999 (HURRICANE FLOYD)  
#4  17.71 INCHES   9/15 - 9/18 1999 (HURRICANE FLOYD)  
#5  14.73 INCHES   9/12 - 9/15 1999 (HURRICANE FLOYD)  
  
5-DAY ALL-TIME RECORDS...  
#1  20.66 INCHES   9/26 - 9/29 2010 (ONGOING EVENT THROUGH 720 AM...)  
#2  19.06 INCHES   9/14 - 9/18 1999 (HURRICANE FLOYD)  
#2  19.06 INCHES   9/13 - 9/17 1999 (HURRICANE FLOYD)  
#2  19.06 INCHES   9/12 - 9/16 1999 (HURRICANE FLOYD)  
#5  17.71 INCHES   9/15 - 9/19 1999 (HURRICANE FLOYD)  
  
SEPTEMBER MONTHLY RAINFALL RECORDS...  
#1  23.41 INCHES   1999  (HURRICANES DENNIS & FLOYD)  
#2  20.84 INCHES   2010  (ONGOING EVENT THROUGH 720 AM...)  
#3  20.10 INCHES   1877  ("HURRICANE FOUR")  
#4  18.94 INCHES   1984  (HURRICANE DIANA)  
#5  16.93 INCHES   1924  ("HURRICANE FIVE" AND "TROP STORM EIGHT")