Electric-car company Tesla (TSLA 5.30%) is slated to report its first-quarter vehicle deliveries next week, as the automaker typically provides an update on deliveries and production three days after each quarter ends -- and Tesla's first quarter will come to a close this weekend.

It's fair to say that this is a wildcard quarter for the company. An expected increase in Model 3 production and the company's global expansion during the quarter makes pinpointing a reasonable forecast for vehicle deliveries extremely difficult.

Tesla Model 3 interior

Model 3. Image source: Tesla.

Higher production

Based on what Tesla said in its fourth-quarter shareholder letter about its expectations for production and deliveries in Q1 and the rest of the year, total production for the quarter should be slightly higher than Q4.

"Model 3 production volumes in Fremont should gradually continue to grow throughout 2019 and reach a sustained rate of 7,000 units per week by the end of the year," Tesla said in its fourth-quarter update. While this confirms Tesla's expectation for production to rise, the company was already producing Model 3s at a weekly rate around 5,000 units per week when it entered Q1, so a gradual increase throughout the quarter toward Tesla's year-end target for 7,000 units per week could make a meaningful, though not huge, difference in Tesla's first-quarter deliveries versus Q4's.

With 61,394 Model 3 vehicles produced in Q4, a slightly higher production rate could yield around 67,000 to 71,000 more Model 3 units in Q1.

Meanwhile, given Tesla's expectations for weaker demand for the Model S and X in the first quarter of 2019 because of the reduction of the federal electric-vehicle tax credit on the first of the year, it's likely that the automaker reduced production of the two vehicles. With 25,161 of Model S and X units combined produced in Q4, first-quarter production for the two vehicles will probably be closer to 20,000 units.

These forecasts translate to a total vehicle production estimate between 87,000 and 91,000 units, higher than Tesla's total vehicle production of 86,555 units in Q4.

Check out the latest earnings call transcript for Tesla.

Lower deliveries

Deliveries, however, will probably be much lower than production, as Tesla said it expected to end the quarter with 10,000 units in transit to customers as the company expands overseas. That compares with 2,907 vehicles in transit to customers at the end of Q4.

Subtracting 10,000 from a production forecast of 87,000 to 91,000 units equals an estimate for 77,000 to 81,000 vehicle deliveries. As it turns out, analysts may be using a similar logic for their own estimates; the consensus estimate for Tesla's total vehicle deliveries in Q1 is about 78,000 units, down from about 91,000 units in the fourth quarter of 2018. 

It's worth noting that whether Tesla grows its vehicle deliveries sequentially or not, the company is still growing its business at a staggering rate on a year-over-year basis. Tesla delivered less than 30,000 vehicles in the first-quarter of 2018. 

Look for an update from Tesla on its first-quarter deliveries sometime between April 1 and April 3.