Dudley learned that Eureka is one of the nation's most notoriously foggy areas. In fact, it was one place where instrument approaches were baselined a half-century ago. During the summer, the fog often rolls in at around 4 p.m. - at around 15 knots! So, if the weather permitted, getting there by mid-afternoon was more than just a good idea.
As he plotted his route on the Klamath Falls sectional, several things became apparent. First, there weren't many radio navaids along his route, but the Pacific Ocean would make a handy substitute.
Second, two navaids near his destination - Crescent City VORTAC and Arcata VOR-DME - transmitted transcribed weather broadcasts (TWEB). Looking in Aviation Weather Services, Advisory Circular 00-45D, he saw that he'd fly right along TWEB route 374. Combined with flight following and Flight Watch, Dudley would get what amounted to a continuously broadcast weather briefing!
Third, he had to decide whether to fly at a relatively low altitude, where he'd get a better view of the majestic cliffs and giant redwoods - or higher, where he'd be assured of more options in the event of a mechanical problem. Although he wouldn't be flying over the open ocean, the rocky coast didn't offer the Midwest's abundance of emergency landing sites.
Finally, his initial magnetic course would be just west of south, so he'd cruise at an even thousand foot altitude plus 500 feet, but most of the flight would be slightly eastward, and he'd need to be either a thousand feet higher or lower.
After Dudley plugged his laptop computer into the phone line, he mulled over the satellite photo he downloaded from www.cnn.com/WEATHER/ NAmerica. He also downloaded the composite radar picture. It looked like the flight might go, but the clouds off the coast worried him.
Next Dudley tapped into DUATS and downloaded the following: SFOC FA 261145 SYNOPSIS VALID UNTIL 270600 SFC...CDFNT CNTRL BC CSTLN SSWWD WELL OFF THE PAC NW CST WK MOV EWD RCHG SRN VRISL-SRN OR CSTL WTRS BY 18Z AND FM SW ALTA-SW BY 06Z
The 1145 Zulu (3:45 a.m. local time) synopsis on the 26th said there was a cold front from the central British Columbia coastline that angled south-southwestward and was well off the Pacific Northwest coastline. The front was moving eastward and should reach southern Vancouver Island, B.C. or coastal waters by 10 a.m. and from southwest Alberta by 10 p.m.
OR CASCDS WWD RMNDR AREA...BKN CI. 18-21Z SCT050 BKN100. TOPS FL180. WDLY SCT -SHRA CSTLN. OTLK...MVFR CIG RA CSTLN..VFR SHRA ELSW.
For the Oregon coast, there would be broken ceilings and from 10 a.m. to 1 p.m. One could expect scattered clouds at 5,000 feet and broken clouds at 10,000 feet, with cloud tops to Flight Level 180 (18,000 feet). There would be widely scattered light rain showers along the coastline. The outlook forecast marginal VFR ceilings in rain along the coastline and VFR conditions with rain showers in the rest of the area.
CSTL WTRS NRN CA...SCT020 SCT-BKN CI. 16-19Z SCT030 BKN CI. OTLK...VFR.
For the coastal waters of Northern California, there should be scattered clouds at 2,000 feet and a scattered-to-broken ceiling. Between 8 and 11 a.m. there should be scattered clouds at 3,000 feet and a broken ceiling. The outlook was for VFR conditions.
Dudley realized that these were generalized statements for wide areas - and that these portents of gloom and doom were already more than six hours old (It was now past 10 a.m.) Happily, there were no SIGMETs or Weather Advisories for his route, and only an AIRMET for a freezing level above 10,000 feet.
Eagerly jumping to the METARs for North Bend and Brookings, Oregon, as well as Crescent City and Arcata/ Eureka, California, Dudley saw some of those dark clouds lifting. North Bend's automated weather observation station, which can't discriminate between different types of precipitation, (AO1) reported METAR KOTH 261755Z 12009KT 10SM SCT075 11/06 A3004 RMK AO1 SLP173 10117 20072 - a nine knot wind from 120 degrees, 10 statute miles visibility, scattered clouds at 7,500 feet, a cool 11?C (54?F) with a 6?C (43?F) dewpoint, and an altimeter setting 30.04 inches. The remarks reported a sea-level pressure of 1017.3 hectopascals (hPa, or millibars, or 30.06 inHg), an 11.7?C six-hour maximum temperature and a 7.2?C six-hour minimum temperature.
Brookings (about the half-way point) reported METAR K4BK 261746Z 22004KT 60SM FEW150 BKN200 12/06 RMK SLP177 NOSPECI T01210062 10121 20041 53007 - a four-knot wind from 220 degrees, 60 miles visibility, a few clouds at 15,000 feet, a ceiling of broken clouds at 20,000 feet, and a temperature/dewpoint similar to North Bend. In the remarks section, the sea-level pressure was 1017.7 hPa (30.05 inHg), there were no special observations, the precise temperature and dewpoint were 12.1?C and 6.2?C respectively, and the six-hour temperature maximum/minimum values were 12.1?C and 4.1?C.
