When the weather is particularly nice in Buenos Aires, they say it is "Peronist weather." Whenever the late president would appear in public, the legend goes, storm clouds would magically vanish in a blaze of sunshine.

Even those who are convinced that Juan Domingo Peron came close to ruining Argentina -- and they are many -- say it is true. Call it charisma, machismo or simple demagoguery, for nearly 20 years, both in office and in exile, Peron had the power to move the people.

It is precisely this power that Argentina's current government -- a military junta composed of the heads of the army, navy and air force, with army commander Gen. Jorge Rafael Videla as president -- does not have. One of the most serious domestic problems now facing the junta is the fact that most Argentines find it, to say the least, uninspiring.

"The biggest problem this government has," said one official within the now emasculated labor movement that once formed the Peronist backbone, "is that there is no enthusiasm for it." Out of fear, "nobody is going to criticize it too strongly. But nobody is going to say anything good about it, either."

It is perhaps axiomatic that military governments are not loved. This particular junta, however, which a year ago ousted Peron's widow, Isabel, at a time when most Argentines agreed that the country was on the road to ruin, started out with a fair amount of good will.

That support has now faded into a sort of dull acceptance of the government's strongarm power to impose its wishes, and an overriding feeling among labor, academicians and politicians that the country has no real direction. "It's true," one high navy official shrugged, "we have no plan, no big program."

What makes Argentina's military government different from that in Chile and other countries where military rule is more obviously institutionalized, is its refusal to be branded as other than a "transition" government. It is determined to maintain a facade of freedom inside a system of both subtle and blatant repression.

It is conventional wisdom here, however, that the government is divided, not only within the junta itself, but into a maze of subgroups that formulate and carry out their own orders. These groups are vaguely labelled "hard-liners," "moderates," a category into which Videla is usually placed, and the "soft-liners."

The only thing that has united them recently, and even managed to unite a good portion of the populace, was anger at President Carter's cutoff of military credits because of alleged human-rights violations.

The benefits of having many factions are that unpopular actions can be passed off as the work of extremists.

The Montoneros and the People's Revolutionary Army, or other groups of leftist guerrillas who are generally credited with acts of terrorism, have by nearly all reckonings been completely annihilated. The nightly, seemingly random, bombing attacks in Buenos Aires in recent weeks are considered the crazed actions of cornered desperados.

But the retaliatory paramilitary kidnapings, secret detentions, tortures and deaths that have become a personal terror and an international humiliation to many Argentines continue unabated. Amnesty International says there are at least 5,000 uncharged political prisoners here. Others put the figure as high as 20,000.

Gen. Albano Harguindeguy, the interior minister, who is considered a "hard-liner," has said at various times that there are no more prisoners than half the number of fingers on one hand, that there have never been any prisoners, and that there may have been some but are no more now. Videla says there are no political prisoners, only detained "subversive delinquents."

During recent weeks a number of prominent civilians have disappeared --his people have no knowledge of them, are believed to be the work of "hard-liners" displeased with "moderate" concessions.

Earlier this month Edgardo Sajon, a director of La Opinion, a leading Buenos Aires daily and press secretary under former President Alejandro Lanusse, disappeared on his way to work. After a personal appeal to Videla. Lanusse said the president assured him that neither federal nor provincial police had any clue to Sajon's whereabouts.

A few days later the bullet-ridden body of Hector Ferreiros, a prominent local journalist who had been abducted from his home by uniformed men, was found by the side of a suburban road.

"You can't call it anarchy," said one socialist politician. "It's not even a dictatorship. It's more like a bunch of little dictatorships."

In mid-March, according to diplomatic sources, a group of American travel agents on a government-sponsored tour were stopped by soldiers as their bus left Buenos Aires' international airport. Made to stand spread-eagled agains the bus, they were frisked their luggage was inspected and they were forced to stand on the side of the road while an officer gave them a 30-minute lecture on the fallacy of President Carter's human rights policy.

Junta spokesman acknowledged that incidents may have occurred, but said they had no knowledge of them.

"This is how they convince the world that Argentina is a safe place where human rights are respected," said one Western diplomat grimly. "Not only does the left hand not know what the right is doing, the left forefinger usually hasn't a clue what the left thumb has in mind."

One thing all factions initially agreed upon was giving a year-long free hand to Economy Minister Jose Alfredo Martinez de Hoz. The results of his free-market policies have been, in many respects, impressive.The only civilian member of the Cabinet, he managed to borrow $1.2 billion, and to pay off $800 million in debts. He also bolstered the national treasury, estimated by one junta spokesman to have reached a rockbottom $10 million at the time of the coup.

For the man on the street, however, the policy has not been so successful. Wage increases averaging around 20 per cent were not nearly enough to offset inflation that, while greatly decreased from neary 800 per cent in 1975, is still at the triple-digit level.

As one local news magazine headlined last week" "Who responsible for inflation now?"

At times, it seems the economy minister himself does not know. Last month, he announced a 120-day freeze on prices including gasoline. A week later, gasoline prices doubled and a week after that, taxi fares doubled.

Part of the problem, as nearly everyone freely admits, regardless of political persuasion, is that "Argentines are selfish people."

"Things are not the same here as in places like Peru or Bolivia," said a leader of the Radical Party that, in freer political times, was the loyal opposition. In largely middle-class Argentina, he said, "the problem is not getting enough to eat, it is getting a new car next year," an infinitely more volatile issue.

The political parties and the labor unions, meanwhile, seek an opening for political dialogue with the junta. At present, parties are officially "suspended" and unions, permitted only on a local level, are run by the military.

It had been widely hoped that Videla's March 31 speech, on the anniversary of the coup would describe such an opening. "Everybody," the Radical leader said, "is waiting to see what happens."

What happened was a call for "national unity" that left the political future, in the words of the political commentator "as muddy as ever."

While calling the junta "the best government available" to Argentina under current circumstances a columnist for the English-language Buenos Aires Herald noted dryly that the situation was, all in all, "distressing."

It is likely to get worse before the sun comes out.