Central States VHF Society Proceedings

The May 1998 Tropo "Openings of the Decade"

By Jon K. Jones, MD. N0JK

Several near record breaking tropo openings occurred from the Midwest across the South and southeast parts of the country into Florida, Mexico and even Cuba. These openings were noteworthy for their duration and extreme distances covered.

May 8 Tropo

The first major opening occurred on May 8. This tropo opening extended from Florida and Cuba west along the Gulf Coast into Texas. CO2OJ in Havana, Cuba. Worked many stations along the Gulf Coast from FL, AL, MS, LA and Texas. Stations as far West as WD5DJT EM12 W5VAS EM00 and KI5GF EL09 were worked by CO2OJ.

"Fantastic tropo 2m opening last night (8/5/98) 0100UTC and today early morning, 1100 UTC on. In the morning worked stations in S.Florida ( of course!! ) and K5EMD, EM30; KE4YYD, EL79, W5BK, EM11; WD5DJT, EM12; EM00; W5VAS, EM60; WD4SBV, EM61 and K5VH,( thanks for your help Tom!! )

Best DX was XE2OR on DL98 ( some kind of record?? ), (1850 km) new grid and country for me from my qth. Other stations worked K5IUA, w5AAW AND WB5PWG on EL29; W5VY, W5WC and KI5GF on EL09. This last station was the stronger I heard, a 59+++ signal all the morning. At 1400 UTC I turned off the rig. ( my boss like ham radio but ....

As information I may say that yesterday evening the S. Florida TV Channels were as strong as locals!! and we were talking in 2m FM in Habana with stations on Las Tunas, about 400 Kms east, and Miami, at the same time.

Wonderful opening, just a hard line across the Gulf of Mexico....HI"

73 and CUL, Oscar, co2oj, EL83

May 10 Tropo

HR6OGS on Roatan Island off the north coast of Hounduras was making it int the New Port Richey Florida 146.640 MHz 2 meter repeater on May 10. This station was worked by WP4MWK/W4.

May 14 Tropo

As great as the May 8th opening was, it was far less extensive than the big opening that occurred on May 14.

SMOKE FROM MEXICO SPREADING INTO U.S.

GALVESTON, Texas - There's no end in sight for the intensifying bank of smoke that wafted farther over the southern United States on Thursday, irritating eyes and leaving millions of people under dingy skies.

Kevin Darmofal, a meteorologist with the National Weather Service in Wichita, said "we are getting some effect from the fires in Mexico and Central America, probably, but it is doesn't appear to be extensive," he said. Published on 05/15/98, THE WICHITA EAGLE

Kevin apparently wasn't talking about the great tropo opening that would occur May 14. On May 14 utc tropo developed across the Midwest extending down into south Texas, Mexico and east into Florida. A massive strong opening was reported by K5IUA in EL29 at 0157 utc north to SD, northeast to TN and east to FL. Conditions improved after sunset and signals built. At 0255 W7XU in SD worked W5UWB south Texas on 2M. N0KQY in DM98 began worked stations in the Florida panhandle at 0312 utc. Then a few minutes later Gary worked W4LAF in EL87. Gary notes QSOs with "WB2QLP in EL96 at 3:23... DM98gk to EL96de figures out to 1424.3 miles / 2292.1 km. and was my best distance. Then I had WA4LOX in EL87sk at 1333 miles at 3:25." Gary did not work any FL stations above 2 meters, though he heard WD4SBV on 432. The FL stations faded out for him around 0330. W0OHU EN34 and KB0PYO EN24 worked W5UWB in EL17 on 2M for some nice 1900 km contacts.

N0JK noticed 2M tropo spots appearing on the "DX Summit" Web Cluster May 14 while trying to work 3B7RF on 20M, a HF Dxpedition on St. Brandon Island. I live in a C C & R "no outside antenna" restricted sub-division. I usually operate VHF/UHF portable - either from EM18 or a hospital roof top here in Wichita. I had no antennas or gear set up at the hospital. I packed my TR-751A and 4 el yagi and a mast into a small car, and drove about a mile east of my home to a hill with a good horizon shot south and east. Maybe I could work some of the tropo if conditions were as good as the internet cluster spots indicated.

