It was very disappointing to see AOPA push out such a blatant sensationalized Tweet and article after the recent Aviator Showcase in Fort Worth, Texas which I attended. To say "A dire weather forecast kept few away..." and "As they often are, the forecast was wrong..." is crass and irresponsible to the general aviation community they serve. It strongly suggests and promulgates the fact that pilots should never trust forecasts since they are almost always wrong. In all actuality, the weather was a bit worse than forecast during part of the morning so it's hard to know what forecast they were using to suggest the forecast was so dire and so wrong.
No matter how good the meteorologist, forecasts are never going to be perfect. Even so, these forecasts can still be incredibly useful. Let's take a look at the weather and the forecast for this October day.
If they were using the official aviation forecast for Fort Worth Alliance Airport (KFTW), they would have looked at the Terminal Aerodrome Forecast (TAF). So on the previous afternoon, for pilots contemplating an arrival the next the morning they would have seen the TAF issued at 3:53 PM on September 30 (shown above). The end of this TAF covered the weather through the morning on October 1st. The forecast group in red included southeast winds at 5 knots with better than 6 miles visibility and a marginal VFR ceiling that was broken at 1500 feet. It was expected to be a cloudy morning with no precipitation.
The TAF above was issued at 6:25 PM on the evening prior to the event that included the same MVFR ceiling forecast with light southeast winds from 4 AM (0900Z) through 7 PM (0000Z, October 2nd) that basically covered the entire event. Certainly this is not a "dire" forecast. From a planning perspective, it's not a great forecast for VFR flight, but certainly a comfortable IFR flight for most proficient instrument rated pilots.
The TAF above was issued in the overnight hours and later amended below at 4:35 AM. The TAF below would have likely been the forecast available prior to departure in the morning on October 1st. The primary addition was to make that broken MVFR deck a temporary condition between 8 AM and 11 PM with good VFR weather otherwise for the remainder of the day. The other addition was the potential for thunderstorms in the vicinity (VCTS) beginning at 3:00 PM through 10:00 PM.
Is that the "dire" forecast they are referring to? Maybe, but let's take a look at what really occurred at the airport. First, let's look at the VCTS forecast. During the entire event, the airport did not report any thunderstorms or thunderstorms in the vicinity, but it did report rain between 11:10 AM and 11:24 AM as you can see from the remarks below. Certainly not a washout event.
KFTW 011653Z VRB03KT 10SM BKN070 23/19 A3007 RMK AO2 RAB10E24 SLP175=
By the afternoon, convection started to develop in the vicinity of the airport. There were a few thunderstorms in the Dallas/Fort Worth area, however, most of this was simply rain showers which are deep, moist convection without lightning. The radar mosaic below valid at 1:35 PM certainly shows those showers in the vicinity of the Fort Worth Alliance Airport that is circled in red.
The ceiling heights at the airport turned out to be MVFR to VFR most of the morning with light winds and good visibility. The SCT015 and BKN080 forecast for the morning turned out to be pretty darn close to the observations. Minor differences here, but the weather was closer to SCT/BKN023 and OVC080. While not exact, it certainly should not be labeled as a "wrong" forecast.
At 9 AM, the forecast went off the rails a bit with a broken IFR ceiling of 900 feet. That lasted for a little over an hour. Yes, the forecast was for a broken MVFR ceiling at 1,500 feet when in fact it ended up with a broken IFR ceiling at 900 feet. For the remainder of the day the ceiling wasn't a factor. But, the forecast was actually a bit more optimistic than what actually occurred...so it's hard to understand the AOPA comment of a "dire" forecast.
Most pilots are weatherwise, but some are otherwise™
Dr. Scott Dennstaedt
Weather Systems Engineer
CFI & former NWS meteorologist