Daily sales of new light vehicles in the U.S. are expected to rise 17.5% in June, compared with year-ago, according to a WardsAuto forecast, but slowing fleet deliveries and flat retail demand likely will keep the seasonally adjusted annual rate lagging behind the first five months.

The WardsAuto outlook calls for auto makers to sell 1.28 million cars and light trucks over 27 selling days this month, for a daily sales rate of 47,406 units, compared with last June’s 40,344 (26 days).

The forecast rate represents a 7.3% decline from May’s 51,158 DSR (26 selling days), a slightly larger month-to-month drop than the average May-to-June change in recent years.

May LV deliveries fell 6.2% below WardsAuto expectations, equating to a 13.7 million-unit SAAR, far less than the prior-month’s 14.4 million.

May’s unexpected downturn came in part as some auto makers’ fleet sales slowed, a trend that may broaden this month as pent-up demand caused by 2011 inventory shortages now largely has been met. Retail demand may be settling down as well, at least for the summer.

The overall economic outlook has darkened somewhat in recent few months. This is reflected by the Conference Board Consumer Confidence Index, which dropped in April and slipped again in May as consumers’ generally gloomy outlook, particularly toward the labor market, grew from month to month.

At least part of that was borne out with the May jobless rate rising slightly from April to 8.2%.

There’s a chance that some of the U.S. economic slowdown is in a lull before another wave of growth, perhaps as early as August, as car buyers anticipate the imminent introduction of ’13 models, including a new generation of some of the most popular midsize vehicles.

The industry’s impressive year-over-year growth so far this year – forecast June sales equate to a 14 million-unit SAAR compared with 11.5 million in 2011 – is measured against the prior-year’s sales rate that was held strongly in check by drastically reduced inventories due to the earthquake and tsunami that hit Japan in March.

The WardsAuto forecast calls for the Detroit Threeto account for 45.9% of June’s forecast LV deliveries. General Motors is expected to lead all auto makers with an 18.8% market share on volume sales of 240,000 units.

Ford easily should hold the No.2 spot with a 16.1% share on 206,000 deliveries, while Chrysler is expected to grab 11.1% of the market with 141,000 units. Combined daily sales for the Detroit Three are forecast to grow 7.7%, compared with year-ago.

Toyota, which has been a larger-than-usual player in fleet sales this year, likely will pull back on deliveries this month, reducing its overall share by a point to 14.3%. The auto maker’s total sales in June are forecast to reach about 182,000 cars and light trucks.

Toyota’s projected 58.7% jump in daily sales reflects year-ago’s supply constraints.

Similarly, Honda’s DSR should climb more than 55%, compared with like-2011, giving Chrysler a bit of run for the No.4 sales spot behind Toyota. However, Honda is forecast to stay in the No.5 position this month, with a strong 10.6% share on 136,000 units.

Hyundai Group is expected to capture more than 9% of June LV sales, with 119,000 deliveries, up 9.7% on a daily basis from year-ago. Nissan, which saw a dramatic falloff in fleet sales last month, likely will remain in the No.7 spot for June, with close to a 7% share on 86,000 units.

Nissan suffered less of an inventory squeeze last year than most other Japanese competitors, and its DSR growth compared with year-ago is expected to fall slightly below the industry’s to 14.7%.

Projected U.S. LV sales in June would bring the year’s first-half total to 7.25 million units, up 14.8% from like-2011.

jsousanis@wardsauto.com