Around 0340 utc N0JK EM17 worked W5UWB EL17 with 10 w and 4 element yagi on 2M. John had good signal on SSB. He mentioned he worked N0LL earlier on 1296. N0LL EM09 worked W5UWB and K5IUA on 1296. I told him I would go home and get my 1296 gear and try a contact on that band. We set 0400 as a sked time. I went home - all the 1296 stuff was stored in boxes in the basement. By the time everything was out to the car it was 0400 utc. I tried listening for John from the driveway - on 1296 MHz but nil. I gave up frustrated - then thought - well might as well go back out to the hill and at least tell W5UWB what happened and see if I can work anything else on 2M.

At 0400 utc CO2OJ suddenly appeared on 144.200 and began working stateside VHF operators. Oscar worked KB4VHW and KD4AKE in EM60. Oscar began working into the Midwest. I had Q5 copy on CO2OJ on 144.2! K5CM and N5KW in EM25 at 0405 utc were first in the log, then W0RRY in EM26 at 0407.

VHF Prop Web site

May 14 02:40 CO2OJ 5x5 on 144.200 running 2 watts into EM60 de N7JJS/4

May 14 04:09 CO2OJ working K5CM in EM25 Oklahoma on 144.200 de N7JJS/4

DX Summit Web site

W2GFF 144200.0 CO2OJ wkg into Midwest 0421 14 May N0JK-@ 144200.0 CO2OJ Wked with 10 w, 4 el yagi!! 0442 14 May (posted after going home) The pileup thinned out then W0EKZ worked Oscar at 0410 utc and N0JK at 0418 utc. N0LIE EM27 was heard calling CO2OJ around 0425 utc but Oscar was fading out.

CO2OJ's 2 meter signal had two definite peaks into KS - around 0410 and 0418 utc. After the second peak he faded out and was not heard again. Oscar was heard briefly by Gary, N0KQY DM98 during this period. Gary "heard him working K5CM with a good Q5 copy. I think that was around the 4:10 area. Then at 4:20 I heard him again when he say CO2OJ Echo Lima 83.

" The propagation from Cuba into the Midwest was confined to a narrow "pipeline" running northwest from Cuba crossing into Mississippi at EL50 then on to eastern Oklahoma and south central Kansas. Stations in EM60 were hearing CO2OJ work the Midwest, but did not hear the Midwest stations. In turn no AL or FL stations were heard while CO2OJ was audible, which was probably fortunate as CO2OJ was operating on the 144.200 call frequency and would have been covered up by stronger stations. CO2OJ observed that "There were stations on Oklahoma that I worked perfectly and Frank W4AMJ EL86 didn't even hear.

" If you worked CO2OJ on 2M during May, you can check Oscar's interactive log at:

http://www.infocom.etecsa.cu/cgi-bin/frc/frcuba.htm

You can download an "electronic QSL" from the SK0UX Web server for CO2OJ.

Distances worked by CO2OJ on 144 MHz into the Midwest May 14:

The contacts by W0EKZ and N0JK may be the first 2 meter contacts ever made between Kansas and Cuba! Bud, W0EKZ has the honor of making the first.

Distance from CO2OJ EL83TD to N0KQY DM98gk 1541.8 miles 2481.1 km

If Gary N0KQY had worked CO2OJ they would have broke the 2 Meter Tropo (A) record. The current record is VP5D FL31UT > W1JSM FN43NC 2365 km May 10, 1988 (Claimed North American DX Records compiled by Al Ward, W5LUA) Other possible records that could have been set during this opening: 432 Tropo (C) current record is KM1H FN42hr > WB4MJE EL94hq 2204 km Dec 16, 1992 N0KQY DM98gk > WB2QLP EL96de is 2292 km - a 432 QSO would have broke the record!

1296 Tropo (C) current record is KD5RO EM13pa > WB3CZG FN21ax 2071 km Nov. 29, 1986 N0KQY DM98gk to K2RTH EL95tq is 2430.95 km - this station has 1296 MHz and was active!

N0KQY in DM98 is well situated to set some new records along the tropo path to FL and Cuba.

There was also strong tropo south into Mexico. W0EKZ worked XE2OR on 2 meters around 0300 utc.

Fernando Garcia, a TV DXer in DL95vp Monterrey, Mexico reported great tropo even later that night.

"The best 1000+ miles tropo opening this time was this morning (Thursday) to north up to Omaha, Nebraska (channels 15 and 42) snow free at 1 AM CDT and Iowa Public Television channels 21 and 36 close to snow free at 3 AM, my local station on channel 22 was off (rare) for about two hours allowing the best log of the night KDIN-21 Fort Dodge (central Iowa) 1230 miles. Many other stations from Oklahoma, Kansas, west Arkansas and west Missouri were logged.

