I was perusing QMD QPF in DESI, but see the same in the WSUP
views, for forecasts with a valid time of 12UTC Mon, Dec 11.
I realize the color curves change, but in looking at the
values around Poughkeepsie, NY, for the forecast 12-
(1.43"), 24- (2.49"), 48- (2.33"), and 72-hr
(2.20") Mean QMD QPF amounts, I was surprised to see the
48- and 72-hr amounts lower than the 24-hr Mean Amount.
Looking at the PQPF for >2" (not shown) for each at
Poughkeepsie, I see 20%, 75%, 67%, 58%, respectively for 12-,
24-, 48, and 72-hr.
Is it as simple as the membership going into the QMD Mean
calculations being different? I'm probably not thinking hard
enough, but I guess I was expecting the membership to be the
same, such that for the longer time periods, you'd have higher
Mean amounts and greater probabilities, since they each have the
same end time (12UTC Dec 11).
But, I guess somehow, when the overall valid time window is
enlarged, the uncertainty in the timing of when the precip will
fall somehow lessens the amounts/probs?
12-,
24-, 48-, and 72-hr from DESI
72-hr
from WSUP (just showing it matches the DESI view)
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