October 2025 Discussion and Obs

[wdrag]

Any TC rain hits?   Any early season interior high terrain snow acc late in the month?  Do we experience above normal rainfall for October?  

[donsutherland1]

 

[LibertyBell]

47 minutes ago, donsutherland1 said:

Don how did EWR go from the hottest September on record in September 1891 to the coldest October on record in October 1891?  Both are way out of line with NYC lol.

[donsutherland1]

18 minutes ago, LibertyBell said:

Don how did EWR go from the hottest September on record in September 1891 to the coldest October on record in October 1891?  Both are way out of line with NYC lol.

Missing dates. I have redone the file. I had forgotten to exclude months with missing days.

 

[donsutherland1]

September 16-30, 2025 is on track to finish with 0.47" rainfall for Central Park. Since 1869, there have been 25 cases with 0.50" or less rainfall during the second half of September. Among those cases, 60% went on to have a drier than normal October while 40% went on to have a wetter than normal October.

The latest CFSv2 monthly forecast shows a drier to much drier than normal October:

The latest ECMWF weeklies also show a drier than normal start to October:

 

CPC's 6-10-day precipitation forecast also favors drier than normal conditions:

However, its monthly forecast from September 18th indicates equal chances of above or below normal precipitation. 

Finally, of the 8 years with mean temperatures of 70° or above during the second half of September coupled with < 1.00" rainfall, 75% were followed by a drier than normal October. The two exceptions were 2005 and 2019.

All said, the odds lean toward a drier than normal October, but that isn't cast in stone.