EASTERN SAUDI ARABIA, JAN. 22 -- A thick blanket of clouds continued to obscure military targets in Kuwait and southern Iraq today, causing sharp curtailment of air strikes against various targets, including Scud missile launchers used by Iraq to attack Israel and Saudi Arabia.

Planned air strikes also were cut back against Iraq's Republican Guard troops and border fortifications facing the allied forces of Operation Desert Storm.

The cloud blanket has been especially difficult for U.S. and allied warplanes flying missions along Saudi Arabia's northern border, hiding artillery and tank targets throughout the area and complicating the search farther north for the mobile launchers that Iraq has used to fire more than 20 surface-to-surface Scud missiles into Israel and Saudi Arabia.

In addition to the Scud missile launched into Israel today, six were fired at targets in Saudi Arabia. Two Scuds were knocked down by Patriot anti-missile batteries, and the other four fell harmlessly in the Saudi desert or the Persian Gulf.

"We had an air campaign planned, and we are staying with that plan as much as the weather has allowed us to do so," said Air Force Col. Erwin C. "Sandy" Sharpe, commander of the 354th Tactical Fighter Wing. "It is a little frustrating when you go up to the target area and you can't see the ground."

The 354th, based in Myrtle Beach, S.C., is composed of A-10 Thunderbolt II attack jets -- slow-flying but highly maneuverable fighter-bombers specializing in close-air support for ground troops.

No ground war has developed thus far in Desert Storm, however, and the hulking green A-10s, many with toothy grimaces painted on their noses, have been directed to fly bombing and attack missions behind Iraqi lines against isolated "soft targets" such as artillery pieces, tanks, other armored vehicles and Scud missiles.

"We need to find the targets to strike them," said Sharpe, noting that the A-10 is a "day fighter" that has no radar and must be able to see its targets in order to take them under fire.

The skies cleared in some areas of Iraq, allowing the allied forces to fly about 1,900 missions -- which have included reconnaissance flights and other activities over Saudi Arabia, as well as bombing raids -- up from 1,100 sorties flown on Monday. Military officials said more than 10,000 bombing, air support and other aerial missions have been launched since the operation began last Thursday morning.

In western and northern Iraq, skies began to clear Tuesday, permitting an intensification of both bombing and reconnaissance missions. "It has improved somewhat," Lt. Gen. Thomas Kelly, senior operations officer for the Joint Chiefs of Staff, said Tuesday afternoon in Washington -- late Tuesday night in the gulf region. "Iraq looks pretty clear."

The weather, described by one senior British official as the "one advantage {Iraqi President} Saddam Hussein has had since the war began," also frustrated efforts to calculate the success of allied bombing raids.

One enterprising A-7 Corsair II pilot, attempting to offer at least token assistance to the battle-damage estimate effort, pulled out his 35mm camera and zoom lens, clicking frames of the power plant he had just bombed below.

"If I had been shot at, I would have been ducking and dodging and rocking and rolling and out of there," said Cmdr. John Leenhouts, who flies missions off the aircraft carrier USS John F. Kennedy in the Red Sea. "But it just seemed like a golden opportunity."

U.S. and British pilots say that while they have been experiencing less antiaircraft artillery resistance from Iraqi forces in the last two days, Iraqi gunners have changed some of their tactics by firing higher. Pilots said that in some regions, the Iraqis also are sending more surface-to-air missiles whizzing toward their planes.

"I look out the window and watch them launch," said a 38-year-old Annapolis man who pilots A-6 Intruder attack planes. "I just sit there and wait and see where it goes. If you panic, you're probably going to get shot down."

The Kennedy now has pulled back from its operating area to assess its five days of steady bombing against Iraq, which was capped by a predawn attack directed at a chemical munitions factory north of Baghdad and a 37-plane assault on a gas-turbine electricity generating plant and other targets in central Iraq, officials on the carrier said.

The ship's planes have been flying so many missions that the flight deck is worn "down to bare metal in places," according to the vessel's aircraft handling officer.

Navy ships on the other side of the Arabian Peninsula today attacked and destroyed an Iraqi mine-laying ship in the northern Persian Gulf, according to military officials.

