Personal income rose 0.2 percent in February, a tenth above expectations, and spending was up 0.1 percent. But revisions to January's spending data wiped out earlier solid gains and showed spending marginally higher — at 0.1 percent from an earlier 0.5 percent.
Fourth-quarter GDP growth was reported at 1.4 percent Friday, revised up from 1 percent.
Economists had been hopeful the first quarter would show a snapback with growth above 2 percent, and some have been optimistic that weak manufacturing was beginning to show signs of bottoming.
They note the size of the revision to consumer spending is rare.
Read MoreFourth-quarter GDP revised
"It's not falling off the cliff. We're not in a recession but it's consistent with worry," said Swonk.
The February trade gap widened by about a half-billion dollars to — $62.9 billion with both exports and imports higher than expected.
Swonk said she is now forecasting an annualized growth rate for the first quarter of 1 percent or slightly under, from 1.3 percent.
The closely watched Atlanta Federal Reserve's GDPNow forecast model Monday showed a steep drop to a 0.6 percent annualized pace from last week's forecast of 1.4 percent.
The median tracking forecast has fallen by about 1 percent in the past week, a surprising rate of change. But there is other data this week that could positively impact it, such as Friday's March jobs report.
"These GDP (numbers) make no sense. We can count jobs, and job growth is not at all consistent with measured GDP growth," said Mark Zandi, chief economist at Moody's Analytics, in a note.