Dudley couldn't find a good explanation for the last cryptic group in the METAR - 53007 - in Aviation Weather Services, Advisory Circular 00-45D. Being a curious guy, after his flight he found the answer in the METAR/TAF training files at the FAA Academy web site (www.ama500jccbi. gov/at/files.htm). That last group was a three-hour barometric pressure trend. It was higher than three hours ago, and it was decreasing or steady then increasing, or increasing then increasing more rapidly (the "3") by 0.7 hPa.
About 20 miles farther south, Crescent City reported METAR KCEC 261750Z 18010KT 20SM FEW150 BKN200 14/04 A3009 RMK ACSL N SLP190 - a 10-knot wind from 180 degrees, 20 miles visibility, a few clouds at 15,000 feet and a ceiling of broken clouds at 20,000 feet. The temperature and dewpoint were 14?C (57?F) and 4?C (39?F), and the altimeter setting was 30.09. The remarks indicated alto cumulus standing lenticular clouds to the north (don't fly under those!), and sea level pressure 1019.0 hPa (30.09 inHg).
Finally, at Dudley's destination, Eureka reported METAR KACV 261755Z 17006KT 30SM SKC 14/06 A3006 RMK SLP180 T0144006010144 20050 51010 - a six-knot wind from 170 degrees, 30 miles visibility, a clear sky, and a good temperature/dewpoint spread. In the remarks, after the sea level pressure and accurate temperatures, was the six-hour maximum and minimum temperatures - 14.4?C and 5.0?C. The three-hour pressure group said the barometer was higher than three hours ago, and increasing then steady, or increasing then increasing more slowly (the "1") by 1.0 hPa.
The reported weather looked promising, but to make a more informed go/no-do decision, Dudley studied the terminal forecasts next. They were fairly recent (9:30 a.m. local), and fairly good.
The prediction for North Bend was TAF KOTH 261730Z 271818 13009KT P6SM SCT090 BKN200 TEMPO 1822 BKN090 FM2200 15010KT P6SM BKN070 OVC150 PROB30 0010 -SHRA BKN040. At 22Z (2 p.m.), the time Dudley was hoping to take off from North Bend Municipal, the wind would be closing in on 150 degrees true at 10 knots - almost right down Runway 13. The visibility was expected to stay greater than six miles, with a scattered layer at 9,000 feet and a ceiling of broken clouds 20,000 feet. For an hour or so sometime between 10 a.m. and 2 p.m. that scattered layer might temporarily become broken clouds. From 2 p.m. on, there would be a ceiling of broken clouds at 7,000 feet, an overcast layer at 15,000 feet, and there was a 30 percent chance of light rain showers and a ceiling of broken clouds at 4,000 feet.
Crescent City predicted TAF KCEC 261730Z 261818 12005KT P6SM SCT150 BKN200 FM2000 20007KT P6SM BKN100 OVC200 FM2300 20008KT P6SM BKN090 TEMPO 2301 -SHRA. At the start of the forecast period, there would be scattered clouds at 15,000 feet, a ceiling of broken clouds at 20,000 feet, and more than six miles visibility. From noon on, there would be a broken ceiling at 10,000 feet. If his departure was delayed, at 3 p.m. Dudley should expect a broken ceiling of clouds at 9,000 feet and light rain showers up until 5 p.m.
The prediction for Dudley's destination said TAF KACV 261730Z 261818 23005KT P6SM SCT200 FM2200 24008KT P6SM SCT150 BKN250 BECMG 0204 SCT050 BKN120 OVC200. Eureka was expected to start with five knot winds at 230 degrees true, more than six miles visibility, and scattered clouds at 20,000 feet. By 2 p.m. the winds might increase to eight knots and shift to 240 true, with 15,000 scattered and 25,000 broken. If he somehow managed not to arrive until 6 p.m. (02Z), he might have to deal with a 5,000 foot scattered layer.
Things were looking up! It was looking more like a GO for this trip. The ceilings and visibility met Dudley's personal minimums, the temperature/dewpoint spreads suggested no surprises, and the chances of precipitation were small. Even the wind aloft wasn't that bad. Because of the ceilings he didn't check the wind any higher than 6,000 feet, which was from the southwest at 17 knots. At 3,000 feet the wind dropped to 14 knots.
Several of the NOTAMs caught Dudley's attention. He saw several things of interest regarding his destination. There was a new frequency for Runway 14/32's pilot-controlled approach lights, a new common traffic advisory frequency (CTAF), and the DME was out of service. In addition, the FAA decommissioned the flight service station (and remote communications outlet) about a month earlier.
Dudley decided to go. After takeoff he'd cruise at 4,500 feet, and then continue on at 3,500 feet when he changed course at Cape Blanco (the western-most point in the continental U.S.). That way he would stay well below any possibly lowering cloud layers.
Running the numbers, he figured on a bit under an hour and a half en route. He called in his flight plan and was on his way. When he got to the airport at noon, the visibility, winds, and clouds followed the script - they were just what they had been forecast to be.
Dudley took off and opened his flight plan at 12:55 p.m. The flight was glorious! When he landed at Eureka, there was a scattered layer at 7,000 feet, light four-knot winds, and 20-mile visibility. As he left the airport, he knew he had been fortunate. As always, he wondered how it would go, the next time...
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