" Imagine the potential microwave contacts suggested by Mr. Garcia's TV loggings!

As dawn approached in the Midwest the tropo was moving east though several Texas stations south to EM00 were heard in EM17. But at 12:13 N7JJS/4 EM60 into EN13 on 144.210 de W7XU. The tropo picked up again that evening.

May 15 after 0320 utc, CO2OJ was "hanging out on 144.250" and working many stations including AL, FL, MS, OK and TX. Oscar also made a nice contact with K5UR EM35 AR, who was alerted to CO2OJ by W2GFF "I did get K5UR EM35 to go up on 144.250 and they made it OK at about 0415 Z.

" Strong tropo continued along the Gulf Coast and enhancement began along the eastern seaboard. As dawn approached on May 15 intense tropo formed along the eastern seaboard from New England and the Maritime Provinces in Canada to Florida under a high pressure region. At 11:35 W4WHN EL94 was 5/7 INTO FN41 W1SN on 2M. W1LP in FN41sr worked many FL stations and his best DX - CO2OJ on 2M! The tropo was so intense Clint was audible in FL running 1 watt on 2M! Using the Internet, Clint e-mailed Oscar during the opening to see if he would go home from work to try 2 meters. Oscar went home, turned on his radio and they worked! CO2OJ EL83TD > W1LP FN41SR is 2344.22 km (1465.136 miles) Only 21 km short of the existing record. Again, close..... if any of the stations north of Clint such as VE9PA or W1ALS had worked CO2OJ a new Tropo (A) record would have been set May 15.

Oscar posted the following "resume" of contacts he made May 15 utc to the VHF Reflector:

"worked stations in EL09(1), EL29(2), EL49(1) EL50(1), EL87(1), EM51(1), EM59(1), EM00(1), EM10(1), EM11(1), EM25(1), EM31(1) EM32(1), EM35(1) and FN41(2).

" He also listed "statistics" of the May 14 - 15 tropo opening that are interesting.

"Here are some "numbers" of the "one in ten years" week of tropo on 2m, from and to Habana > CO2OJ EL83TD:

CO2OJ's station: 100w and 9 elem homebrew yagui, 12 feet over the roof.

65 QSO's x 36 Grids worked

Oscar had QRM from the pileups and interference from the second harmonic of a local 72 MHz broadcast station on 2 meters.

Due to the strength of the tropo inversions stations running low power and simple antennas did amazingly well. Dick, W2GFF in EM60 AL observed that "These band conditions were amazing. I am running 25 watts to an Oscar satellite antenna system on 2 meters, and am in a poor location in a gully with tall trees, and still worked a bunch of OK, AR, MO, TX, LA, TN, FL, CO2OJ, and N0KQY DM98. Guess I must move to a better QTH." N0JK EM17 worked CO2OJ with a TR-751A and a 4 el yagi. CO2OJ made tropo QSOs earlier in the evening running only 2 watts.

HR6OGS on Roatan Island off the north coast of Hounduras was making it into the New Port Richey 146.640 MHz 2 meter repeater on May 10. W3EP notes that while the distance was about 1,100 km and not remarkable, it did suggest that much longer CW/SSB QSOs were possible across the Gulf of Mexico and Caribbean.

Analysis of the May 14 - 15 opening - Was it due to El Nino?

Do you thing this week of tropo has some relation with "el Niño"?? That is something to think and discuss about. - Oscar, co2oj, el83 May 14, 1998

Wave Cyclone and High Pressure system

Emil Pocock noted in "The World Above 50 MHz" Aug 1998 that a sprawling dome of high pressure settled over the southeast US for much of the month of May. It was trapped in this Position by the Jet Stream. This is called a "blocking High." It is more common over the southeast during the late summer and early fall. Emil notes it is not clear why a blocking high pressue system sat so long over the southeast during May. Some of this weather was "clearly triggered by the regional effects of El Nino- Southern Oscillation warming the eastern Pacific Ocean. "During a warm episode winter, mid-latitude low pressure systems tend to be more vigorous than normal in the region of the Gulf of Alaska. These systems pump abnormally warm air into western Canada, Alaska and the extreme northern portion of the contiguous United States. Storms also tend to be more vigorous in the Gulf of Mexico and along the southeast coast of the United States resulting in wetter than normal conditions in that region." - NOAA.

