A lesson learned in this first week of forecasting is that forecast timing is everything.

The perfect example was the  first day of the forecast period and the missed precipitation forecast. If I had a better feel and knowledge of the timing of the arrival of the departure of the precipitation I would have had much better results for the first day's forecast.

Below is a chart of the expected precipitation from the 12Z NGM and ETA FOUS forecasts for February 22nd's forecast period highlighted in bright green and the 6 hour period immediately following it in bright red. As you can see the forecast for the period is for anywhere from 0.19" to 0.89" of precipitation. I chose to go with a lower average number of 0.30" of precipitation. The actual amount received was in fact only 0.13" as shown by the METARs below, even farther below than my lowered estimate.

Looking at the next precipitation total from 0853Z that day we can see that the site in fact received another 0.14" of precipitation in the  3 hours following the end of the forecast period, bringing the total to 0.27", or very close to my predicted amount of 0.30".  So had I been more careful in the timing of my precipitation forecast I may have been more accurate in the actual total.

For my first week of forecasting it was made very clear that it is critical to get not only the amounts of precipitation correct but the time of the arrival. Hopefully as the class progresses I can gain more experience in forecasting and become a better judge of the timing of the precipitation forecasts through more careful study and use of the FOUS products.
 

NGM FOUS   FOUM69 KWNO 221200 OUTPUT FROM NGM 12Z JAN 22 07 TTPTTR1R2R3 VVVLI PSDDFF HHT1T3T5 SAT//786533 -2505 220221 51020604 06000656044 01005 230210 50050304 12000515264 -0208 230413 52090204 18000505793 -1807 230514 54080305 24000587392 01607 230611 54060205 30000838480 05508 240505 55050107 36009959373 02109 220408 56060107 42010969884 04307 230705 56060208 48034969995 03610 230210 55060206

ETA/WRF FOUS   FOUS69 KWNO 221200 OUTPUT FROM NAM 12Z JAN 22 07 TTPTTR1R2R3 VVVLI PSDDFF HHT1T3T5 SAT//776335 -1506 210221 51040704 06001675637 -0707 250215 51040502 12000565453 00508 220314 51070501 18000635473 02309 250317 51060402 24003747867 06309 230319 52040502 30003778850 04010 250313 52040603 36017919766 01108 240212 56040706 42066979978 17206 240314 57040805 48082939863 -0108 240320 55040803 54033949872 -4509 260318 54050803 60020909562 02508 260217 53050401

KSAT 231753Z 03012KT 10SM -RA BKN044 OVC060 06/02 A3023 RMK AO2 SLP229 P0000 60001 T00610017 10061 20044 50008
KSAT 232353Z 01008KT 10SM BKN040 OVC050 06/01 A3020 RMK AO2 RAB2255E14 SLP220 P0000 60001 T00610011 10072 20056 53001
KSAT 240553Z 32003KT 4SM RA BR OVC039 06/04 A3026 RMK AO2 SLP242 P0006 60011 T00560039 10067 20050 400720044 53007

KSAT 240853Z 34004KT 9SM -RA OVC040 05/03 
	A3024 RMK AO2 SLP234 P0001 60014 T00500033 58008

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