The drivers hinted at the dangers 24 hours earlier and yesterday vivid proof was provided; so vivid it evoked a breathtaking collision here three years ago.
Michael Schumacher's practice session for tomorrow's Belgian Grand Prix here was curtailed when he emerged from the spray and ran into the back of Pedro de la Rosa's Jaguar, a mirror image of the Ferrari driver's collision with David Coulthard's McLaren-Mercedes in the 1998 race.
Then, as yesterday, the German was travelling at a considerably faster pace than the car in front. Then he returned to the pits on three wheels and in a rage, confronted Coulthard. Yesterday he drove back to base with his broken wing lodged under the car. De la Rosa lost the rubber from his rear left wheel.
Both drivers were unhurt but the incident served as a salutary warning of the perils in the rain, which is a regular visitor here.
A characteristic cloudburst sent drivers scurrying for cover early in the afternoon stint. When the rain eased they ventured out again, but inevitably several cars spun off.
De la Rosa had just left the pits and was coasting down the hill towards Eau Rouge when Schumacher came up behind him. The German realised too late that a car was immediately ahead and clipped the rear of the Jaguar as he turned to his left.
The Spaniard said: "I was coming out of the pits and moved to the right when I realised the Ferrari was behind me. I left him the whole road to choose from and he preferred to hit me. I had nowhere to go.
"No one is to blame because there was a lot of spray. It was a racing incident, a typical wet weather accident.''
Schumacher, having won the drivers' championship already, was calm and philosophical, yet suggested he felt De la Rosa was driving too slowly.
He said: "The situation was the usual one when you are running in spray. You have no chance to judge the distance or see the real light. You have to hope that the driver in front behaves normally and accelerates down the straight. I was being careful, not going flat out.
"I just had a feeling he might be going slowly, which is why at the last moment I moved over even though I could not see anything. By then it was already too late.''
Coulthard, whose own practice session ended after three dry laps when he crashed into a barrier, seemed mildly amused that Schumacher had not reacted so aggressively on this occasion.
The McLaren driver said: "This is a timely reminder of how dangerous this circuit can be in the rain.
"People said we were pussycats when we started the race behind the safety car in the rain last year, but this is what can happen here. It doesn't take bravery to drive into a wall of spray, it takes stupidity.
"If it is raining again at the start of the race this time then we should start behind the safety car again. You've just got to be sensible.
"I don't have a problem driving in the wet – I won the one wet race we've had this year. But here the conditions can change from one part of the circuit to another.''
Coulthard, heading the chase for second place in the championship, lost control of the McLaren when he went wide at a corner at 140mph. The car then veered across the circuit and into the Armco. Mechanics worked feverishly to complete repairs before the end of the session, but ran out of time.
Schumacher, still fastest overall despite his accident is, curiously, seeking his first pole position on this, the circuit where he made his Formula One debut a decade ago.
He will, however, be even more intent on marking the occasion by registering a record 52nd Grand Prix victory.
He has promised he will help his team-mate, Rubens Barrichello in his quest to finish second in the championship, but may be hoping the Brazilian is not close enough to hand him the win. There are three more races after this, time enough, he will doubtless be thinking, to make the grand gesture.
BELGIAN F1 GRAND PRIX PRACTICE TIMES (Spa-Francorchamps): 1 M Schumacher (Ger) Ferrari 1min 48.655sec; 2 J Trulli (It) Jordan 1:49.404; 3 R Barrichello (Br) Ferrari 1:49.456; 4 G Fisichella (It) Benetton 1:50.192; 5 M Hakkinen (Fin) McLaren 1:50.239; 6 K Raikkonen (Fin) Sauber 1:51.645; 7 R Schumacher (Ger) Williams 1:50.801; 8 E Irvine (GB) Jaguar 1:51.555; 9 J Alesi (Fr) Jordan 1:51.631; 10 J Button (GB) Benetton 1:51.673; 11 O Panis (Fr) BAR 1:52.071; 12 H-H Frentzen (Ger) Prost 1:52.073; 13 P de la Rosa (Sp) Jaguar 1:52.119; 14 N Heidfeld (Ger) Sauber 1:52.436; 15 J Villeneuve (Can) BAR 1:52.804; 16 J Pablo Montoya (Col) Williams 1:52.829; 17 J Verstappen (Neth) Arrows 1:52.955; 18 F Alonso (Sp) Minardi 1:55.021; 19 T Marques (Br) Minardi 1:55.099; 20 E Bernoldi (Br) Arrows 1:55.491; 21 L Burti (Br) Prost 2:11.037; 22 D Coulthard (GB) McLaren 12:37.913.Reuse content