But it is not so evident that May's blocking high pressure system can also be linked directly to El Nino. Global Weather is infinitely complicated - Chaos Theory - and it may be tempting to attribute the tropo ducting to El Nino. Most meterologist are reluctant about jumping to that conclusion.

I believe the tropospheric propagation on May 14 - 15 was a combination of two modes. Across the Gulf of Mexico and southeast US the high pressure system was in place. Tropo contacts had been made by subsidence inversions along the Gulf Coast from Florida to Texas.

A large wave cyclone system moved into the Midwest the afternoon of May 13. It pivoted around a low pressure north of Minnesota in southern Canada. The high pressure over the Gulf of Mexico helped draw up mild humid gulf air. Mild moist air flowed steadily northward from Mexico, Texas and the Gulf of Mexico near the surface ahead of the cold front The air was foggy with "smoke smog" from the fires in Mexico. The dew point was over 70! This is very humid!

GALVESTON, Texas - There's no end in sight for the intensifying bank of smoke that wafted farther over the southern United States on Thursday, irritating eyes and leaving millions of people under dingy skies.

Fires in southern Mexico and Central America have been sending smoke up the Gulf Coast for more than a week, sheathing the Gulf of Mexico in a gloomy fog. - Wichita Eagle

Dry fast moving warm air began sweeping down off the east slope of the Rocky Mountains at an altitude of around 5,000 feet associated with the jet stream. Where these winds intersected, with mild and moist below and very warm and dry above, it created a strong and relatively flat inversion at altitudes of about 3,000 feet. Upper air profiles confirmed this.

Subsidence from the high pressure system helped stabilize the inversion layer and extended the tropo further. Usually the longest range tropo contacts occurring with a Wave Cyclone are in a southwest to northeast path. The longest range QSOs May 14 utc instead occurred northwest to southeast from KS and OK to Cuba and Florida. Signals propagated by the Wave Cyclone inversion traveled southeast from the midwest until they reached the subsidence inversion under the high pressure system and thus continued on to Florida and Cuba. The transient periods that Florida and Cuba made tropo contacts into the midwest is consistent with this type of fragile link. The signals from Florida and Cuba to the midwest were often weak with QSB. The signals propagated by the wave cyclone or under the high pressure dome instead were often quite strong and steady.

The UHF television reception reports by Mr. Garcia from Monterrey show the inversion from the wave cyclone was stable for hours at a time with strong signals received to the northeast from Iowa and Nebraska. However, Florida was worked only for a 30 minute period before 0400z and about an hour after 0430z. CO2OJ was able to work into the midwest only about 20 minutes.

The next morning the wave cyclone moved east. The high pressure region expanded over the eastern seaboard from New Engalnd and the Maritime provinces of Canada down to Florida. Now the best DX contacts were in the southwest to northeast direction as is more common with a high pressure system. "The path from New England to Florida was notable because W1LP on Cape Cod had great conditions, but stations even a bit inland from the ocean (W3EP is only 25 miles from the coast) heard considerably less. Perhaps they were just on the western edge of the duct or the duct (for some reason) was much stronger over the ocean." - W3EP

May 22 - 24

Widespread tropo across the southern states and extended into the midwest occurred again.

WICHITA AREA GETTING A HAZING METEOROLOGISTS SAY WE'LL BE BLANKETED AS LONG AS RURAL MEXICO BURNS AND PRESENT WEATHER PATTERNS CONTINUE

"Get ready for the hazy, crazy, lazy days of summer. As long as fires continue burning in Mexico, Wichita will continue to be blanketed in the haze that is giving days an opaque quality." Published on 05/23/98, THE WICHITA EAGLE

The tropo appeared in the morning of May 22 when N0KQY DM98 found 2 meters open into Florida around 1200 utc. During the day strong humid southerly winds were present across the midwest. Bud, W0EKZ noted strong co-channel interference on all VHF TV channels in the afternoon but nothing on 2 meters. At sunset activity appeared on 2 meters. N0JK EM17 was up and running at 0150 utc on 2 meters from his portable location on a hospital roof top in Wichita, KS running 150 watts and a Jr. Boomer yagi. Strong humid "smoke smog" winds were noted from the south.