The foul weather could draw out the air campaign longer than expected in order to allow bombers and attack jets to pound Iraqi troops and hardware in preparation for what field commanders now describe as "G-Day," the likely onset of the ground war.

Today, Army commanders conducted strategy meetings for the beginning of the ground campaign -- which officials said could start in two to four weeks -- while Marine and Navy leaders met aboard the command ship USS Blue Ridge to coordinate plans for a possible Marine amphibious assault on the eastern shores of Kuwait, military officials said.

In eastern Kuwait, Iraqi troops reportedly set two Kuwaiti oil refineries and oil field equipment ablaze in what could be an effort to obscure the surrounding area with smoke by day and temporarily blind pilots using light-sensitive goggles during night operations.

The extent of the damage and resulting fires at the Wafra oil field, which is heavily blanketed with Iraqi troops massed near Kuwait's border with Saudi Arabia, was not known. U.S. military spokesmen here acknowledged the fires but declined to give specifics about the damage.

The oil field damage raised fears that Saddam has begun to make good on his threat to turn Kuwait into "a graveyard" if his country came under attack by the U.S.-led multinational coalition.

The Iraqi military, which has deployed 545,000 troops in a broad swath from southern Iraq and throughout Kuwait to the Saudi border, is dug in behind layers of concertina wire, trenches and minefields. Pilots describe the Iraqi posture as purely defensive and say they have seen no evidence that Iraqi forces intend to abandon their fortifications.

U.S. Marines and the Iraqis have tested each other frequently in the last few days, with the Iraqis lobbing artillery shells and missiles into Marine positions, and the Marines responding by sending helicopters and A-10s to attack the Iraqi missile and artillery emplacements. Today the border activity had dwindled to the sounds of scattered gunfire from Iraqi positions across the border, Marine officials said.

Col. Ron Richard of the Marine 2nd Division said military intelligence has detected "increased movement" on the Iraqi side "back and forth from the border" in the southernmost sections of Kuwait, an indication that the Iraqis are fortifying their positions with infantry, artillery or both.

"Discounting enemy ability is just wishful thinking," Richard told news media combat pool correspondents in a briefing. Iraq "still has a lot of firepower and a lot of willingness to use it."

In a defiant gesture to intensive allied air efforts to eradicate Iraq's Scud missile arsenal, enemy forces sent several more missiles streaking into Tel Aviv and toward the Saudi cities of Riyadh and Dhahran throughout the day. The attacks on Saudi Arabia are believed to come mostly from mobile launchers behind Iraqi border fortifications.

"There's fixed Scuds, mobile Scuds, Scuds hidden in wheeled vehicles, driven anywhere," said A-10 pilot Maj. Scott Hill, 38, of Chagrin Falls, Ohio. "They can be hidden in buildings or disguised as a railroad car. {Iraq has} so many of these damn things, it's like destroying an anthill by stepping on it."

Finding a Scud launcher is easiest, pilots say, when a launch is detected and an A-10 or other aircraft is already in the air and can be dispatched immediately to the launch area. The A-10 pilots say they have destroyed several launchers that way.

The procedure has been made much more difficult by the bad weather, he added, because the best way to track down and destroy a Scud launcher is for a pilot to spot one himself and attack it.

Because of the weather, the A-10s, until now, have not really tested the Iraqi defenses, particularly the bunkers and trenches where they keep their tanks and troops. But with clear weather, the A-10 pilots say, they will soon know how much work remains.

"We're doing things smart," said A-10 pilot David Wappner, 30, of Springfield, Ohio. "We're taking out targets in order." As soon as the air defenses are worn down, "we're going after their infantry, and they have no idea what's going to happen to them," he added. "We're going to hammer them hard."

Nevertheless, commanders are attempting to brace their troops for the brutality of the war that could lie ahead.

"I've told my guys very clearly: Don't think this is going to be a cakewalk, where we walk into the country and they're going to throw their hands up and surrender because we've bombarded them into the stone age," said Lt. Col. Bill Reese, commander of the 1st Calvary Squadron of OH-58 scout helicopters assigned to the Army's 1st Armored Division.

Correspondent Caryle Murphy contributed to this report from Riyadh.