W0EKZ made QSOs with some of the same stations as well on 2. Signal for the most part was not strong, around 53 to 55 for most, but N4RFN and KT4AL were 57 to 59. WD4SBV was 59+. CO2OJ was not heard this time. Stations further southeast of Wichita seemed to be in the tropo better, EM27 and EM26 were giving and receiving 59 reports from FL. XE2OR was worked by stations in LA, not heard in EM17.

The next morning the tropo was gone in Wichita as the weather system moved southeast. But KC7ICM in EM04 found the band open.

KD4ESV 22/05/98 10:27 SSB 144.200 59 55 RADENTON FL EL87
KT4AL 22/05/98 11:14 SSB 144.150 59 55 FL EL87
W0VHF 22/05/98 11:35 SSB 144.170 59 33 EL87

May 22 1100 902 MHz N5WS EL09ra ; K0VXM EL98pi 902 MHz

The contact between N5WS and K0VXM is 1747 km, and may be a new terrestrial record for North America on this band.

Conditions would continue to improve for stations in southern Okalahoma and Texas over the next 24 hours.

That evening, tropo started along the Gulf Coast between FL and TX. John, W4UE in EM90 worked:

03:14 KC5FMT EL29 144.200
03:15 N5WS EL09 222.100

But the next morning the real action started. At dawn super-refractive tropo intensified between Florida and Georgia to Oklahoma and Texas.

John Moore, W4UE EM90 was in the hot spot as he cleaned up 2 meters through 1296 from Florida

K2RTH in Miami, FL did well too. He notes "Stations worked or heard included:

144 Mhz: W3XO EM00, WC5E EM02, N5HJM EM02(heard), K5ACR EM04, KC7ICM EM04, KK6IT EM11, W5BK EM11, WT7D/5 EM12, N5TIF EM12, K5UGM EM12, WA5TKU EM13, WB5DGR EM20, N0EOQ EM24, K5SW EM25, KB5UXO EM43, KJ5SF EM45, N4JQQ EM55, K5AND EM74, W4UE EM90.

Equipment on 144 Mhz: 140 Watt brick feeding my four 17 element M2 yagi EME antenna at a mean height of 18 feet. The bottom two antennas at 12 feet look into neighbors house. Height is not important in South Florida, by W4KXY who was hearing Mexico from EM84(SW to NE opening) at the same time band in SE Florida was open to the North, NW, and West but not to Mexico(SW)." The reason this is an issue is that "unlike ionospheric skip, all stations within a tropo ducting area normally hear each other." This is because an inversion continuously refracts radio waves back toward the earth over paths it covers completely. This didn't seem to be happening with this tropo opening and K2RTH was puzzled:

"One would then guess a ground level duct except grids were either very weak or missing from EL29, EL39, EL49 in SE Florida, while grids further to NW and W were 59+ here, indicating that the duct was passing over these grids from SE Florida. EL29, EL39,; EL49 were however present in propagation from NE Georgia"

What was going on here, and also on May 14 when W2GFF heard CO2OJ, the midwest could hear CO2OJ, but W2GFF couldn't hear the midwest? Does the weather map for May 22 have any answers?

The map for May 22 shows a long wave cyclone running from a low pressure centered just west of Wichita, KS going east. High pressure is located over Havana, Cuba. A cold front is moving east over New Mexico. The wave cyclone appears to be the primary weather system responsible for the tropo May 22 - the high may have been involved with some of the longer haul paths May 22 around 0400 utc, but was too far out in the Gulf to have created inversions propagating signals along the Gulf coast. The high did help strengthen the surface flow of winds from the south.

As for the selective propagation - perhaps the duct didn't brings signals from Florida all the way to the ground at the midpoint in EL49 - but did in EM12 and 13. The tropo signals passed overhead then were refracted to cover the additional distance. Some very puzzling and unusual tropo propagation. What about this fall?? Current Climatic studies suggest that we are now entering the, La Niña phase of the ENSO Oscillation.

References
  1. "The Weather that Brings Vhf DX", Emil Pocock, W3EP QST May 1983
  2. Three-dimensional complexity" Chris Cappella and Jack Williams, Flight Training, June, 1998.

  3. "Claimed North American Distance Records" "The World Above 50 MHz" QST May 1998, pp. 86.
  4. Tropo maps for May 14 and May 22, The "Rochester VHF Group's website": http://VHFGroupers.greeceny.com
  5. Weather Maps, The Weather Channel Web Site,